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Zones humidesMovement ecology of post-breeding gulls reveals wetland connectivity in northwestern Africa
de Víctor Martín-Vélez, Haytem Bouchri, Anis Guelmami, Ursula Hofle, Joan Navarro, María J. Navarro-Ramos, Andy J. Green
In Global Ecology and Conservation, 71 (November, 2026), e04454
En ligne : www.sciencedirect.com[...]
Wetlands are among the most threatened ecosystems worldwide, and their loss increasingly compromises landscape connectivity essential for persistence of waterbird populations. In the Mediterranean region, and particularly in northwestern Africa, conservation prioritisation has largely focused on sites supporting high bird numbers, while the role of wetlands in maintaining functional connectivity remains poorly understood. Here, we quantify wetland connectivity in Morocco using the black-headed gull (Chroicocephalus ridibundus) as a model migratory waterbird. We obtained high-resolution GPS tracking for 64 individuals breeding in south-western Iberia. We combined the tracks of the 19 individuals that moved to Morocco with network analyses, to identify key sites and habitat types that contribute to spatial connectivity. Tracked gulls relied on a heterogeneous network of 26 wetlands, including rivers, dams, lagoons and temporary wetlands. They also used anthropogenic habitats such as landfills and wastewater treatment plants. Network analyses revealed a sparsely connected but spatially structured system, with connectivity concentrated in three main geographical regions. Several unprotected wetlands, particularly rivers and reservoirs, showed high betweenness values revealing their importance for maintaining network integrity, comparable to those of existing Ramsar sites. Removal simulations highlighted the vulnerability of connectivity to the loss of a small number of key sites (nodes) in the wetland network. Furthermore, GPS data show that Moroccan wetlands are more important for black-headed gulls from July to September than expected from eBird data. Our results demonstrate how incorporating movement-based connectivity metrics can improve wetland conservation planning. Protecting functionally important wetlands is critical to safeguard waterbird connectivity, and hence ecosystem resilience, in northwestern Africa.
de Miguel Cabrera-Brufau, Camille Minaudo, Katrin Attermeyer, Alba Camacho-Santamans, Rafael Carballeira, Benjamin Misteli, Jorge Montes-Pérez, Daniel Morant, Biel Obrador, Antonio Picazo, et al.
In Ecological Engineering, 232 (November, 2026), 108080
En ligne : www.sciencedirect.com[...]
Coastal wetlands play a substantial role in regulating Earth's climate through exchanges of greenhouse gases (GHGs). Current European policies promote widespread coastal wetland restoration to reverse historical losses and ongoing pressures. However, substantial uncertainty remains regarding how carbon dioxide (CO2) and methane (CH4) fluxes respond to restoration across different coastal wetland types and whether these responses translate into net climate mitigation in terms of CO2 equivalents (CO2-eq). We measured simultaneous CO2 and CH4 fluxes using static chambers across four seasons at multiple locations spanning preserved, altered and restored sites within six European coastal wetlands of different ecological types. By comparing GHG exchanges and resulting CO2-eq balances across wetlands, we identified dominant biogeochemical drivers of CO2 and CH4 dynamics and assessed the climate mitigation potential of conservation and restoration actions. CO2 fluxes were primarily controlled by landscape-scale vegetation cover and inundation, whereas CH4 emissions responded to less evident changes in water quality, salinity and wetland hydrodynamics. Comparisons of CO2-eq balances between altered and restored sites showed that seagrass replantation was associated with significant mitigation potential under both 100-year and 20-year CH4 warming scenarios, while eutrophication reversal through improved water treatment was only significant under the 20-year scenario. In contrast, other restoration measures modified CO2 and CH4 fluxes in opposing directions, resulting in no significant net change in combined CO2-eq balances. Overall, our results demonstrate that climatic responses to coastal wetland restoration are both GHG-specific and wetland-type dependent, underscoring the need for tailored restoration strategies and robust, multi-GHG monitoring to detect and accurately quantify potential climatic benefits.
de Haytem Bouchri, Rhimou El Hamoumi, Raphaël Musseau, Arnaud Béchet, Jocelyn Champagnon
In Animal Conservation, (en ligne) (July, 2026), 1-11
En ligne : onlinelibrary.wiley.com[...]
Robust estimates of animal population size are critical for effective conservation planning, yet such studies remain scarce in the North African region, making it difficult to assess the population status of various species. Here, we present the results of a national-scale survey of the rare and elusive Marbled duck (Marmaronetta angustirostris) conducted over 2 years in Morocco. Using a two-stage random sampling design, we surveyed 187 secondary sampling units of 0.25 km2 nested within 35 primary sampling units of 100 km2, spanning from the Moulouya River to the Saharan wadis. We applied hierarchical binomial N-mixture models to estimate the breeding population size of the species and identify key breeding habitat features. At the scale of sampled sites that cover 46.75 km2 of wetlands, our best-supported model estimated a total of 24 broods, with an average detection probability of 0.71 (95% BCI: 0.49–0.86), highlighting the need to account for imperfect detection in field surveys. When extrapolated to all Moroccan wetlands (748 km2), this translated into a national breeding population size estimate of 386 broods (95% BCI: 283–487). Emergent vegetation was found to be the strongest predictor of brood abundance. Among wetland types, ponds showed positive associations with brood abundance relative to dams, while rivers were associated with lower abundance. These findings represent the first robust national-scale estimate of Marbled duck breeding population size in Morocco. The analysis highlights emergent vegetation and wetland types as predictors of brood abundance, offering direction for habitat-focused conservation efforts. The scalable survey and modeling framework used here can be adapted elsewhere to improve monitoring and conservation efforts of vulnerable waterbird species.
de Pierre Defos du Rau, Ugoline Godeau, Nicolas Carenton, Jaime Dias, Abakar Saleh Wachoum, BERTRAND Trolliet, Khalil Baddour, Abdramane Chaibo, Guillaume P. Morin, Bruno Portier, et al.
In Proceedings of the National Academy of Sciences, 123(27) (July, 2026), e2603538123
En ligne : www.pnas.org[...]
Lake Chad is both one of the largest transboundary wetlands in Africa and a major biodiversity hotspot. As such, Lake Chad would require sound and long-term biodiversity monitoring, but it is also a war zone. Using several mitigation measures, we succeeded in surveying a major part of it in 2022 to estimate the abundance of wildlife. This study marked the first comprehensive population estimates for some species. Compared to previous total count approaches, we introduced an aerial distance sampling methodology to improve survey safety, repeatability, estimate uncertainty, and reduce detection bias. Due to strong security concerns, a portion of the lake was inaccessible. To overcome this limitation and estimate temporal trends, density surface modeling was applied to estimate species abundance over the entire lake. Locations of conflict events emerged as sites of higher densities for several species, suggesting a “refuge effect,” a rare positive outcome of conflict zones on wildlife. Indeed, we also noted the persistence of endangered large mammal populations, possibly due to reduced anthropogenic pressure from displaced communities. Results indicated that Lake Chad hosts approximately 2.48 million waterbirds, to our knowledge the most important known wetland bird concentration in Africa. Updated population estimates revealed that some species may have experienced positive trends. However, a few species, including transcontinental ones, showed signs of reduced abundance. The study urges actions to protect this ecosystem of major importance for global biodiversity, recommending the establishment of a protected area and World Heritage status for Lake Chad.
de Abdessadeq Boudjaj, Laïla Rhazi, Said Moukrim, Saida Ourraisse, Abdelmjid Zouahri, Mohammed El Madihi, Mouhssine Rhazi, Said Lahssini, Mohamed Ben Bammou, Imane Wahby, et al.
In Hydrobiologia, (en ligne) (April, 2026)
En ligne : doi.org[...]
The role of temporary ponds in carbon budgets remains poorly understood, particularly in arid regions. This study quantified soil organic carbon (SOC) stocks in 15 temporary ponds in Morocco, across three land use types (agricultural, reserve, forest). In each pond, one soil core was collected in each of the three topographic zone (peripheral, intermediate, and central) and divided in three soil depth (0–15, 15–30, 30–45 cm) with sub-samples (3) averaged by layer. Relationship with vegetation abundance and plant diversity (aquatic and terrestrial), hydrological and soil properties were also assessed. SOC content was measured, and factorial ANOVAs with Tukey’s tests were used for statistical analysis. SOC density was significantly higher in agricultural and reserve ponds than in forest ponds. Total SOC stock was positively correlated with hydrology, soil nutrients, and vegetation attributes, while topographic zone, soil depth, or their interaction showed no significant effects. Extrapolation to all 672 ponds in the 2760 km2 study area estimated a total SOC stock of 153,878 metric tons. These results highlight the importance of conserving agricultural ponds and creating new reserves in pond-rich forest areas to maximize carbon sequestration in semi-arid regions.
de Ali Gholamhosseini, Mahta Jafari, Arnaud Béchet
In Ornithology Research, 34(1) (April, 2026), 20
En ligne : doi.org[...]
In recent years, many wetlands in the semi-arid and arid regions of southwest Asia, particularly in southern Iran, have completely dried up, raising significant concerns regarding the reproductive success of the greater flamingos (Phoenicopterus roseus). This study investigates the breeding success of the species in the saline wetlands of Bakhtegan and Maharloo in southern Iran over the breeding seasons 2023 and 2024. In 2023, egg laying initiated around mid-March in Bakhtegan, but the breeding site was subsequently deserted around April 23 during the egg hatching period likely due to drought conditions and disturbances from humans and predators. We counted a total of 1,953 nests and 538 dead chicks. The extremely low precipitation (about 33 mm) during the wet seasons of 2024 further resulted in suboptimal breeding conditions, leading to the absence of flamingos in Bakhtegan. Survey in Maharloo demonstrated breeding success in 2023, with an estimated 1,700 to 2,200 chicks. However, subsequent surveys in 2024 revealed no nests or chicks. Droughts, coupled with human interventions such as upstream dam construction and agricultural irrigation, have severely threatened flamingo populations, contributing to flamingo breeding failures and increased chick mortality.Thirteen personal letters to a wetland
de C Max Finlayson, Columba Martínez-Espinosa, Swapan Paul, R Eugene Turner, Pierre Horwitz, Leonardo Maltchik, Gillian Davies, Andy Herb, John Conallin, Ritesh Kumar, et al.
In Wetland Science & Practice, 44 (April, 2026), 96-110
Thirteen letters to a wetland have been prepared by individuals and combined in a single article. The letters express the personal feelings and views of the writers (or epistolists) to a wetland of their choice, including regret about their condition or the pressures the wetland had experienced, as well as respect and appreciation for their values. The letters are provided as a way of sharing these views with others and in doing so encouraging them to also express their own views in the intimate format of a letter. The letters are writtend to wetlands in seven countries and serve as a model for others in different countries.
de Mauro Fois, Carles Burguera, Necmi Aksoy, Gianluigi Bacchetta, Simonetta Bagella, Giulio Barone, Ioannis Bazos, Imtinen Ben Haj Jilani, Leanne Camilleri, Miquel Capó, et al.
In Biological Conservation, 313 (January, 2026), 111595
En ligne : www.sciencedirect.com[...]
Mediterranean wetlands are highly sensitive ecosystems, particularly vulnerable to human pressure and shifts in precipitation and temperature regimes. Wetland plants can be particularly threatened in Mediterranean insular contexts, where such habitats are naturally smaller and more fragmented than in their continental counterparts. This study investigated 275 species of vascular wetland plants that were considered to be at least regionally threatened across 2217 islands and islets in the Mediterranean. We provided both global and local IUCN conservation assessments (summarized in a ‘conservation concern’ index) and ‘assessment completion’ (i.e. knowledge level) for each taxon as well as a geographic distribution among islands, wetland types, and life forms. Most of wetland plants were threatened at the regional level, although assessment completion was generally low, except for endemics. Inland and endemic wetland plants were more threatened than the rest. A phylogenetic signal was detected, highlighting that Orchidaceae and Apiaceae were of particularly high conservation concern, while other families, especially Amaranthaceae, exhibited low levels of assessment completion. No geographical patterns were found in terms of conservation concern and assessment completion. Our findings provide critical insights into biodiversity patterns, identify conservation gaps and priorities and contribute to the development of targeted strategies for the protection of wetland plants, which are crucial indicators of the entire natural capital of Mediterranean island ecosystems.Long-Time Dynamics in a North African Coastal Ramsar Site, the Sidi Boughaba Lake
de Said Moukrim, Jihane Tellal, Said Lahssini, Abdessadeq Boudjaj, Mouhssine Rhazi, Mohammed El Madihi, Mohamed Ben Bammou, Mustapha Moukrim, Er-riyahi Saber, Imane Wahby, et al.
In Ekológia (Bratislava), 44(2) (Decembre, 2025), 147-159
En ligne : www.sciendo.com[...]
Coastal wetlands host a large part of the world’s biodiversity and provide various ecosystem services with a known economic value. However, they experience many pressures due to anthropogenic and natural drivers, causing periodic changes in their structure and functioning. Earth Observation provides opportunities for monitoring water surface dynamics and understanding the impacts of different drivers on wetland degradation. This study had two objectives: to assess the spatiotemporal dynamic of the Sidi Boughaba Lake surface area (Mediterranean and North African coastal Ramsar site, Morocco) over 38 years (1984–2021) and to identify natural and anthropogenic drivers of this dynamic, mainly land-use and land-cover changes and policies. This work focused on the use of multiple datasets based on remote sensing images within a cloud-based computing platform. Time series of satellite images were classified and used after a series of processing procedures to assess the land use and land cover and water extent dynamics. Results reveal that over 38 years, the lake shows intra- and inter-annual variations, including significant losses of permanent water impacting its dynamic and extent. Those trends call into question the urban and agricultural policies adopted. Pressure on resources and the regressive trend recorded in the dynamic of the lake are likely to increase further in future years if effective protection measures are not implemented. The results of this study help authorities, civil society, and decision makers to make decisions and call for action to protect these areas and maintain their capacity to provide ecosystem services and address global concerns such as biodiversity conservation and climate change mitigation.High prevalence and diversity of alphacoronaviruses in bats in Southern France
de Océane Rieu, Anaïs Dufau, Jordan Meliani, Lionel Brazier, Marion Vittecoq, Carole Leray, Anthony Olivier, Emmanuel Cosson, Frederic Thomas, Eric Leroy, et al.
In EcoHealth, (en ligne) (August, 2025)
En ligne : doi.org[...]
Zoonotic diseases are increasingly affecting global health, making it crucial to understand viral dynamics in wildlife reservoirs like bats. Bats are well-established coronavirus reservoirs, and their proximity to human habitats in France raises concerns about zoonotic transmission. This study investigates the prevalence, diversity, and phylogenetic relationships of coronaviruses in bats from the Camargue and Eastern Provence, two ecologically distinct regions. A total of 785 bat guano samples were collected non-invasively, with 154 (19.6%) testing positive for coronavirus RNA, among the highest infection rates observed in European studies. Camargue samples were entirely from Pipistrellus bats, with a prevalence of 20.1%, while Provence showed greater genus diversity and prevalence ranging from 1.3% to 35.6%. Phylogenetic analysis identified Alphacoronaviruses in four subgenera: Nyctacovirus, Myotacovirus, Decacovirus, and Minunacovirus, alongside unclassified sequences. No coronavirus related to human-infecting strains (e.g., HCoV-229E) was detected. However, the combination of high prevalence, proximity to humans, and potential for host-switching led to the investigation of coronavirus infection in bats, a topic with limited data in France. These findings highlight the ecological role of bats and the importance of continuous viral monitoring, filling a gap in knowledge about coronavirus circulation in European bat populations.Wetlands and dragonflies under threat in the Gediz delta, Türkiye
de Philippe Lambret, Şafak Arslan, Lisa Ernoul, Anthony Olivier, Serdar Özuslu, Çağdaş Yaşar, Özge Yaylalı
In Dragonfly Conservation Europe Newsletter, (en ligne) (August,2025), 12-14
En ligne : www.gbif.org[...]
The Gediz delta covers ca. 400 km², most of which is occupied by agricultural crops (mainly cereals and cotton). Despite the designation of large portions of the delta as protected areas, many pressures continue to threaten the ecologically sensitive zones. Pressures such as urban expansion, water over-abstraction, intensive grazing, spread of invasive plant species, and unsustainable agricultural practices are accentuated by the lack of integrated management and enforcement of policies. In addition, the dominant wind direction and geographical position of the delta contribute to the transport of anthropogenic pollution into the area. Pesticides and fertilizers from surrounding agricultural lands, further degrades the quality of wetlands. Irrigation needs have intensified during the last decades, resulting in illegal damming and an increase in pumping water from the Gediz River. As a result, the freshwater inflows feeding the remaining natural habitats have dramatically decreased, leading to the salinization of many wetlands. This reduction in freshwater input has also led to habitat fragmentation, further isolating temporary wetland patches and negatively affecting species dispersal and ecosystem connectivity. In addition, recent changes in the hydraulic management of some protected areas of the delta have changed some wetlands into pasturelands. Although grazing pressure in the delta has not been quantified, field observations indicate that livestock —particularly cattle and sheep— enter the ponds and disturb the vegetation along the banks. This practice is likely to have negative impacts on dragonfly larvae, especially with the reduction of plant shoots that the larvae need for metamorphosis. Given that dragonflies are often used as bioindicators, their decline may reflect broader ecosystem degradation throughout the delta.
de Leonie Jonas, Jon E. Brommer, Martin Jung, Michal Balaz, John J. Borg, Luka Bozic, Preben Clausen, Antoine Derouaux, Koen Devos, Cristian Domşa, et al.
In Biological Conservation, 308 (August, 2025), 111213
En ligne : www.sciencedirect.com[...]
Biodiversity is increasingly negatively affected by climate warming, making this issue a major conservation concern. Many bird species respond to warming temperatures by shifting distribution ranges, but these shifts often lag behind temperature changes. Protected areas (PAs) can facilitate such shifts, but a growing body of literature suggests that not all PAs facilitate climate warming responses equally, as realized management actions can differ. Here, we study waterbird community change as a response to climate warming in relation to targets of conservation projects implemented in Natura 2000 protected areas across the EU. We combine long-term waterbird survey data (i.e. International Waterbird Census) with data on conservation funded by the EU LIFE program, the main EU instrument for conservation. We used the community temperature index to measure thermal community changes over 28 years. We found community adjustment to climate warming lagged behind temperature. However, community change was twice as fast in sites were conservation was targeting wetland habitats compared with sites without habitat conservation. Targeting waterbirds directly did not lead to variation in community change compared with other types of species conservation. Our results imply that on the management level conservation targeting a community's habitat (rather than targeting the species group directly) is more likely to provide benefits for community adjustment to climate warming. This study demonstrates that management actions currently not targeting climate warming impacts on biodiversity, have the potential to support species responding to climate warming. However, conservation strategies need to be adapted to the challenges arising with climate warming.
de Dilara Arslan, Elie Gaget, Kerim Cicek, Anthony Olivier, Thomas Galewski, Ömer Döndüren, Anis Guelmami, Lisa Ernoul, Arnaud Béchet
In BMC Ecology and Evolution, 25(1) (June, 2025), 58
En ligne : doi.org[...]
Wetlands have been some of the most destroyed ecosystems over the last century, with important land-use changes resulting from agricultural, industrial, and urban development. Gediz Delta is a large wetland on the Aegean coast of Western Türkiye with natural areas affected by conversion to agriculture and urban developments from the Izmir metropolis. We assessed the effects of landscape type (natural, agricultural, and urban) on the composition of breeding bird (90 species) and reptile (14 species) communities in the Gediz Delta between 2019 and 2021. We used generalized linear models to estimate the effect of landscape types on community indexes and joint species distribution models to assess how species-specific habitat preferences explained their responses to landscape type.Status of Lestes macrostigma in Bulgaria
de Philippe Lambret, Stanimira Deleva, Spas Uzunov, Dimitar Popov
In Odonatologica, 54(1/2) (2025), 53-84
Measuring population trends of freshwater insects helps to assess their conservation status and to design management protocols for wetlands. Lestes macrostigma is restricted to temporary brackish waters, a limited and fragmented habitat. Throughout its range this species is threatened at different levels, and, in Bulgaria, it has been assessed as “Critically Endangered”. In the past, along the Black Sea coast, it was known to be abundant and reproducing at two sites: Shablenska Tuzla Lake and Poda Protected Area. At a third site, Pomorie Lake, only a few individuals were recorded without clear evidence of reproduction. We aimed at updating its distribution along the Bulgarian Black Sea coast and determining the conservation status of its populations by conducting surveys from 2021 to 2024 at 53 localities, mainly within coastal lagoons and estuaries. We recorded all Odonata species along with their various life stages and reproductive behaviour. Other resident species recorded in association with L. macrostigma were Lestes barbarus, L. dryas, Ischnura elegans, Aeshna affinis, Sympetrum fonscolombii, S. meridionale, and S. striolatum. We counted L. macrostigma adults along walks and extrapolated abundance over the entire sites and season. Lestes macrostigma population size reached hundreds of thousands of adults at Shablenska tuzla and Pomorie Lake. At Nanevska tuzla and Atanasovsko Lake, two new sites for the species, thousands of adults were present. However, we found that L. macrostigma had disappeared from at least a part of Poda Protected Area, most likely because of a change in water management practices. As the timing of the flooding period is a key feature of the species’ habitat, we found that its presence in the temperate Bulgarian estuaries was unlikely. As conservation management plans are still lacking for Shablenska tuzla and Pomorie Lake, the future of the two largest L. macrostigma populations of Bulgaria of international importance seems tenuous and uncertain. Therefore, key actions for the conservation of L. macrostigma are the proper management of its existing reproductive sites and restoring or recreating temporary wetlands.Monitoring coastal dynamics after working with nature practices in the Rhone delta
de Morgane Jolivet, Cecile Puigserver, Olivier Boutron, Francois Sabatier, Samuel Meulé, Philippe Larroude, Loic Willm, Emilie Luna-Laurent
In Coastal Engineering Proceedings, 38 (June, 2025), 50
En ligne : icce-ojs-tamu.tdl.org[...]
The site of the “Étangs et Marais des Salins de Camargue” (EMSC) is located southern France in the Rhône Delta, facing Mediterranean sea, at the heart of the Camargue Regional Natural Park. This site, formerly dedicated to salt production, is now owned by the Coastal Conservatory and co-managed by the Camargue Regional Natural Park, Tour du Valat, and the French National Society for the Protection of Nature. A habitat restoration project was initiated in 2011 and continues as part of the development of a 2023-2032 management plan and the site's participation in the European H2020 Rest-Coast project. This restoration aims to facilitate the recolonization of the area by plant (seagrass, salt marsh) and animal species, reestablishing the natural hydrological processes of the site. An adaptive coastal management strategy is also applied on this site, with the decision to no longer maintain the historical dikes of the salt production site facing the sea, leading to their gradual collapsing. Protection against the risk of marine submersion is ensured by an landward seawall, which will be elevated, as part of the coastal strategy defined for the greater Rhône Delta. Natural hydro-morphodynamic processes are reestablishing locally, creating new connections with the sea and the formation of beach and barrier areas through overwash. This results in the emergence of a natural buffer zone that will better address the consequences of climate change or storms, such as marine submersion and salinization.Le marais d'Orx, au confluent de l'histoire et des défis contemporains
de Hervé Cubizolle, Yohann Montane
In Courrier de la Nature (Le), 345 (Mai, 2025), 6 - 11
Le marais d'Orx, dans les Landes, est une vaste zone humide de 1000 hectares, transformée en Réserve Naturelle Nationale en 1995. Ce site, autrefois un chenal de l'Adour, est un hotspot de biodiversité, particulièrement pour les oiseaux. Il joue un rôle crucial dans la conservation des habitats humides et la gestion des crues. Des efforts de restauration visent à améliorer la biodiversité et la gestion écologique, tout en luttant contre les espèces invasives et en sensibilisant les visiteurs.
de Florian Altermatt, Gregor Klaus
In Ornis, 2/25 (April, 2025), 7-11
En ligne : www.ornis.ch[...]
Biodiversité bleu-vert. L'eau et les zones rurales sont souvent considérées séparément dans la conservation de la nature. Cependant, les liens entre l'eau et la terre s'étendent bien au-delà du rivage et des zones inondables: les insectes ailes, par exemple, sont une source très importante de nourriture pour les oiseaux, tandis que, à l'inverse, les feuilles servent de nourriture pour les amphipodes. La conservation de la nature devrait donc tenir davantage compte des nombreuses interactions entre l'eau et les habitats terrestres à l'avenir.Characterizing governance models for upscaling wetland restoration
de Arnaud Terrisse, Michael Karner, Julia Kaufmann, Lisa Ernoul
In Environmental Management, (en ligne) (March, 2025)
En ligne : doi.org[...]
Governance is a key element for effective conservation, sustainable management and restoration of ecosystems. Improving governance is essential for upscaling restoration actions around the world. Governance systems were studied in eleven on-going European wetland restoration sites using a two-step process. First, an in-depth examination of seven sites from six countries was made using key informant interviews. This information provided the basis for developing four governance models (Monocentric, Polycentric, Community-based and Networking). Most of the sites presented a dominant governance model, but also incorporated some dimensions of the other models to a lesser degree. The models were tested and evaluated in an additional seven sites in five countries. The analysis revealed that the governance models were highly subject to the geographical features, land ownership structures and different histories of the sites. Strengths, weaknesses, and supporting and limiting factors were associated with each model. This research shows how governance models are adapted to site specific conditions and how these adaptations can be used to enhance governance processes in existing sites, upscale restoration efforts or set the groundwork in new restoration sites.
de Ömral Ünsal Özkoç, Cem Akın, Anthony Olivier, Dilara Arslan
In Herpetology Notes, 18 (2025), 839-843
En ligne : figshare.com[...]
This study aims to present new data on the relationships between domestic water buffaloes and reptiles.Species abundance and richness patterns of wintering waterbirds in sétif wetlands complex (algeria)
de Hadjer Gouga, Ettayib Bensaci, Zouhir Boulgueraguer
In Transylvanian Review of Systematical and Ecological Research, 27(1) (2025), 67-80
Surveys of wintering waterbirds were conducted in 17 wetland areas along the wetland complex of the Sétif region, with the aim to determine the variability of waterbird populations and the ornithological value of these wetlands for further strengthening of their management and conservation. Our survey revealed a total species richness of 47 waterbird species. The total regional population averages 31921 individuals per year recorded from 2014 to 2021. Among these species, 12 are dominant representing 94%. Based on the calculated occurrence index for each species, the population consists of two common species, 10 frequent species, and 35 rare species. The Kruskal-Wallis test (also referred to as one-way ANOVA) was utilized to compare the distribution of data series related to species richness, average abundance, and values of Shannon diversity and evenness among the different studied sites, showing highly significant differences between the wetlands.
de Taylor B. Craft, Theunis Piersma, Jos C. E. W. Hooijmeijer, Bing-Run Zhu, Malaika D'Souza, Eoghan O'Reilly, Rienk W. Fokkema, Marie Stessens, Heinrich Belting, Christopher Marlow, et al.
In Journal of Applied Ecology, (en ligne) (November, 2024)
En ligne : onlinelibrary.wiley.com[...]
Knowledge of the habitat requirements for migratory species throughout their full annual cycle is necessary for comprehensive species protection plans. By describing seasonal shifts of space-use patterns in a key nonbreeding area, the Senegal Delta (Mauritania, Senegal), this study addresses a significant knowledge gap in the annual cycle of the rapidly declining continental Black-tailed Godwit Limosa limosa limosa. We fitted continuous-time stochastic-process movement models with GPS location data to describe the core areas used by 22 GPS-tagged godwits over the 2022–2023 nonbreeding period. We mapped key habitat types, such as floodplain wetlands and rice fields, via supervised classification of satellite imagery. Godwits in the Senegal Delta show a distinct shift in habitat use over the nonbreeding period. The core areas of godwits in the early stages of the nonbreeding period (the wet season) were primarily in natural wetlands and fields with newly planted rice. As the rice crop matured and became too dense, godwits moved towards more recently sown rice fields. Later, as floodwaters receded and rice fields dried out, godwits abandoned rice fields and shifted towards natural wetlands with fewer invasive plants, particularly within the marshes and shallow floodplains of nature-protected areas in the lower Delta. Synthesis and applications: Our findings illustrate the shifting importance of natural and agricultural wetlands for godwits at different stages of the nonbreeding season. Protected areas in the Senegal Delta, particularly the Djoudj National Bird Sanctuary (Senegal) and Diawling National Park (Mauritania), are crucial habitats during the dry season as godwits prepare for their northward migration, whilst rice fields take a key role during the wet season. Conservation efforts should prioritize eradicating invasive plants from the Djoudj and Diawling, as well as promote agroecological management in specific rice production complexes indicated in this study.
de Maite Martínez-Eixarch, Pere Masqué, Anna Lafratta, Paul Lavery, Samuel Hilaire, Lluís Jornet, Cyrille Thomas, Arnaud Boisnard, Néstor Pérez-Méndez, Carles Alcaraz, et al.
In Science of The Total Environment, 950 (November, 2024), 175224
En ligne : www.sciencedirect.com[...]
Coastal wetlands are crucial in climate change regulation due to their capacity to act as either sinks or sources of carbon, resulting from the balance between greenhouse gas (GHG) emissions, mainly methane (CH4), and soil carbon sequestration. Despite the paramount role of wetlands in climate regulation few studies investigate both aspects. The Camargue is one of the largest wetlands in Europe, yet the ways in which environmental and anthropic factors drive carbon dynamics remain poorly studied. We examined GHG emissions and soil organic carbon (SOC) stocks and accumulation rates in twelve representative wetlands, including two rice fields, to gain insights into the carbon dynamics and how it is influenced by hydrology and salinity. Mean CH4 rates ranged between – 87.0 and 131.0 mg m−2 h−1and the main drivers were water conductivity and redox, water table depth and soil temperature. High emission rates were restricted to freshwater conditions during summer flooding periods whereas they were low in wetlands subjected to summer drought and water conductivity higher than 10 mS cm−1. Nitrous oxide emissions were low, ranging from – 0.5 to 0.9 mg N2O m−2 h−1. The SOC stocks in the upper meter ranged from 17 to 90 Mg OC ha−1. Our research highlights the critical role of low-saline wetlands in carbon budgeting which potentially are large sources of CH4 but also contain the largest SOC stocks in the Camargue. Natural hydroperiods, involving summer drought, can maintain them as carbon sinks, but altered hydrology can transform them into sources. Artificial freshwater supply during summer leads to substantial CH4 emissions, offsetting their SOC accumulation rates. In conclusion, we advocate for readjusting the altered hydrology in marshes and for the search of management compromises to ensure the compatibility of economic and leisure activities with the preservation of the inherent climate-regulating capacity of coastal wetlands.
de Elie Gaget, O. Ovaskainen, U. Bradter, F. Haas, L. Jonas, A. Johnston, T. Langendoen, A. S. Lehikoinen, T. Pärt, D. Pavón-Jordán, et al.
In Animal Conservation, (en ligne) (November, 2024)
En ligne : onlinelibrary.wiley.com[...]
Climate warming is driving changes in species distribution, but habitat characteristics can interact with warming temperatures to affect populations in unexpected ways. We investigated wintering waterbird responses to climate warming depending on habitat characteristics, with a focus on the northern boundary of their non-breeding distributions where winter climatic conditions are more extreme. At these Nordic latitudes, climate warming is expected to drive positive changes in species occurrence and abundance, with likely differences in species-specific responses. We analyzed the occurrence and abundance of 18 species of waterbirds monitored over 2,982 surveys at 245 inland wetlands over a 25-year period in Sweden. We used hierarchical modeling of species communities (HMSC) which enabled us to relate species-specific changes to both functional traits and phylogenetic relatedness. We investigated occurrence and abundance changes in response to average temperature, temperature anomalies, site area, site protection status (Natura 2000), and land use in agricultural and urban surfaces. Unsurprisingly, both average temperatures and temperature anomalies were the most important variables influencing positively waterbird occurrence and abundance. For 60% of the species, the effect of temperature anomalies was even stronger in large or protected wetlands. Geese and mallard occurred more often at sites surrounded by agricultural and urban surfaces, respectively, but their occurrence in these habitats was not affected by interactive effects with climate warming. Species abundance was greater inside protected areas only for 11% of the species, but occurrence probability was higher inside protected areas for 44% of the species. Overall, we observed that species thermal affinity was a strong predictor for positive species response to temperature anomalies, and that species sharing similar phylogenetic history had similar relationships with environmental variables. Protection of large wetlands and restoration of the surrounding habitats are two targets for climate change adaptation strategies to facilitate future responses of waterbirds to climate warming.Water Birds Adaptation and Monitoring in an Artificial Wetland in Northern Algeria
de Kamal Hachour
In Pakistan Journal of Zoology, (en ligne) (November, 2024)
En ligne : researcherslinks.com[...]
We have, for the first time, provided data on the adaptation of water birds in an artificial wetland (Taksebt Dam, northern Algeria) based on a 4-years (2018-2021) study. A total of 17 species of water birds belonging to ten families and seven orders have been recorded. The number of water birds that frequented the study area varied from 1025 to 1396 individuals. The Anseriformes (Anatidae) were recorded as the most dominant, represented by five species: Mallard Anas platyrhynchos, Northern shoveler Spatula clypeata, Common shelduck Tadorna tadorna, Eurasian wigeon Mareca penelope and Eurasian teal A. crecca. The species that have adapted and became resident at the Taksebt Dam include: Mallard A. platyrhynchos, Common moorhen Gallinula chloropus and Great crested grebe Podiceps cristatus. The other species use the dam for feeding and/or resting.
de PAVEL Pinchuk, Włodzimierz Meissner
In Journal of Ornithology, 165(4) (October, 2024), 935-945
En ligne : doi.org[...]
We analysed primary and secondary feather moult and fat reserves in 539 Common Snipes captured in the middle Pripyat River Valley, an important stopover site for waders in Central Europe, between 2002 and 2022. The average daily rate of feather growth was 1.89% in primaries and 2.27% in secondaries, being one of the highest documented in waders. The estimated duration of growth for a single flight feather varied from 11 to 21 days in primaries and from 8 to 11 days in secondaries. Moreover, multiple flight feathers (up to 14) were replaced simultaneously. As a result, the wing moult in Common Snipes was rapid with the mean primary moult duration estimated at 53 days (28 June–20 August) according to the Underhill–Zucchini model, and only 20 days in secondaries (31 July–20 August) based on moult estimates of individual secondaries. Hence, although secondary feathers began to grow when primary moult was already advanced, moulting of both flight feather groups was completed in most birds at almost the same time. Our study shows that Common Snipe in the middle Pripyat River Valley exhibit very rapid wing moult with large wing gaps. Fat reserves and thus body mass of Common Snipes were the lowest when the wing gap was greatest, compensating for their reduced wing area. Late and slow movement towards wintering grounds, allows them to moult rapidly at the early stage of autumn migration, which is likely to occur only in sites with abundant food resources.
de Maurice Benmergui, Marine Galy, Thomas Blanchon, Jocelyn Champagnon, Lok Tamar, Stefano Volponi
In Alauda, 92(3) (Septembre, 2024), 203-224
La Spatule blanche se reproduit depuis 2006 dans Ia Dombes, région composée de plus de 1 300 étangs piscicoles extensifs situés à quelques dizaines de kilomètres de l’agglomération lyonnaise. Sa population est l’une des plus petites et des plus fragiles de France, car soumise a l’aléa d’un système particulier d’exploitation des étangs, d’assèchement (a assec ii) et de drainage estival, qui semble compromettre Ia stabilité des colonies. La Dombes est historiquement Ia première et reste l’une des régions les plus continentales où se reproduit Ia Spatule blanche en France : le littoral le plus proche est celui de Ia Méditerranée, avec Ia Camargue, située à environ 300 km au Sud. Depuis 1991, cette espèce est baguée dans le cadre de plusieurs programmes européens de conservation. Plusieurs de ces oiseaux bagués fréquentent Ia Dombes. A partir des observations réalisées d’après 53 individus, entre 1991 et 2020, nous tentons de remonter aux origines géographiques des individus présents en Dombes. Les résultats révèlent, que les oiseaux contrôlés et bagués au nid proviennent de Camargue (67,9 %), des Pays-Bas (11,3 %), d’Italie (9,4 %), de Croatie (3,8 %), d’Allemagne (3,8 %) et de Belgique (1,9 %). Hormis Ia France, 13 pays accueillent des spatules en escale : l’Espagne (28,3 %); les Pays-Bas (20,8 %); l’Allemagne (9,4 %); l’Italie, Ia Belgique et la Mauritanie (7,5 % chacun); le Maroc (5,7 %); le Portugal et la Tunisie (3,8 % chacun); Ia Suisse, l’Autriche, le Sénégal et l’Algérie (1,9 % chacun). Les étapes migratoires correspondent globalement à celles des oiseaux camarguais qui empruntent Ia route côtière pour rejoindre I ’Espagne, le Maroc et le Banc d’Arguin mauritanien pour y hiverner. L’âge de première visite des Spatules en Dombes est dominé par Ia classe des oiseaux de 3-4 ans (39,6 %), puis celle des 5-6 ans (24,5 %). La durée minimale de séjour postnuptial est de 33 jours mais reste variable et 26 % des spatules restent plus de deux mois. Bien que marginales par rapport au nombre élevé d’oiseaux bagués en Europe du Nord, en Camargue, en Italie ou en Croatie, les contrôles réalisés dans Ia Dombes démontrent de possibles échanges entre : ces populations. Celle de Ia Dombes apparait, comme celle de Camargue, comme une population d’origine mixte, issue du groupe Mer du Nord-Atlantique d’une part et, du groupe Méditerranée Centrale d’autre part (Champagnon et al., 2019). Les oiseaux italiens et croates quant à eux appartiennent au groupe de Ia Méditerranée centrale, mais leur présence dans Ia Dombes, fortuite, témoigne d’une certaine fidélité à Ia région tant en migration qu’en période de reproduction. A ce jour, seuls deux oiseaux d’origine camarguaise sont nicheurs dans les colonies de Ia Dombes confirmant l’influence de Ia population camarguaise sur celle reproductrice de Ia Dombes. Un autre événement original est Ia dispersion postnuptiale d’une fraction des oiseaux camarguais vers les étangs de Ia Dombes et qui peut atteindre ponctuellement 200 à 300 individus. Nous discutons l’intérêt pour Ia Dombes de rejoindre les régions et pays réunis sur Ia question de Ia conservation de l’espèce dans un contexte climatique pouvant fragiliser notamment certaines populations littorales, ainsi que d’affirmer l’importance écologique et régionale de Ia biodiversité d’une région qui vient d’être désignée parmi les 18 zones humides emblématiques de France dans le nouveau Plan d’Action Zones Humides 2022-2026.
de Foued Hamza, Abdulhakim M. Abdi, Mohamed-Ali Chokri, Lamia Yacoubi, Habib Dlensi, Naoufel Hammouda, Abdenaceur Ghlis, Badreddine Jemaa, Marwa Elghoul, Ahlem Hedhili, et al.
In Landscape Ecology, 39(8) (August, 2024), 151
En ligne : doi.org[...]
The intensification and expansion of human activities have caused profound changes in global wetlands and their associated aquatic bird communities. Understanding the mechanisms that drive the spatial assemblages of wetland birds is important for the development of effective conservation and management strategies.Exposure of wetlands important for nonbreeding waterbirds to sea-level rise in the Mediterranean
de Fabien Verniest, Thomas Galewski, Olivier Boutron, Laura Dami, Pierre Defos du Rau, Anis Guelmami, Romain Julliard, Nadège Popoff, Marie Suet, Loic Willm, et al.
In Conservation Biology, 2024 (May, 2024), e14288
En ligne : onlinelibrary.wiley.com[...]
Sea-level rise (SLR) is expected to cause major changes to coastal wetlands, which are among the world's most vulnerable ecosystems and are critical for nonbreeding waterbirds. Because strategies for adaptation to SLR, such as nature-based solutions and designation of protected areas, can locally reduce the negative effects of coastal flooding under SLR on coastal wetlands, it is crucial to prioritize adaptation efforts, especially for wetlands of international importance for biodiversity. We assessed the exposure of coastal wetlands important for nonbreeding waterbirds to projected SLR along the Mediterranean coasts of 8 countries by modeling future coastal flooding under 7 scenarios of SLR by 2100 (from 44- to 161-cm rise) with a static inundation approach. Exposure to coastal flooding under future SLR was assessed for 938 Mediterranean coastal sites (≤30 km from the coastline) where 145 species of nonbreeding birds were monitored as part of the International Waterbird Census and for which the monitoring area was delineated by a polygon (64.3% of the coastal sites monitored in the Mediterranean region). Thirty-four percent of sites were threatened by future SLR, even under the most optimistic scenarios. Protected study sites and study sites of international importance for waterbirds were, respectively, 1.5 and 2 times more exposed to SLR than the other sites under the most optimistic scenario. Accordingly, we advocate for the development of a prioritization scheme to be applied to these wetlands for the implementation of strategies for adaptation to SLR to anticipate the effects of coastal flooding. Our study provides major guidance for conservation planning under global change in several countries of the Mediterranean region.
de Laura Fablet, Anouk Pellerin, Diane Zarzoso-Lacoste, Vincent Dubut, Laurence Walch
In Knowledge and Management of Aquatic Ecosystems, 425 (2024), 1-20
En ligne : www.kmae-journal.org[...]
Environmental and/or climate changes, occurring at a global or local scale, can significantly impact the diets, health, and population dynamics of waterbirds. This study aimed to develop an effective tool, using DNA metabarcoding of fecal samples, for monitoring waterbird diets during the breeding season in a Ramsar freshwater wetland in Northern France. We collected bird feces across eight marshes with varying anthropic usage. The majority of samples (69%) were from five waterbird species: Eurasian coot (Fulica atra), Eurasian moorhen (Gallinula chloropus), mallard (Anas platyrhynchos), mute swan (Cygnus olor), and grey heron (Ardea cinerea). DNA was extracted from 116 samples, with plant and invertebrate primers used to undertake multi-marker metabarcoding. Despite a negative impact of uric acid on DNA amplification, we observed significant dietary variations among bird species and sampling sites. Wetland bird diets primarily consisted of four arthropod families, dominated by Chironomidae and Asellidae. The number of plant families detected was higher, consisting of 33 families, with Poaceae highly prevalent within wetland bird diets. This study shows that using DNA metabarcoding to explore interactions between waterbirds and trophic resources is a promising approach to assist wetland management and assess the effect of environmental changes.
de Till Jonas Linke
In Ornis, 2/24 (April, 2024), 14-17
Le marais de la vallée fluviale le long de la Peene, au nord-est de l'Allemagne, compte parmi les derniers paysages alluviaux d'Europe proches de l'état naturel, avec de vastes tourbières basses. La restauration complète des polders de drainage autrefois utilisés de manière intensive a permis de développer à nouveau des habitats précieux pour des oiseaux rares et d'autres espèces.
de Hugo Rafael Soares Ferreira, Jocelyn Champagnon, José A. Alves, Tamar Lok
In Oecologia, February (February, 2024)
En ligne : doi.org[...]
When wintering at different sites, individuals from the same breeding population can experience different conditions, with costs and benefits that may have implications throughout their lifetime. Using a dataset from a longitudinal study on Eurasian Spoonbills from southern France, we explored whether survival rate varied among individuals using different wintering sites. In the last 13 years, more than 3000 spoonbills have been ringed as chicks in Camargue. These birds winter in five main regions that vary in both migratory flyway (East Atlantic vs. Central European) and migration distance (long-distance vs. short-distance vs. resident). We applied Cormack–Jolly–Seber models and found evidence for apparent survival to correlate with migration distance, but not with flyway. During the interval between the first winter sighting and the next breeding period, long-distance migrants had the lowest survival, independently of the flyway taken. Additionally, as they age, spoonbills seem to better cope with migratory challenges and wintering conditions as no differences in apparent survival among wintering strategies were detected during subsequent years. As dispersal to other breeding colonies was rarely observed, the lower apparent survival during this period is likely to be partly driven by lower true survival. This supports the potential role of crossing of natural barriers and degradation of wintering sites in causing higher mortality rates as recorded for a variety of long-distance migrants. Our work confirms variation in demographic parameters across winter distribution ranges and reinforces the importance of longitudinal studies to better understand the complex demographics of migratory species.Mapping the way to wetland conservation: A geomatic approach for the Oran region
de Berrichi Faouzi, Chamakhi Djemoui, Benshila Naima
In Wetlands, 44(3) (February, 2024), 31
En ligne : doi.org[...]
Wetlands, like any other ecosystem, have important characteristics (hydrology, soil, vegetation) that distinguish them from other ecosystems and allow them to provide vital habitats for insects, fish, birds, and other wildlife. Wetlands in the Wilaya of Oran, Algeria, include the Great Sebkha, the marshes of Macta, Lake Telamine, and the salt pans of Arzew, all known for their rich diversity of fauna and flora, are known worldwide for their ecological importance. The objective of this work is to develop an operational geomatic approach for the delineation, evaluation and use of information on North African wetlands. The Digital Atlas made it possible to highlight another aspect of this significant diversity of wetlands in western Algeria, through a new technique for presenting the results used in a web mapping. In the context of global changes driving a steep erosion of biodiversity, this study shows the importance of wetlands in western Algeria and allows citizens to learn about the richness, beauty and extent of their natural heritage. It contributes to public awareness and provides a valuable assessment and evaluation tool available to decision makers and professionals in the field of nature management and conservation. The findings of this study demonstrate, among other things, that considerable scientific advances of a practical kind may be made in the field of remote sensing. These can potentially be linked to managers' needs for tools to inventory and delineate wetlands and to monitor wetland development and conservation status. The Digital Atlas made it possible to discover another aspect of the consequent diversity of North African wetlands, through a new technique of presenting results in the context of web mapping.
de Andy J. Green, Carolina Guardiola-Albert, Miguel Ángel Bravo-Utrera, Javier Bustamante, Antonio Camacho, Carlos Camacho, Eva Contreras-Arribas, José L. Espinar, Teresa Gil-Gil, Ivan Gomez-Mestre, et al.
In Wetlands, 44(2) (January, 2024), 20
En ligne : doi.org[...]
Acreman et al. (Wetlands 42:63, 2022) reviewed evidence for ecological damage to the Doñana wetlands (UNESCO World Heritage Site [WHS] and Ramsar site), Spain, associated with intensification of groundwater use, particularly for agriculture. Acreman et al. presented a multistep methodology for evidence-based risk assessment that involves identification of conservation issues, and a systematic review of scientific evidence for ecological damage and its causes. However, they involved few local scientists, used a questionable methodology in stakeholder selection and involvement, used a flawed conceptual framework, and an incomplete literature review. We propose improvements to their methodology. They overlooked or misinterpreted key evidence, and underestimated the impacts that abstraction for irrigation for red fruits (mainly strawberries), rice and other crops has had on Doñana and its biodiversity. They reported groundwater level depletion of up to 10 m in the deep aquifer, but wrongly concluded that there is no evidence for impacts on the natural marsh ecosystem, the dune ponds or the ecotone. Groundwater drawdowns are actually up to 20 m, and have inverted the formerly ascending vertical hydraulic gradient in discharge areas. Phreatic levels have been lowered from 0.5 to 2 m in some areas. Groundwater abstraction has caused multiple ecological impacts to temporary ponds and marshes in the WHS, as well as to terrestrial vegetation, and should be urgently reduced. Furthermore, Acreman et al. focused on groundwater quantity while overlooking the importance of severe impacts on quality of both surface and groundwater, intimately connected to the use of agrochemicals for irrigated crops.
de Imene Benzina, Abdelkrim Si Bachir, Abdelkrim Arar, Anis Guelmami, Christian Perennou
In Present environment and sustainable development, 18(1) (2024)
En ligne : www.pesd.ro[...]
Wetlands are present within intricate ecological settings, exhibiting dynamic changes over time and across different areas with regard to their functional and structural diversity. Several approaches have been introduced for ecosystem analysis and management since 1990s, where Driver – Pressure – State – Impact – Response (DPSIR) framework is one of the widely used approaches for assessing and managing environmental problems. In this study, we proposed a DPSIR framework as a model in the Sebkhates of Aures wetland complex (SAWC, Northeast of Algeria), in order to create a regional wetland observatory to deliver ecosystem services within current state of changes resulted from socioeconomic drivers. DPSIR facilitates the identification of essential indicators to detect threats to the Sebkahtes of Aures wetlands complex (SAWC), influencing policymakers to enhance the protection and management of these wetlands. In line with the established DPSIR framework. This same approach and methodology could be applied to the other 15 wetlands complexes known in Algeria, culminating in the creation of a national wetland observatory. Furthermore, DPSIR can be employed as an analytical tool for policy making in the context of sustainable management of wetland ecosystems and can serve as a model in the establishment and development of various observatory programs in Algeria.
de Anis Guelmami
In Euro-Mediterranean Journal for Environmental Integration, December (December, 2023)
En ligne : link.springer.com[...]
Les zones humides méditerranéennes sont les écosystèmes les plus riches et les plus productifs de la région et sont essentielles pour l'adaptation au changement climatique et l'atténuation de ses effets. Cependant, malgré leur importance, elles ont subi une destruction importante au fil du temps. On estime qu’environ la moitié des zones humides naturelles ont disparu depuis les années 1970, et la tendance régionale ne montre aucun signe de ralentissement. Il est donc urgent de mettre en œuvre des solutions concrètes pour préserver les zones humides restantes et restaurer celles qui ont disparu. La disponibilité croissante de données d'Observation de la Terre (OT) libres et gratuits a permis de cartographier ces écosystèmes et de suivre leur état et leurs tendances. Dans cet article, nous démontrons comment ces outils peuvent aider à la pré-identification des sites candidats pour la restauration des zones humides à grande échelle, à travers la cartographie et la délimitation des habitats humides existants et perdus, leur usage actuel et l'estimation des efforts nécessaires pour recréer ceux ayant été perdus et transformés. L’approche a été testée dans le bassin versant du Sebou, au Maroc, ainsi que celui de la Medjerda, transfrontalier entre l'Algérie et la Tunisie. Les produits cartographiques obtenus ont permis d'identifier une superficie de zones humides perdues potentiellement restaurables de plus de 7000 km² et 1700 km², dans les deux bassins respectivement. Ces résultats présentent une grande valeur pour la gestion des ressources en eau et l'aménagement du territoire car ils peuvent améliorer et aider les efforts de priorisation pour la restauration des zones humides aux échelles locales, nationales et régionale. Ils peuvent servir de données de base pour identifier les sites candidats à la mise en œuvre d'actions de restauration des zones humides en tant que Solutions fondées sur la Nature, régénérer leurs habitats et réhabiliter les services écosystémiques qu'elles fournissent à la société.Evolution of Land Use in the Beni-Belaid Wetland Ramsar Site in North-eastern Algeria
de Salaheddine Roula, Zahira Bouziane
In Genetics & Biodiversity Journal, 7(2) (November, 2023), 28–38
En ligne : journals.univ-tlemcen.dz[...]
This study aims to make a characterization of the different ecosystems by type of land used at the level of the Beni-Belaid wetland located in the North-East of Algeria, which presents an important tool for decision-making, as regards the management and preservation of the area, as well as for the prediction of scenarios of'probable evolution in the future. Three aerial photos (1973, 1988 and 2008) and a Google Earth satellite image (2020) were used. We proceeded to the selection of the study data, cartographic processing (scanning the maps, geo-referencing, assembly and finally the calibration), determination of the different classes of land use, and calculating the areas of the different land occupations using the Arcgis 10.8 software. The results show a fluctuation in the evolution of land use in the Beni-Belaid nature reserve; the surface area of anthropogenic environments (agriculture, dwellings) increased between 1973 and 2020, to the detriment of natural environments (wooded dunes, forests, lakes, etc.), also reveal very significant threats in the short and medium term, which appear mainly to be linked to intensive agro-pastoral practices and the modification of local hydrology by excessive pumping of water from the lakeLa Camargue, un delta face au défi climatique
de Jean Jalbert
In Annales des mines - Responsabilité et environnement., 112 (Octobre 2023), 104-107
En ligne : www.annales.org[...]
Le delta du Rhône, comme tous les deltas du monde, est sur la ligne de front des changements climatiques. À la suite de son endiguement consécutif à des inondations majeures à la fin de XIXe siècle, cette vaste plaine deltaïque a été le siège d’un extraordinaire récit de conquête et de maîtrise : digues, pompes et réseaux hydrauliques ont permis de dompter ce pays rétif, de s’affranchir des principales contraintes – inondations, sel, submersions marines – pour enfin « mettre en valeur » ce territoire, y développer une agriculture productive, sécuriser ses habitants. Pourtant cette période de stabilité touche probablement à son terme. Sous les effets puissants du changement climatique, ce territoire rappelle aux humains que la richesse d’un delta vient précisément de sa dynamique, des flux qui le traversent. Flux d’eau douce et de sédiments, flux d’eau salée, flux biologiques, flux humains... Il nous rappelle sa nature profonde : un territoire mouvant, mobile par essence, siège de l’impermanence des choses. Et si la Camargue était un parfait laboratoire pour inventer un nouveau récit, celui de l’adaptation et de la résilience ?Trente ans après, un nouvel éclairage sur la situation du Râle d’eau Rallus aquaticus en Alsace
de Benoît Wassmer, Alain Willer
In Ciconia, 47(1-2) (Septembre, 2023), 51-75
Il y a 30 ans, l’Alsace fut l’une des rares régions européennes à avoir tenté d’apprécier la situation du Râle d’eau sur l’ensemble de son cycle annuel. Retenu comme espèce cible des « Roselières » dans le cadre du programme Interreg Ramsar Biodiversité 2019-2021 (LPO, NABU, ILN), l’occasion s’offrait de renouveler l’opération. En 2020-21, dans 34 sites des bras morts du Rhin au étangs du Sundgau, 12 observateurs ont consacré plus de 200 heures de terrain, effectué 1 030 stations de repasse (usage de l’enregistrement du cri dit de « porcelet qu’on égorge ») et cartographié 54 territoires avec un duo (TD) et 169 territoires avec un individu (TI) en automne, 23 (TD) et 104 (TI) en hiver, 12 (TD) et 46 (TI) au printemps et 21 (TD) et 68 (TI) en été. Le contexte météorologique est à l’origine de la différence de physionomie inter saisonnière constatée à 30 ans d’intervalle : analogue pour ce qui est du maximum automnal et de la baisse hivernale, certes atténuée, il en fut tout autrement de la période printanière et estivale qui vit en lieu et place d’une baisse modérée (– 29 %) encore accentuée (- 19 %), une forte baisse (- 61 %) et un phénomène de rebond de niveau comparable (+ 52 %). Phragmitaies couchées par les lourdes chutes de neige de la mi-janvier, reprise de la végétation retardée par un printemps froid, et conditions pluvieuses et très fraîches qui ont perduré, ont engendré un report de la nidification en deuxième partie de saison. À cet égard, 2021 constitue une nouvelle illustration de l’opportunisme de l’espèce. Un minimum de 41 territoires de nidification a été obtenu sur 18 sites : en en détenant 78 %, le bilan est en faveur des sites protégés qui ont été renaturés. À la plus forte progression enregistrée en Petite Camargue alsacienne (doublement à minima), le plus fort déclin noté sur le Schafskoepfel (perte de 80 à 90 %) qui accueillait il y a 30 ans, la densité la plus forte d’Alsace (11 à 13 couples sur 2,5 ha). Les dates de ponte, estimées à partir des observations de 64 nichées extraites de la base de données (1978-2021), s’étalent d’avril à début août avec un maximum en mai (n = 28) et lors des deux premières décades de juin (n = 21). En 1991, les sites témoins représentaient près de 60 % de l’effectif nicheur régional. Sur cette base, l’Alsace aurait accueilli 58 à 163 couples en 2021. Lors des meilleures années, le minimum est de 150 couples. Alors que la situation du Râle d’eau est devenue précaire dans les bras morts du Rhin soumis au déclin des roselières et à la pénétration croissante par l’homme et les sangliers, veiller à la pertinence des mesures conservatoires et améliorer la connectivité des dernières zones humides sont une priorité.
de Omar F. Al-Sheikhly, S.B. Mousavi, G.M. Yoxon
In OTTER, 9 (September 2023), 8
En ligne : ottershop.co.uk[...]
de Delphine Ducros, Rodolphe Devillers, Antoine Messager, Marie Suet, Abakar Saleh Wachoum, Clemence Deschamps, Babakar Matar Breme, Ib Krag Petersen, Yves Kayser, Nicolas Vincent‐Martin, et al.
In Journal of Applied Ecology, Online (August, 2023), 13
En ligne : besjournals.onlinelibrary.wiley.com[...]
Human pressure on ecosystems has strongly increased over the last decades and now impacts even the most remote regions. To help mitigate these impacts, it is crucial to designate protected areas in regions that retain a high level of ecological integrity. However, ecological data remain scarce for many such areas, making the systematic design of new protected zones challenging.
Following a request from local managers, we developed an original methodological approach to help design new zoning for a pre-existing protected area in a remote, data-poor Sahelian wetland of southern Chad, a vast area rich in biodiversity and exploited by diverse human activities. The method involved first collecting extensive aerial survey data (6252 records) on birds and mammals and then analysing this through a combination of distance sampling and density surface modelling. The biodiversity data, combined with ecological predictors, helped model species distribution layers that were then incorporated with socio-economic constraints into the systematic conservation planning tool Marxan.
This approach produced an array of protected zoning options that met three levels of conservation objectives set by experts, corresponding to proportions of individuals from given species to protect in the proposed protected area. Frequent exchanges with local managers allowed the analyses to be refined, resulting in seven potential scenarios to be considered for conservation purposes.
Synthesis and applications. In a context of high data scarcity, lack of access and short-term conservation objectives, this combined approach that optimizes newly obtained data via a suite of modelling tools can facilitate identifying and protecting natural areas in regions most in need of urgent conservation policy.Anticiper les changements climatiques pour protéger la biodiversité des zones humides
de Fabien Verniest, Isabelle Le Viol
In The Conversation, 207483 (Juillet, 2023)
En ligne : theconversation.com[...]
Les aires protégées jouent un rôle clé dans la conservation de la biodiversité. Alors que de nombreuses devraient voir le jour d’ici à 2030 suite à l’accord de Kunming-Montréal, il est essentiel de penser leur emplacement afin d’anticiper au mieux les futures menaces pour la biodiversité.
Ainsi, en Méditerranée, de très nombreuses zones humides menacées par d’importants changements futurs de climat et d’usage des terres ne sont toujours pas protégées. Cette situation pourrait compromettre l’adaptation au changement climatique des oiseaux qu’elles abritent.Phenology and spatio-temporal distribution of Ardeidae in Lac Tonga (North-eastern Algeria)
de L. Ouarti, N. Nouri, A. Lazli, K. Missaoui, M. Houhamdi
In Ukrainian Journal of Ecology, 13(1) (July, 2023), 37–49
En ligne : www.ujecology.com[...]
In this study, a 2600-ha Ramsar site, Lac Tonga, in northeastern Algeria, was fortnightly surveillance, for seven months, from December 2021 to June 2022. The aim was to monitor and determine the spatio-temporal distribution of Ardeidae. A total of seven species were inventoried, including the Western Cattle egret Ardea ibis (1701 individuals) and the Little egret Egretta garzetta (265 individuals). The other species were the Squacco heron Ardeola ralloides, Grey heron Ardea cinerea, Purple heron Ardea purpurea, Black-crowned Night heron Nycticorax nycticorax and Great egret Ardea alba, with 69, 56, 54, 51 and 35 individuals respectively. During the study period, maximum abundance was observed during May (A=582 individuals), and species richness generally varied between 3 and 5 species. The highest diversity and equitability indices values were noted during June (H'=1.4 bits and E=0.88), indicating the presence of a balanced population. The monitoring of Ardeidae’ spatial distribution shows that they exploit mainly the western and northeastern parts of the lake with an important occupation during the study period.
de Saida Bougoffa, Imene Benzina, Salah Telailia, Abdelkrim Si Bachir
In Environmental & Socio-economic Studies, 11(2) (June, 2023), 16-28
En ligne : www.sciendo.com[...]
A socio-economic study were carried out in the wetlands complex of Aurès Sebkhates, in North Eastern Algeria. This study aimed to identify the ecosystem services obtained by local stakeholders, describe the anthropogenic impacts and evaluate the vulnerability and threat levels of three Ramsar wetlands: Garaet Timerganine (freshwater), Garaet Annk Djemel & El Merhsel (brackish water) and Sebkhet Ezzmoul (salt water). A socio-economic survey was conducted of 70 randomly selected households (social group) and 24 people belonging to the local administration (focus group). Vulnerability and threat levels were analyzed. Provisioning and monetary value are the most relevant ecosystem services (water pumping, grazing, agriculture, area for recreation, plant and egg collection, salt mining). Indirect ecosystem services rendered by the studied wetlands (water treatment/flood control) are only known by the focus group. 95% of the surveyed locals believed that the studied wetlands have experienced significant degradation in recent years mainly by human activity. Our results revealed significant threats due to salt mining and the excessive water pumping practiced within the three sites. Natural stressors such as drying out, erosion and siltation also contribute to the disturbance of these wetlands.
de Sara Kolbenschlag, Eric Bollinger, Verena Gerstle, Carsten A. Brühl, Martin H. Entling, Ralf Schulz, Mirco Bundschuh
In Science of The Total Environment, 873 (May, 2023), 162351
En ligne : www.sciencedirect.com[...]
Emerging aquatic insects link aquatic and adjacent terrestrial food webs by subsidizing terrestrial predators with high-quality prey. One of the main constituents of aquatic subsidy, the non-biting midges (Chironomidae), showed altered emergence dynamics in response to the mosquito control agent Bacillus thuringiensis var. israelensis (Bti). As riparian spiders depend on aquatic subsidy, they may be affected by such changes in prey availability. Thus, we conducted a field study in twelve floodplain pond mesocosms (FPMs), six were treated with Bti (2.88 × 109 ITU/ha, VectoBac WDG) three times, to investigate if the Bti-induced shift in chironomid emergence dynamics is reflected in their nutritional value and in the diet of riparian spiders. We measured the content of proteins, lipids, glycogen, and carbohydrates in emerged Chironomidae, and determined the stable isotope ratios of female Tetragnatha extensa, a web-building spider living in the riparian vegetation of the FPMs. We analysed the proportion of aquatic prey in spiders' diet, niche size, and trophic position. While the content of nutrients and thus the prey quality was not significantly altered by Bti, effects on the spiders' diet were observed. The trophic position of T. extensa from Bti-treated FPMs was lower compared to the control while the aquatic proportion was only minimally reduced. We assume that spiders fed more on terrestrial prey but also on other aquatic organisms such as Baetidae, whose emergence was unaffected by Bti. In contrast to the partly predaceous Chironomidae, consumption of aquatic and terrestrial primary consumers potentially explains the observed lower trophic position of spiders from Bti-treated FPMs. As prey organisms vary in their quality the suggested dietary shift could transfer previously observed effects of Bti to riparian spiders conceivably affecting their populations. Our results further support that anthropogenic stressors in aquatic ecosystems may translate to terrestrial predators through aquatic subsidy.
de Hana Čížková, Tomáš Kučera, Brigitte Poulin, Jan Kvĕt
In Diversity, 15(5) (May, 2023), 629
En ligne : www.mdpi.com[...]
The common reed (Phragmites australis) is a frequent dominant species in European wetlands. Yet, its performance can vary in response to different combinations of environmental factors. This accounts for P. australis decline on deep-water sites, its stable performance in constructed wetlands with subsurface horizontal flow and its expansion in wet meadows. Reed stands provide habitats for nesting, feeding or roosting of vulnerable bird species. Conservation measures aim at preventing or stopping the decline of P. australis stands, increasing their micro-habitat heterogeneity and reducing the reed penetration into wet meadows. Service-oriented measures aim at providing suitable conditions for direct use of reed stalks for roof thatching or as a renewable energy crop or the use of the reed-dominated habitats for waterfowl hunting, cattle grazing or fishing. The compatibility between nature conservation and different socioeconomic uses can be promoted by collective agreements, agri-environmental contracts or payments for ecosystem services of the reedbeds. In situations with multiple uses, a modelling approach considering the participation of all the stakeholders concerned can be a useful tool for resolving conflicts and developing a shared vision of the respective socio-ecosystem.
de Abdeslam Rihane, Abdelmottalib Nahli, Rhimou El Hamoumi, Mohamed Chlaida
In Ostrich, 94(1) (May, 2023), 48-59
En ligne : www.ajol.info[...]
The reproduction of the Western Marsh Harrier Circus aeruginosus in submerged and dried up thickets of French tamarisk Tamarix gallica at El Maleh Dam reservoir, Benslimane Province, Morocco, was studied through monitoring nests in three successive years (2017-2019). Systematic field investigation showed that the nests were concentrated exclusively in a narrow and shallow area upstream of the dam. The abundance of tamarisk is a determining factor in the breeding success of the Western Marsh Harrier at this site, by supporting the nests and giving them some protection from predation while the birds are close to agricultural fields, a favourable hunting ground. A study of individual broods revealed a relatively small clutch size (3.5 eggs per nest) and that incubation took 32 days on average. Compared with previous reports for this species elsewhere, the chicks fledged relatively early (33 or 35 days), but with a low fledgling success rate not exceeding 33.9%. The low fledgling success is partly attributable to the structure of the habitat, as the dense dry vegetation above the water level limits the movement of chicks out of nests yet favours the drowning of those that fall from the nest. Breeding success is influenced by a reduction in hunting territory caused by drops in the water level during periods of drought, poor climate conditions, and disturbance caused by human activities in the reservoir lake and riparian farmland. In addition to these environmental factors, nest failure due to nest destruction is related to the experience of the pairs in choosing the nesting site and their ability to weave the nest-building materials. Further study is needed on the characteristics of this highly specific habitat and its state of conservation, the reproduction of coexisting bird populations, and human activities around the breeding site.Compositional breakpoints of freshwater plant communities across continents
de Jorge García-Girón, Jani Heino, Lars Baastrup-Spohr, John Clayton, Mary de Winton, Tõnu Feldmann, Camino Fernandez-Alaez, Frauke Ecke, Patrick Grillas, Mark V. Hoyer, et al.
In Limnetica, 42(2) (March, 2023), 1
En ligne : www.limnetica.net[...]
Compositional breakpoints of freshwater plant communities across continents unravelling patterns and mechanisms of biogeographical transitions is crucial if we are to understand compositional gradients at large spatial extents, but no studies have thus far examined breakpoints in community composition of freshwater plants across continents. Using a dataset of almost 500 observations of lake plant community composition from six continents, we examined, for the first time, if such breakpoints in geographical space exist for freshwater plants and how well a suite of ecological factors (including climatic and local environmental variables) can explain transitions in community composition from the subtropics to the poles. Our combination of multivariate regression tree (MRT) analysis and k-means partitioning suggests that the most abrupt breakpoint exists between temperate to boreal regions on the one hand and freshwater plant communities harbouring mainly subtropical or Mediterranean assemblages on the other. The spatially structured variation in current climatic conditions is the most likely candidate for controlling these latitudinal patterns, although one cannot rule out joint effects of eco-evolutionary constraints in the harsher high-latitude environments and post-glacial migration lags after Pleistocene Ice Ages. Overall, our study supports the foundations of global regionalisation for freshwater plants and anticipates further biogeographical research on freshwater plant communities once datasets have been harmonised for conducting large-scale spatial analyses.
In Naturae, 2023(3) (Mars, 2023), 35-45
En ligne : sciencepress.mnhn.fr[...]
Les enjeux de conservation de la biodiversité ainsi que les besoins d’amélioration des connaissances sur les interactions entre grands herbivores et écosystèmes nécessitent la mise en place de dispositifs de suivis standardisés. Dans le contexte du programme de conservation de la Vache Marine landaise et de la gestion des prairies humides à Molinie du plateau landais (région Nouvelle-Aquitaine, France), un dispositif expérimental a été mis en place en 2019 pour le suivi des effets de la Vache Marine landaise dans le cadre de la conservation et la restauration des espaces naturels humides. La conception du dispositif, baptisée « Communauté-Population-Sol » (CPS) est novatrice et intègre trois composantes-clés de l’écosystème : la communauté végétale, la population végétale dominante et le sol, via des relevés exhaustifs de végétation vasculaire, des caractérisations de traits biologiques de la population végétale dominante (Molinia caerulea (L.) Moench) et des paramètres physico-chimiques du sol. Les mesures initiales effectuées dans le dispositif CPS montre une parfaite homogénéité quant aux propriétés initiales des placettes, avant l’effet différentiel de l’exclusion de pâturage. Aucune différence significative de structure de communauté végétale (biodiversité), de caractéristiques de la Molinie (nécromasse, traits foliaires) et de paramètres édaphiques (pH, carbone, nutriments) n’a été mise en évidence entre les modalités d’exclos et de pâturage à l’installation, ce qui garantit une absence de biais initial au niveau des placettes de suivi. Les dispositifs de type CPS ont pour vocation d’être généralisés et adaptés pour permettre une évaluation intégrée des mesures de gestion par le pastoralisme dans les espaces naturels, bien plus fine que les simples suivis de végétation.
de Fabien Verniest, Isabelle Le Viol, Romain Julliard, Laura Dami, Anis Guelmami, Marie Suet, Wed Abdou, Hichem Azafzaf, Nadjiba Bendjedda, Taulant Bino, et al.
In Biological Conservation, 279 (March, 2023), 10
En ligne : www.sciencedirect.com[...]
Thermal adjustment of waterbird communities to climate warming is crucial but hampered by natural habitat conversion, increasing their climatic debt. As it is, in contrast, facilitated in protected areas, assessing the adequacy of the current protected areas network with respect to future climate and land-use changes and identifying priority sites to protect is of major importance. In this study, we assess the thermal adjustment limitations that non-breeding waterbird communities might experience by the end of the 21st century in the Mediterranean region to highlight priorities for wetland protection. Priorities were set by combining the exposure of waterbird communities to natural habitat conversion and climate warming with their thermal specialization. The latter was calculated using winter abundance data of 151 species from 2932 sites of the International Waterbird Census in 21 Mediterranean countries. Exposure was assessed using future projections of temperature and land-use under four CMIP6 scenarios (SSP1–2.6, SSP2–4.5, SSP3–7.0, and SSP5–8.5). We found that strictly protected areas are located in wetlands whose waterbird communities, without protection, would likely experience high limitations in thermal adjustment in the coming decades. This highlights that the location of existing protected areas may effectively support the thermal adjustment of waterbird communities to future climate warming. However, 490 sites considered at risk lack protection, including 32 sites of international importance for waterbirds, stressing the need to strengthen the protected areas network in these sites in priority. Our study provides important guidance for conservation planning in the Mediterranean region to support waterbird responses to climate change. /
Dans notre étude, nous avons évalué les difficultés potentielles des communautés d’oiseaux d’eau hivernants à ajuster leur composition aux futurs changements de température en combinant la spécialisation thermique de la communauté avec deux métriques d’exposition à l’augmentation future des températures hivernales et à la perte future d’habitats naturels à l’horizon 2090 selon quatre scénarios futurs différents. Nous avons ainsi constaté que les aires protégées, et notamment celles strictement protégées, sont situées dans des zones humides dont les communautés d'oiseaux d'eau, sans protection, auraient probablement connu de fortes difficultés d'ajustement thermique au cours des prochaines décennies. Cela met en évidence la pertinence de l'emplacement des aires protégées existantes qui pourront faciliter de manière efficace l'adaptation thermique des communautés d'oiseaux d'eau au réchauffement climatique futur. Cependant, nous avons également identifié 490 sites à risque et ne bénéficiant d'aucun statut de protection, dont 32 sites d'importance internationale pour les oiseaux d'eau, ce qui souligne la nécessité de renforcer le réseau d'aires protégées méditerranéen dans ces sites en priorité.
de Juan G. Navedo, Theunis Piersma
In Conservation Letters, Online (February, 2023), 7
En ligne : onlinelibrary.wiley.com[...]
With its focus on wetlands, the Ramsar Convention provides the clearest global agreement helping the conservation of migratory waterbirds. Two specific criteria (5 and 6) support the scientific basis for sites to achieve Ramsar recognition based on waterbird counts, while criterion 4, on species and ecological communities, also plays a role. Other international conventions and agreements follow these criteria. We identify several reasons why the listing thus established can only “catch” the absolute minimum wetland network for the conservation of migratory waterbirds. We argue that individual tracking and modern observational tools allow to better delineate the areas needed to effectively give migratory waterbird populations full life cycle protection. The sophisticated techniques to measure population characteristics now available should be used to modernize the guidance for the application of Criteria 4 and 6 of the Ramsar Convention for waterbirds, based on (i) time spent in a site throughout migration; (ii) critical (“untouchable”) sites; (iii) robustness of designated site network including buffer areas; (iv) full life cycle information—including early life phases; and (v) refuges used on-and-off during migration in emergency situations. In these enhanced ways, migratory waterbirds can enact their roles as effective sentinels of the ecological state of the world.
de Sébastien Rapinel, Léa Panhelleux, Guillaume Gayet, Rachel Vanacker, Blandine Lemercier, Bertrand Laroche, François Chambaud, Anis Guelmami, Laurence Hubert-Moy
In Heliyon, 9(2) (February, 2023), 17
En ligne : www.cell.com[...]
While wetland ecosystem services are widely recognized, the lack of fine-scale national inventories prevents successful implementation of conservation policies. Wetlands are difficult to map due to their complex fine-grained spatial pattern and fuzzy boundaries. However, the increasing amount of open high-spatial-resolution remote sensing data and accurately georeferenced field data archives, as well as progress in artificial intelligence (AI), provide opportunities for fine-scale national wetland mapping. The objective of this study was to map wetlands over mainland France (ca. 550,000 km2) by applying AI to environmental variables derived from remote sensing and archive field data. A random forest model was calibrated using spatial cross-validation according to the precision-recall area under the curve (PR-AUC) index using ca. 135,000 soil or flora plots from archive databases, as well as 5 m topographical variables derived from an airborne DTM and a geological map. The model was validated using an experimentally designed sampling strategy with ca. 3000 plots collected during a ground survey in 2021 along non-wetland/wetland transects. Map accuracy was then compared to those of nine existing wetland maps with global, European, or national coverage. The model-derived suitability map (PR-AUC 0.76) highlights the gradual boundaries and fine-grained pattern of wetlands. The binary map is significantly more accurate (F1-score 0.75, overall accuracy 0.67) than existing wetland maps. The approach and end-results are of important value for spatial planning and environmental management since the high-resolution suitability and binary maps enable more targeted conservation measures to support biodiversity conservation, water resources maintenance, and carbon storage.
de Hugo Clément, Stephanie Gaucherand, Guillaume Gayet, Florence Baptist, Jérôme Porteret, Pierre Caessteker, Claire Magand, Anne Vivier
In Sciences Eaux & Territoires, 42 (January, 2023), 31-34
En ligne : revue-set.fr[...]
A large number of wetland restoration/creation operations are emerging in France. The efficiency of these operations must be evaluated in the short, medium and long term. It is also the case of compensation operations which, in order to demonstrate the efficiency of their restoration/creation operations, must have robust and easily mobilisable indicators. The HYDRINDIC indicator was thus developed to assess the efficiency of wetland restoration/creation operations from a hydrological point of view.that are now under an obligation to achieve results and must, in order to demonstrate the efficiency of their restoration/creation operations, have robust and easily mobilisable indicators. The HYDRINDIC indicator was thus developed to assess the efficiency of wetland restoration/creation operations from a hydrological point of view.Extensive global wetland loss over the past three centuries
de Etienne Fluet-Chouinard, Benjamin D. Stocker, Zhen Zhang, Avni Malhotra, Joe R. Melton, Benjamin Poulter, Jed O. Kaplan, Kees Klein Goldewijk, Stefan Siebert, Tatiana Minayeva, et al.
In Nature, 614(7947) (February, 2023), 281-286
En ligne : www.nature.com[...]
Wetlands have long been drained for human use, thereby strongly affecting greenhouse gas fluxes, flood control, nutrient cycling and biodiversity1,2. Nevertheless, the global extent of natural wetland loss remains remarkably uncertain3. Here, we reconstruct the spatial distribution and timing of wetland loss through conversion to seven human land uses between 1700 and 2020, by combining national and subnational records of drainage and conversion with land-use maps and simulated wetland extents. We estimate that 3.4 million km2 (confidence interval 2.9–3.8) of inland wetlands have been lost since 1700, primarily for conversion to croplands. This net loss of 21% (confidence interval 16–23%) of global wetland area is lower than that suggested previously by extrapolations of data disproportionately from high-loss regions. Wetland loss has been concentrated in Europe, the United States and China, and rapidly expanded during the mid-twentieth century. Our reconstruction elucidates the timing and land-use drivers of global wetland losses, providing an improved historical baseline to guide assessment of wetland loss impact on Earth system processes, conservation planning to protect remaining wetlands and prioritization of sites for wetland restoration4.Wetland emission and atmospheric sink changes explain methane growth in 2020
de Shushi Peng, Xin Lin, Rona L. Thompson, Yi Xi, Gang Liu, Didier Hauglustaine, Xin Lan, Benjamin Poulter, Michel Ramonet, Marielle Saunois, et al.
In Nature, 612(7940) (December, 2022), 477-482
En ligne : www.nature.com[...]
Atmospheric methane growth reached an exceptionally high rate of 15.1 ± 0.4 parts per billion per year in 2020 despite a probable decrease in anthropogenic methane emissions during COVID-19 lockdowns. Here we quantify changes in methane sources and in its atmospheric sink in 2020 compared with 2019. We find that, globally, total anthropogenic emissions decreased by 1.2 ± 0.1 teragrams of methane per year (Tg CH4 yr−1), fire emissions decreased by 6.5 ± 0.1 Tg CH4 yr−1 and wetland emissions increased by 6.0 ± 2.3 Tg CH4 yr−1. Tropospheric OH concentration decreased by 1.6 ± 0.2 per cent relative to 2019, mainly as a result of lower anthropogenic nitrogen oxide (NOx) emissions and associated lower free tropospheric ozone during pandemic lockdowns2. From atmospheric inversions, we also infer that global net emissions increased by 6.9 ± 2.1 Tg CH4 yr−1 in 2020 relative to 2019, and global methane removal from reaction with OH decreased by 7.5 ± 0.8 Tg CH4 yr−1. Therefore, we attribute the methane growth rate anomaly in 2020 relative to 2019 to lower OH sink (53 ± 10 per cent) and higher natural emissions (47 ± 16 per cent), mostly from wetlands. In line with previous findings, our results imply that wetland methane emissions are sensitive to a warmer and wetter climate and could act as a positive feedback mechanism in the future. Our study also suggests that nitrogen oxide emission trends need to be taken into account when implementing the global anthropogenic methane emissions reduction pledge.
de Columba Martínez-Espinosa, Sabine Sauvage, Ahmad Al Bitar, Jose Miguel Sánchez Pérez
In Environmental Modelling and Software, 158 (December, 2022), 12
En ligne : www.sciencedirect.com[...]
The Wetland Soils Denitrification Model (WSDM) developed here for natural wetlands, is a physical based model that proposes: (i) the inclusion of soil moisture and temperature from satellite-based Earth Observations at diurnal temporal resolution and (ii) the distinction of soils under different wetland typologies (i.e., flooded forests, freshwater marshes, brackish wetlands, peatlands, and complex wetlands). Despite uncertainties involved, these two features are key to upscale nitrification/denitrification dynamics in natural wetlands at landscape, regional and global scales. In this study, the performance of WSDM was validated with soils in flooded forests and freshwater marshes in the central Amazonian floodplain. WSDM multiannual time series (2012–2019) show that climate anomalies intensify denitrification events. Flooded forests were identified with the highest annual denitrification rates. Annual denitrification and N2O emissions estimated in this study are in line with previous studies.
de Maxine Thorel, Pierre Marmonier, Céline Bertrand, Cécile Claret, Stéphanie Fayolle, Maxime Logez, Jean-Michel Olivier, Benjamin Oursel, Antonin Vienney, Hervé Piégay, et al.
In Aquatic Sciences, 84(4) (October, 2022), 66
En ligne : doi.org[...]
The importance of artificial wetlands for the biodiversity of the Rhône River floodplain was assessed at twelve stations along two sections of the river. The relative roles of the local characteristics of the wetlands (e.g. available nutrients, dissolved oxygen, sediment quality) and of their connectivity with the main channel were considered for three different groups of organisms (benthic microbes, benthic invertebrates and phytoplankton communities). The functional characteristics of these organisms were determined through their enzymatic activities (for microbes) and biological traits (for invertebrates and phytoplankton). The predicted major role of connections between the wetlands and the river channel was confirmed for environmental characteristics (water and sediment) and benthic invertebrates. Connectivity appeared to be less of a driver of benthic microbial communities and phytoplankton, which were partly or mainly controlled by wetland geometry (water depth, light penetration, and resulting organic matter production). We conclude that connectivity with the river channel needs to be considered jointly with the geometry of wetlands to provide functional solutions when defining management and restoration plans.The Sidi Moussa-Oualidia wetland complex. A Bird Paradise between land and sea
de Rhimou El Hamoumi, Siham El Malki, Abdeslam Rihane, Abedlhak Fahmi, Mohamed Dakki
In Frontiers in Science and Engineering, 12(1) (October, 2022), 65-76
En ligne : revues.imist.ma[...]
The Sidi Moussa-Oualidia wetland complex is a unique natural ecosystem of significant national and international importance, as designated by the Ramsar Convention. Located in the Moroccan Atlantic zone between El Jadida and Oualidia, this wetland fulfils many functions. The most important are the rich biodiversity, ecological, hydrological, and economic functions are the most important. Regular censuses, carried out during winter between 1993 and 2022 in the Sidi Moussa-Oualidia lagoon complex, made it possible to determine the composition of the waterbird population that frequents this site and to define the status of the various encountered species. Emphasis was also made on the value of this complex, particularly for breeding, based on monitoring work and our unpublished observations. Ninety-six (96) species frequented the site, 51 of which are regular. Waders represent the most dominant group, followed by Laridae and Anatidae. The remaining groups, poorly represented in numbers, total some 29 species, of which twelve (12) are accidental or rare, and nine (9) are mainly observed outside the wintering period. However, some species are particularly interesting, such as the Greater Flamingo, the Eurasian Spoonbill, and the Red-knobbed Coot. Of the 51 regular species in the site, 16 are breeding ones, including species classified as threatened or near-threatened on the global red list (Marbled Teal, Ferruginous Duck) and others considered threatened in Morocco (Purple Swamphen, Red-crested Pochard), rare (Little Tern) or remarkable (Red-knobbed Coot). Despite this ornithological richness, the site is subject to multiple constraints. Creating a specific administrative structure similar to an "Agency for the development of the Sidi Moussa-Oualidia complex" could be a potential solution for the control, rational management, and sustainable local development.
Key words: Wetlands, Sidi Moussa-Oualidia lagoons, Waterbirds, Morocco.Impacts of climate change on the dysfunction of Mediterranean wetlands
de Mhamed Khaffou, El Hassan Abba, Abdelkader Chahlaoui
In IOP Conference Series: Earth and Environmental Science, 1090(1) (2022-10-01), 14
En ligne : iopscience.iop.org[...]
The water is a limiting factor for wetlands, especially for those with shallow deep. They are more vulnerable to precipitation disturbance. However, most of these wetlands are suffering from repetitive natural droughts. Example Aguelmam Afennourir wetland classified Ramsar site since 1980. After calculating the Normal Difference Water Index (NDWI), it has undergone severe and repeatedly drying and we have noticed four total dry-outs between 1981 and 2016. It is completely dried in July 1995, July 2000, June 2008, and in November 2016. While its largest extension, 100 % (122 ha) occurred in May 2009, the one before analyzing the historic precipitation for 1981 to 2016 and open water area evolution in the site we have brought that the drying of Aguelmam is closely linked to the irregularity of precipitation. Their drying up causes an ecological disequilibrium and has negative impacts on biodiversity since it has lost water which constitutes the defense of its habitats and biodiversity. Meanwhile, the fauna must leave the site and live the migration risks of searching the living habitat. The analysis of the hydrographic network of the sub-basin in the site reveals the possibility of diverting neighbouring streams toward the Afennourir wetland for heightening its water volume. As a preventive measure to protect the biodiversity of the site and to reduce the anthropogenic action, we propose strengthening the dyke with local materials, to increase the volume and the level of water in the wetland.
de Dilara Arslan, Lisa Ernoul, Arnaud Béchet, Ömer Döndüren, Mehmet Sıkı, Thomas Galewski, Dilara Arslan, Lisa Ernoul, Arnaud Béchet, Ömer Döndüren, et al.
In Marine and Freshwater Research, Online (October, 2022)
En ligne : www.publish.csiro.au[...]
Bird species have been studied and documented abundantly in the past decades and are good indicators of ecosystem conditions, providing useful information of the changes in the ecological state of wetlands over time. However, monitoring data for birds in wetland sites are often disparate and not homogeneous over time and among species, which complicates the interpretation of trends.
We examined historical literature from 1835 to 2019, complemented by an expert knowledge survey and citizen-science databases to estimate the abundance of species, and evaluated changes in the structure and composition by average bird abundances.Key results Our results suggested that land-cover and land-use changes have shaped the local bird community, with a decline in agricultural and grassland bird species as a result of changes in agricultural practices. Coastal wetland and marine birds have increased in abundance, most probably linked to the extension of saltpans and successful conservation measures.
hese trends in bird communities demonstrate the impacts of different land management strategies on biodiversity.Implications This methodology can be replicated in other Ramsar and wetland sites around the world to raise new conservation issues and improve site conservation.
de Sabrine Sahbani, Béchir Béjaoui, Sihem Benabdallah, Rachid Toujani, Afef Fathalli, Noureddine Zaaboub, Jalel Aouissi, Zeineb Kassouk, Nabil Hamdi, Nabiha Ben Mbarek, et al.
In Journal of Sea Research, Online (October, 2022), 102288
En ligne : linkinghub.elsevier.com[...]
Tunisia’s Ichkeul Lake is among the most productive ecosystems in the Mediterranean, with a great regional value thanks to its diversity of habitats. It is an important overwintering area for waterfowl species. It is a RAMSAR wetland, a National Park, a UNESCO World Heritage, and a Biosphere Reserve. This review paper provides a broad overview of the climatic, hydraulic, biogeochemical features, bio-resources, and bio-productivity of the Lake. The interconnectivity between the different environmental components of the lake is presented, highlighting the main characteristics of this vital ecosystem. Its ecosystem consists of a permanent lake bordered by temporary marshes. It is connected to the Mediterranean Sea via Bizerte Lagoon under a typical semi-arid to sub-humid bio-climate with wet and dry seasons. The winter rainfall fills up the rivers and lake with freshwater that overflows into the Tinja River. In summer, high evaporation reduces the water level and allows seawater to enter the wetland from Bizerte Lagoon. The ecosystem is threatened by pollution, the damming of its main rivers, and climate change. The unsustainable water management has resulted in fundamental environmental modifications, as evidenced by the large variation in the salinity, water level, productivity of water plants, and the decline in venue and stop-overs of waterbirds. The current situation is a warning that indicates a general perturbation of the resources of this particular site and of Tunisian wetlands in general, especially that the Mediterranean region has been designated as a climate change hotspot. Accurate hydrological management is needed to boost the physical functioning of the ecosystem, and to gain deeper knowledge of the different phases of the water cycle and its relationship to other long-term environmental cycles for sustainable water management strategies in the most water-scarce region in the world.Importance and Winter Ornithological Value of Lake El-Golea (Ghardaïa, Algerian Sahara
de Biad Radhia, Bounab Choayb, Guergueb El Yamine, Biad Mohamed Fetheddine, Houhamdi Moussa
In Journal of Bioresource Management, 9(3) (September, 2022), 149-62
En ligne : corescholar.libraries.wright.edu[...]
This study is carried out on two winter period (2018-2019 and 2019-2020) in Lake El-Golea (Ghardaïa, northern Sahara of Algeria). Its objective is to determine the ornithological value of this lake and to in ferits importance in maintaining aquatic avifauna during the winter season. This inventory shows a diversity equivalent to forty-one species belonging to thirteen families and nine orders of which eighteen are protected by various Algerian and international laws. The most represented family is that of the Anatidae with twelve species while the family with the highest number is that of the Phenicopteridae represented only by one species, the Greater Flamingo (Phenicopterus roseus). These waterbirds occupy the lake in different ways: the insectivores are distributed on the banks and in the shallow areas of the lake while, the herbivores, polyphages and piscivores are concentrated in the deepest areas and in the centre of the lake. It is important to note, however, the presence of two vulnerable species, the Common Pochard (Aythya ferina) and the Marbled Duck (Marmaronetta angustirostris) and anear-threatened species, the Greater Ring- Ferruginous Duck (Aythya nyroca).
de Carles Ibáñez, Nuno Caiola
In Marine and Freshwater Research, 73(10) (September, 2022), 1246-1254
En ligne : doi.org[...]
Understanding the effects of sea-level rise (SLR) and marine storms on Mediterranean coastal wetlands is crucial to developing adequate climate change adaptation pathways. Because the majority of these systems are in deltaic areas, integrated river basin management (water and sediment discharge) is a must in the design of such pathways. Rising sea levels will tend to gradually flood coastal lagoons and marshes unless there is enough sediment supplied to compensate for the increasing deficit. Although the relationship between climate change and Mediterranean coastal storms is weak or non-existent, their impacts are expected to grow in the context of SLR and coastal squeezing. For example, the most affected Ebro Delta coastal stretches during the Gloria storm (January 2020), one of the most intense ever recorded in the Mediterranean, were those where the beach was narrower and weaker. Hard engineering solutions, such as the construction of dykes, as a protection measure against marine storms are not sustainable under scenarios of climate change and energy scarcity. A management approach based on soft engineering coastal defences and nature-based solutions is the most cost-effective and sustainable in the long run. The adequacy of implementing this kind of solution along the Mediterranean coast is discussed.
de Jacques Nel, Marc Thibault, Thierry Varenne
In RARE. Revue de l'Association roussillonnaise d'entomologie, 31(2) (2022), 120 – 125.
Une nouvelle espèce du genre Hypenodes Doubleday, 1850, liée à des biotopes humides dans les Bouches-du-Rhône (France), Hypenodes occidentalis sp. n., est décrite et essentiellement comparée à H. pannonica Fibiger & al., 2010.Commemorating the 50th anniversary of the Ramsar Convention on Wetlands
de C. Max Finlayson, S. Fennessy, Patrick Grillas, R. Kumar
In Marine and Freshwater Research, 73(10) (September, 2022), i-v
En ligne : doi.org[...]
This issue of Marine and Freshwater Research celebrates 50 years of the Ramsar Convention on Wetlands, which was signed in 1971. It contains papers that describe the development of the Convention and its implementation, including the listing of wetlands of international importance and maintenance of their ecological character. The latter is a fundamental issue for wetland management as illustrated in papers that address a range of management issues, including the impact of climate change, and approaches for building awareness about their values, and concludes with a forward view for potentially reframing human–wetland relationships.
de Brigitte Poulin, Gaëtan Lefebvre, Samuel Hilaire, Laurence Després
In Ecotoxicology and Environmental Safety, 243 (September, 2022), 10
En ligne : linkinghub.elsevier.com[...]
Bacillus thuringiensis subsp. israelensis (Bti) is the main larvicide used to control mosquitoes worldwide. Although there is accumulating evidence of Bti having environmental effects on non-target fauna, relatively few field studies have documented the fate of Bti spores in the environment. Spore density was quantified over a 6-yr period (2012–2017) in Mediterranean marshes sprayed with Vectobac 12AS (32 ITU/ha) since 2006 to reduce the nuisance caused by Aedes caspius. Bti spores were naturally found in all habitat types. Spore density expressed as colony-forming units per gram of soil (CFU g− 1) increased significantly at treated sites by a factor of 22 to 500 times relative to control sites, with mean values of 7730 CFU g− 1 in halophilous scrubs, 38,000 in reed beds, 49,000 in bulrush beds and 50 000 in rush beds. Spore density varied little in the first months after the spraying season (April-October), but increased sharply in spring, just before the annual launch of mosquito control. Considering that Bti is an insect pathogen that cannot proliferate without a suitable insect host, this unexpected recrudescence in spring could be related to the warming of water that triggers activity and development of benthic organisms such as chironomids, which may contribute to Bti proliferation by ingesting accumulated spores at the surface of sediments. While spore density tends to decrease over time, presumably during the summer period as a result of increased UV exposure, three to four years were necessary for spore density to return to normal levels after mosquito-control interruption. This study is important because it demonstrates that environmental effects of mosquito-control using Bti can far exceed the short period of Bti efficacy against lentic mosquitoes. Considering that Bti is a microbial agent, these long-term effects should be addressed at multiple levels of ecosystem organization from a one-health perspective.Use of voluntary environmental contracts for wetland governance in the European Mediterranean region
de Lisa Ernoul, Pablo Vera, Giancarlo Gusmaroli, Serena Muccitelli, Carolina Pozzi, Stefano Magaudda, Katarina Polajnar Horvat, Aleš Smrekar, Alessio Satta, Flavio Monti, et al.
In Marine and Freshwater Research, 73(10) (September, 2022), 8
En ligne : www.publish.csiro.au[...]
Ramsar sites are internationally protected wetlands designated to maintain an international network for biodiversity conservation and sustain human life. There are often conflicting interests for site management that lead to decisions based on sectoral policies or local approaches that have poor outcomes in terms of effectiveness and trade-offs. The European Water Framework Directive (2000/60/EC) requires European countries to foster an integrated approach for wetland management through collaborative governance processes. The environmental contract is a tool that has been developed and implemented to set the ground for voluntary-based commitments for the sustainable governance of water systems. This paper reports on the results of the first study investigating the implementation of voluntary environmental contracts at the Mediterranean European level. Our results indicate that Ramsar sites in the region have made great progress with the development of management plans, yet many sites still lack governance schemes involving stakeholders. Voluntary environmental contracts have been widely used in Ramsar sites in France and Italy, but only a few other European countries have started implementing them. We have identified the need to further adapt the tool to local and national contexts, as well as the need for legislation, to promote upscaling at the regional scale.Attribution of the 2020 surge in atmospheric methane by inverse analysis of GOSAT observations
de Zhen Qu, Daniel J Jacob, Yuzhong Zhang, Lu Shen, Daniel J Varon, Xiao Lu, Tia Scarpelli, Anthony Bloom, John Worden, Robert J Parker
In Environmental Research Letters, 17(9) (2022)
En ligne : iopscience.iop.org[...]
Atmospheric methane mixing ratio rose by 15 ppbv between 2019 and 2020, the fastest growth rate on record. We conduct a global inverse analysis of 2019–2020 Greenhouse Gases Observing Satellite observations of atmospheric methane to analyze the combination of sources and sinks driving this surge. The imbalance between sources and sinks of atmospheric methane increased by 31 Tg a−1 from 2019 to 2020, representing a 36 Tg a−1 forcing (direct changes in methane emissions and OH concentrations) on the methane budget away from steady state. 86% of the forcing in the base inversion is from increasing emissions (82 ± 18% in the nine-member inversion ensemble), and only 14% is from decrease in tropospheric OH. Half of the increase in emissions is from Africa (15 Tg a−1) and appears to be driven by wetland inundation. There is also a large relative increase in emissions from Canada and Alaska (4.8 Tg a−1, 24%) that could be driven by temperature sensitivity of boreal wetland emissions.Rewetting global wetlands effectively reduces major greenhouse gas emissions
de Junyu Zou, Alan D. Ziegler, Deliang Chen, Gavin McNicol, Philippe Ciais, Xin Jiang, Chunmiao Zheng, Jie Wu, Jin Wu, Ziyu Lin, et al.
In Nature Geoscience, 15(8) (August, 2022), 627-632
En ligne : www.nature.com[...]
Carbon and nitrogen losses from degraded wetlands and methane emissions from flooded wetlands are both important sources of greenhouse gas emissions. However, the net-exchange dependence on hydrothermal conditions and wetland integrity remains unclear. Using a global-scale in situ database on net greenhouse gas exchanges, we show diverse hydrology-influenced emission patterns in CO2, CH4 and N2O. We find that total CO2-equivalent emissions from wetlands are kept to a minimum when the water table is near the surface. By contrast, greenhouse gas exchange rates peak in flooded and drained conditions. By extrapolating the current trajectory of degradation, we estimate that between 2021 and 2100, wetlands could result in greenhouse gas emissions equivalent to around 408 gigatons of CO2. However, rewetting wetlands could reduce these emissions such that the radiative forcing caused by CH4 and N2O is fully compensated by CO2 uptake. As wetland greenhouse gas budgets are highly sensitive to changes in wetland area, the resulting impact on climate from wetlands will depend on the balance between future degradation and restoration. Global in situ observations show greenhouse gas emissions from wetlands are lowest when the water table is near the surface, and therefore rewetting wetlands could substantially reduce future emissions.Ominous feedback loop may be accelerating methane emissions
de Paul Voosen
In Science, 377(6603) (July, 2002), 250-251
En ligne : www.science.org[...]
Tropical wetlands, getting wetter with global warming, emerge as hot spots for heat-trapping gasSite fidelity and determinants of wintering decisions in the Dalmatian pelican (Pelecanus crispus)
de Anastasios Bounas, Giorgos Catsadorakis, Theodoros Naziridis, Taulant Bino, Dionyssia Hatzilacou, Myrsini Malakou, Ortaç Onmuş, Mehmet Siki, Pavel Simeonov, Alain J Crivelli
In Ethology Ecology & Evolution, Online (July, 2022), 1-15
En ligne : doi.org[...]
Wintering site selection is a major decision in a bird’s annual life cycle since conditions experienced by individuals within a wintering site can influence individual fitness and ultimately population dynamics. If individuals show strong fidelity to specific sites, annual environmental effects can be reinforced. In this study we analyse winter resightings of ringed Dalmatian pelicans, collected during a 35-year-long ringing survey, to identify winter movement patterns of Dalmatian pelicans, assess the level of site fidelity both within and among consecutive wintering events and examine environmental factors that may contribute to an individual’s decision to move towards a specific site during the winter period. Our results showed that the decision of Dalmatian pelicans to move towards a specific site was mainly driven by the site’s size and temperature conditions. Larger wetlands can provide birds with higher resource abundance and offer more opportunities to exploit optimal roosting and feeding habitats, whereas wetlands that do not freeze during the winter are a definite requirement. Wintering movements were more likely to occur at short distances from a bird’s natal colony, whereas it was uncommon for birds born in wetlands located in the Adriatic and Ionian coast to move eastwards during the winter, suggesting a level of spatial substructure. Furthermore, we showed that the species exhibits very strong within-year and among-year wintering site fidelity, with birds moving less during the winter, whereas juvenile birds travel greater distances than the rest of the age classes examined. Our conclusions could guide an effective approach to site-based conservation management at key wintering sites.The Cassaïre wetland restoration project: defining the reference ecosystem
de Isabelle Muller, Johan Friry, Elise Buisson, François Mesléard
In Ecologia Mediterranea, 48(1) (June, 2022), 10
Defining a reference ecosystem for ecological restoration project is an essential step. The reference can correspond to the historical ecosystem, can be defined to solve environmental issues or can correspond to a socioecosystem. For the restoration of the Cassaïre site in the Camargue delta in southern France, the reference ecosystems chosen are: Mediterranean temporary wetlands and Mediterranean meso-xeric grasslands. The choice of these two reference ecosystems appears logical considering their contribution to regional biodiversity. Temporary wetlands and meso-xeric grasslands are rare, adapted to the Mediterranean climate, seriously endangered and host a high species richness. They are potentially achievable restoration targets because patches of these ecosystems remain in the Camargue area and close to the Cassaïre site. Moreover, an ecological history approach reveals deep human imprints on ecosystems and ensures that historical restoration targets (the state prior to human impacts) cannot be reached, because they are associated with hydraulic functioning (flooding of the Rhône and Durance) that no longer exists. The restored site is planned to be suitable for livestock grazing, thus presenting a new agricultural opportunity, while simultaneously offering new services, such as hunting.
de Stefano Barchiesi, Antonio Camacho, Eva Hernández, Anis Guelmami, Flavio Monti, Alessio Satta, Osvaldo Jordán, Christine Angelini
In Wetlands, 42(5) (June, 2022), 46
En ligne : link.springer.com[...]
Although environmental flow regime assessments are becoming increasingly holistic, they rarely provoke water managers to enact the adaptive water reallocation mechanisms required to secure environmental water for wetlands. The conditions that cause science-based environmental flow assessments to succeed or fail in informing the management of environmental water requirements remain unclear. To begin to resolve these conditions, we used process tracing to deconstruct the sequence of activities required to manage environmental water in four case studies of seasonally ponding wetlands in Mediterranean and Mesoamerican watersheds. We hypothesized that, when the flexibility and equitability of the socioeconomic system do not match the complexity of the biophysical system, this leads to a failure of managers to integrate scientific guidance in their allocation of environmental water. Diagnostic evidence gathered indicates that science-management partnerships are essential to align institutional flexibility and socioeconomic equitability with the system’s ecohydrological complexity, and thus move from determination to reallocation of environmental water. These results confirm that institutions e.g., river basin organizations need to be supplemented by motivated actors with experience and skill to negotiate allocation and adaptive management of environmental water. These institutional-actor synergies are likely to be especially important in water scarce regions when the need to accommodate extreme hydrological conditions is not met by national governance capacity. We conclude by focusing on benefit sharing as a means to better describe the conditions for successful science-based environmental flow assessments that realize productive efficiency in environmental water allocation i.e., recognition of multiple values for both people and ecosystems.
High-resolution mapping of losses and gains of Earth’s tidal wetlands
de Nicholas J. Murray, Thomas A. Worthington, Pete Bunting, Stephanie Duce, Valerie Hagger, Catherine E. Lovelock, Richard Lucas, Megan I. Saunders, Marcus Sheaves, Mark Spalding, et al.
In Science, 376(6594) (May, 2022), 744-749
En ligne : www.science.org[...]
Tidal wetlands are expected to respond dynamically to global environmental change, but the extent to which wetland losses have been offset by gains remains poorly understood. We developed a global analysis of satellite data to simultaneously monitor change in three highly interconnected intertidal ecosystem types—tidal flats, tidal marshes, and mangroves—from 1999 to 2019. Globally, 13,700 square kilometers of tidal wetlands have been lost, but these have been substantially offset by gains of 9700 km2, leading to a net change of −4000 km2 over two decades. The authors found that 27% of these losses and gains were associated with direct human activities such as conversion to agriculture and restoration of lost wetlands. All other changes were attributed to indirect drivers, including the effects of coastal processes and climate change.Groundwater extraction poses extreme threat to Doñana World Heritage Site
de Carlos Camacho, Juan J. Negro, Johan Elmberg, Anthony D. Fox, Szabolcs Nagy, Deborah J. Pain, Andy J. Green
In Nature Ecology & Evolution, Online (April, 2022), 2
En ligne : www.nature.com[...]Spain’s Doñana World Heritage Site in danger
de Juan G. Navedo, Theunis Piersma, Jordi Figuerola, Wouter Vansteelant
In Science, 376(6589) (April, 2022), 144-144
En ligne : www.science.org[...]
de Gema L. Batanero, Andy J. Green, Juan A. Amat, Marion Vittecoq, Curtis A. Suttle, Isabel Reche
In Aquatic Sciences, 84(2) (March, 2022), 22
En ligne : doi.org[...]
Coastal wetlands are valuable aquatic ecosystems with high biological productivity, which provide services such as a reduction in nitrogen loading into coastal waters and storage of organic carbon acting as carbon dioxide sinks. The predicted rise of sea level or freshwater extractions, particularly in the arid Mediterranean biome, will salinize many coastal wetlands. However, there is considerable uncertainty about how salinization will affect microbial communities and biogeochemical processes. We determined the abundance of total prokaryotes, cyanobacteria, and viruses and quantified the heterotrophic production of prokaryotes sensitive- (predominantly Bacteria) and resistant- (predominantly Archaea) to erythromycin in 112 ponds from nine coastal wetlands. We explored the main drivers of prokaryotic abundance and heterotrophic production using generalized linear models (GLMs). The best GLM, including all the wetlands, indicated that the concentration of total dissolved nitrogen (TDN) positively affected the total abundance of prokaryotes and the heterotrophic erythromycin-resistant (ery-R) production. In contrast, heterotrophic erythromycin-sensitive (ery-S) production was negatively related to TDN. This negative relationship appeared to be mediated by salinity and virus abundance. Heterotrophic ery-S production declined as salinity and virus abundance increased. Consequently, we observed a switch from heterotrophic ery-S production towards ery-R production as salinity and virus abundance increased. Our results imply that microbial activity will change from heterotrophic bacterial-dominated processes to archaeal-dominated processes with anthropogenic nitrogen and salinization increases. However, more studies are required to link the mineralization rates of dissolved nitrogen and organic carbon with specific archaeal taxa to enable more accurate predictions on future scenarios in coastal wetlands.
de Alaaeldin Soultan, Diego Pavon-Jordan, Ute Bradter, Brett K. Sandercock, Wesley M. Hochachka, Alison Johnston, Jon Brommer, Elie Gaget, Verena Keller, Peter Knaus, et al.
In Environmental Research Letters, 17(2) (February, 2022), 024025
En ligne : doi.org[...]
Wetland bird species have been declining in population size worldwide as climate warming and land-use change affect their suitable habitats. We used species distribution models (SDMs) to predict changes in range dynamics for 64 non-passerine wetland birds breeding in Europe, including range size, position of centroid, and margins. We fitted the SDMs with data collected for the first European Breeding Bird Atlas and climate and land-use data to predict distributional changes over a century (the 1970s–2070s). The predicted annual changes were then compared to observed annual changes in range size and range centroid over a time period of 30 years using data from the second European Breeding Bird Atlas. Our models successfully predicted ca. 75% of the 64 bird species to contract their breeding range in the future, while the remaining species (mostly southerly breeding species) were predicted to expand their breeding ranges northward. The northern margins of southerly species and southern margins of northerly species, both, predicted to shift northward. Predicted changes in range size and shifts in range centroids were broadly positively associated with the observed changes, although some species deviated markedly from the predictions. The predicted average shift in core distributions was ca. 5 km yr−1 towards the north (5% northeast, 45% north, and 40% northwest), compared to a slower observed average shift of ca. 3.9 km yr−1. Predicted changes in range centroids were generally larger than observed changes, which suggests that bird distribution changes may lag behind environmental changes leading to ‘climate debt’. We suggest that predictions of SDMs should be viewed as qualitative rather than quantitative outcomes, indicating that care should be taken concerning single species. Still, our results highlight the urgent need for management actions such as wetland creation and restoration to improve wetland birds’ resilience to the expected environmental changes in the future.
de Ismahan Halassi, Ali Elafri, Lamia Boutabia, Salah Telailia
In African Journal of Ecology, Online (2022)
En ligne : onlinelibrary.wiley.com[...]
Understanding the factors affecting escape behaviour in waterbirds can be useful in the management of human disturbances. A common measure of escape response is flight initiation distance (FID), the distance at which an approaching intruder disturbs an individual bird enough to make it move away. Here, we analyse the escape behaviour of a set of waterbirds for the first time within a North African context. We tested (one-way ANOVA and general linear model) how FID varied with the area where waterbirds were temporal scale, distance at which the observer start approaching to the sampled birds, body size, flock size, species composition of the flock and foraging activity of the sampled birds. We collected 866 individual FIDs for 19 waterbird species wintering at two north Algerian wetlands (the Mekhada marsh, RAMSAR site, El-taref District and the Sebkhet El-Mahmel, unprotected wetland, Khenchela District). The obtained FIDs ranged from 32.6 m in smaller species as the Kentish plover Charadrius alexandrines to 167 m in larger ones as the ruddy shelduck Tadorna ferruginea. The obtained models stated that differences in the absolute levels of FIDs were mostly related to starting distance (Effect size = 0.62), to which is added a relatively little effect of wetland status, taxonomic differences, temporal scale, body size, flock size, species composition of the flock and bird activity. More specifically, FID was lower in smaller and homospecific groups at early winter in the protected wetland. Reserve managers in North Africa could use species and context-specific FIDs in delineating appropriate buffer areas and in the design of management initiatives aimed at minimising eventual potential threat due to human disturbance and guaranteeing animal welfare and wildlife.
de Julien Birard, Pierre Defos du Rau, Clémence Gaudard, François Guerquin, François Lamarque, Jean-Philippe Siblet, Jean-Yves Mondain-Monval
In European Journal of Wildlife Research, 68(1) (January, 2022), 8
En ligne : link.springer.com[...]
Abundance of wild species is generally used to prioritize and evaluate networks of protected areas (PAs). Waterbird abundance information, collected through the International Waterbird Census (IWC), is widely used to identify key sites for migratory waterbirds, which are listed in the Critical Site Network (CSN) database. We reviewed IWC information, as well as national and local surveys of breeding populations, for each significant wetland and each waterbird species in all French territories within the African-Eurasian Migratory Waterbird Agreement range. We used this review to update the French network of critical sites. We then confronted these waterbird data with the corresponding site-specific data provided by the CSN in order to assess its accuracy for French critical sites. In addition, these waterbird data were used to assess the efficiency of the current network of French PAs to encompass these critical sites, with a particular focus on Ramsar wetlands. We updated the French list of critical sites from the outdated 129 sites listed by the CSN to only 97, including 32 sites not previously detected by the CSN. We also showed that only one French critical site out of five benefits from the strongest category of protection over more than three-quarters of its area. Furthermore, almost one critical site out of five has no protection at all over more than half of its area. The French network of critical sites thus lacks adequate protection, including for some of the most important ones in terms of waterbird abundance and diversity. We advocate for a renewed French effort in wetland conservation and support to the CSN tool maintenance.Threat Ranking to Improve Conservation Planning: An Example from the Gediz Delta, Turkey
de Dilara Arslan, Kerim Cicek, Ömer Döndüren, Lisa Ernoul
In Land, 10(12) (December, 2021), 16
En ligne : www.mdpi.com[...]
Mediterranean wetlands are among the most threatened natural areas. The needs and demands of an increasing human population are modifying land use and converting natural habitats into artificial areas. In order to combat these trends, effective conservation planning needs to provide clear, systematic identification of threats to find sustainable conservation strategies. In this case study, we evaluated current threats in the Gediz Delta (Turkey) using a multi-method approach. First, we did a comprehensive literature review and stakeholder interviews to identify existing threats. We then did a complete survey of the Delta through intensive fieldwork. The threats were coded and ranked using the conservation standards. We used the threat ranking and field survey to map the most vulnerable areas of the Delta. The most commonly observed threats in the field were pollution and agriculture and aquaculture activities. According to the threat ranking, the most important threats are climate change and residential and commercial development. The habitats that are most at risk are agricultural grassland habitats. The results indicate a need to extend conservation actions in the inner part of the Delta. In addition, the multi-method threat ranking approach could serve as a model to improve conservation planning in other sites worldwide.Results of the January 2021 waterbird census in Slovenia
de Luka Bozic
In Acrocephalus, 42(190-191) (2021), 79-93
En ligne : sciendo.com[...]
nullThe future of temporary wetlands in drylands under global change
de Gema Parra, Francisco Guerrero, Javier Armengol, Luc Brendonck, Sandra Brucet, C. Max Finlayson, Luciana Gomes-Barbosa, Patrick Grillas, Erik Jeppesen, Fernando Ortega, et al.
In Inland Waters, Online (November, 2021), 1-12
En ligne : www.tandfonline.com[...]
The Andalusian International University held a workshop entitled Temporary wetlands’ future in drylands under the projected global change scenario in March 2020 in Baeza, Spain, with 26 participants from 10 countries. The workshop objectives were to promote international cooperation and scientific exchange on the conservation and protection of temporary wetlands. The participants highlighted the extreme conditions that temporary and permanent wetlands, ponds, and shallow lakes are currently facing and predicted a dismal future for these systems due to climate change. To foster a holistic view of these ecosystems, the workshop included wetland watersheds. It was concluded that the main threats are those affecting water quality and quantity as well as egg-seed banks, species population dynamics, and food webs. The inherent characteristics of waterbodies in drylands, including high resilience and resistance to harsh conditions, are already negatively impacted by direct human actions and climate change. Another threat is the time lag between scientific warnings about threats and the social and political concern leading to mitigating actions. Thus, more effective actions to protect and conserve temporary wetlands are essential. Research networks could help stimulate the necessary conservation actions, but the global recession due to the COVID-19 pandemic will pose a challenge as economies are burdened with urgent expenditure. This special issue of the journal Inland Waters is the outcome of the workshop presentations and is composed of the ensuing papers on wetlands in drylands.Foreseen impact of climate change on temporary ponds located along a latitudinal gradient in Morocco
de Patrick Grillas, Laïla Rhazi, Gaëtan Lefebvre, Mohammed El Madihi, Brigitte Poulin
In Inland Waters, Online (Septembre, 2021), 1-16
En ligne : www.tandfonline.com[...]
Wetlands have been declining worldwide, with an estimated 64–71% loss over the last century. Climate change is increasing pressure on wetlands, affecting their hydrology, and Mediterranean temporary ponds could be particularly vulnerable to these changes. We studied the expected changes in hydrology and plant community according to climatic change scenarios in 18 temporary ponds distributed in 6 areas along a latitudinal and climatic gradient in Morocco (750 km; 4° latitudinal gradient). Richness of pond species was significantly correlated with water level and pond hydroperiod and showed a strong decline from north to south along with increased water stress. Using the Mar-O-Sel software (mar-o-sel.net), we simulated the future evolution of water balance and wetland hydroperiod (duration and frequency of flooding) in these ponds for mid- and late-21st century. Climate projections were estimated based on 2 Representative Concentration Pathway (RCP) scenarios assuming a stabilization (RCP4.5) or increase (RCP8.5) in greenhouse gas emissions. The mean water deficit of the ponds currently ranges between −1380 and −1812 mm/yr and would increase by 16–67% in 2100 under the RCP8.5 scenarios. Pond richness is expected to decrease by 8–15 species in 2100, depending on area, as a result of shorter projected hydroperiods. Severity of change was not related to location of the ponds along the latitudinal (aridity) gradient, but rather to the interaction between the size of their catchment area and the thickness of the permeable soil layer.Diversity and Structure of Nesting Birds in the Coastal Riparian Zones of Great Kabylia in Algeria
de K. Hachour, N. Talmat-Chaouchi, R. Moulai
In Zoodiversity, 55(4) (25/08/2021), 10
En ligne : ojs.akademperiodyka.org.ua[...]
Diversity and Structure of Nesting Birds in the Coastal Riparian Zones of Great Kabylia in Algeria. Hachour, K., Talmat-Chaouchi, N., Moulaï, R. — The study of the nesting birds of the coastal riparian zones in Great Kabylia in Algeria, allowed us to identify 45 species of birds, belonging to 12 orders and 26 families. The richest site in terms of species is Takdempt (31 species). The lowest diversity is noted at the level of Boudouaou wadi with 16 species. The values of the Shannon-Weaver diversity index (H’) for all sites are quite high (≥ 3 bits). Concerning the global abundance of avifauna, the site that represents the highest centesimal frequency is that of Takdempt (20.87 %) and this is due to the presence of a colony of Bubulcus ibis (Linnaeus, 1758). The bird communities of the sampled sites are not identical, but the degree of similarity, in general, is quite high (≥ 50 %). The main factors controlling the diversity and the structure of the avifauna of Great Kabylia coastal riparian zones are represented by vertical and horizontal vegetation structure.
Coastal riparian zones
nesting birds
AlgeriaImportant Study Of Terrestrial Entomofauna of a Ramsar site
de M Slim, N Zouaki, H Lougraimzi, L Elghali, L Zidane, M Fadli
In Medicinal Plants Expertise, Online (August 2021)
En ligne : botanicmedicinal.com[...]
The region of Sidi Boughaba which is an important biological reserve (Northwest of Mehdia, Morocco) offers a favorable conditions for the development of diversity of the wildlife. It is characterized by a sub- humid bioclimate and a mild winter. The objective of the present study is to make an entomological inventory in five different areas of floristic cortege perspective (herbaceous, shrub) and other medium (soil, water). A statistical study was performed by environmental indices of composition and structure.
Sampling was done from mid-April 2013 to December 2013. The analysis of the entomofauna revealed the existence of 73 species distributed in 7 Systematic orders and 28 families. Beetles are represented by 19 species, Orthoptera by 13, Diptera by 12 species; Hemiptera, Hymenoptera and Lepidoptera are represented by 8 species for each; Odonata come in last place with 5 species. Similarly, the results showed that the values of Shannon-Weaver diversity vary between 2.654 and 3.411 which express the diversity of the sampled population.
de Nadège Popoff, Elie Gaget, Arnaud Béchet, Laura Dami, Pierre Defos Du Rau, Ilse Geijzendorffer, Anis Guelmami, Jean-Yves Mondain-Monval, Christian Perennou, Marie Suet, et al.
In Biodiversity and conservation, 30 (July, 2021), 19
En ligne : link.springer.com[...]
The Mediterranean Basin is a biodiversity hotspot. Wetlands make a key contribution to this status, but many of them remain outside the Ramsar network fifty years after the establishment of the Ramsar Convention. Here we evaluate the extent to which the Mediterranean Ramsar network covers wetlands of international importance for wintering waterbirds using the Ramsar Convention criteria 2 (species of conservation concern), 5 (> 20,000 waterbirds) and 6 (1% of a population). These criteria were applied to 4186 sites in 24 Mediterranean countries using counts of 145 wintering waterbird species from 1991 to 2017. We identified 161 sites of international importance for waterbirds that have not yet been declared as Ramsar sites, which could be added to the 180 current Mediterranean Ramsar sites established based on waterbird criteria (criteria 5 and/or 6). Among these sites, a subset of 32 very important sites reached double the required level for at least one criterion and 95 were not protected by any site conservation status. Coastal wetlands represented half of the Ramsar gap for waterbirds. We identified that an additional 1218 monitored sites could be provisionally considered as internationally important and thus require more survey efforts to assess their status. This study highlights a lack of participation of the Mediterranean countries to build the Ramsar network for wetland protection. Our results should help policymakers and managers to prioritize future Ramsar site designation, notably in the Middle East and Western European region where important gaps were identified.Bats and wetlands: synthesising gaps in current knowledge and future opportunities for conservation
de Maria Mas, Carles Flaquer, Hugo Rebelo, Adrià López‐Baucells
In Mammal Review, 51(3) (July, 2021), 369-384
En ligne : onlinelibrary.wiley.com[...]
Wetland areas have decreased by up to 33% globally over the past ten years, threatening the biodiversity they support and essential ecosystem services they provide. Despite this, the importance of wetlands for bat conservation and the consequences of losing these habitats are not comprehensively understood.
Through a systematic literature review, we quantified the knowledge gaps regarding bats in wetlands by: 1) assessing research trends over time; 2) evaluating research biases in geography, themes, species, seasons, and methodology; 3) creating the ‘bat Knowledge Index’ (bKI), a standard indicator for measuring how well-studied bats in wetlands are per country; 4) compiling and summarising the ecological responses of bats to wetlands; and 5) assessing how bat researchers perceive the role of wetlands for bat conservation.Perceived wetland wildlife in a North African urban setting: conservation implications
de Abdallah Aouadi, Farrah Samraoui, Awatif Talbi, Lynda Souiki, Boudjema Samraoui
In Bulletin de la Société zoologique de France, 146(2) (2021), 87-94
En ligne : www.societe-zoologique.fr[...]
Using a questionnaire approach, we investigated the perceptions of local residents towards the wildlife of an urban pond. The survey was conducted against the backdrop of an ongoing decrease of the waterfowl and widespread poaching practices. Results revealed that birds were the most attractive wildlife component of the wetland ecosystem, suggesting that birds may successfully be used as flagship species for local conservation programs. In addition, 65% of the respondents believed that a decline in waterfowl had occurred in the last decade, and 74% confirmed that poaching was an ongoing practice, thus revealing an acute awareness of their environment. While mitigation efforts such as improving livelihood and empowering local residents cannot be understated, the sustainable management of North African urban wetlands still requires more insights into socio-economic and ecological issues.Coastal wetlands mitigate storm flooding and associated costs in estuaries
de Tom P. Fairchild, William G. Bennett, Greg Smith, Brett Day, Martin W. Skov, Iris Möller, Nicola Beaumont, Harshinie Karunarathna, John N. Griffin
In Environmental Research Letters, 16(7) (July, 2021), 074034
En ligne : doi.org[...]
As storm-driven coastal flooding increases under climate change, wetlands such as saltmarshes are held as a nature-based solution. Yet evidence supporting wetlands’ storm protection role in estuaries—where both waves and upstream surge drive coastal flooding—remains scarce. Here we address this gap using numerical hydrodynamic models within eight contextually diverse estuaries, simulating storms of varying intensity and coupling flood predictions to damage valuation. Saltmarshes reduced flooding across all studied estuaries and particularly for the largest—100 year—storms, for which they mitigated average flood extents by 35% and damages by 37% ($8.4 M). Across all storm scenarios, wetlands delivered mean annual damage savings of $2.7 M per estuary, exceeding annualised values of better studied wetland services such as carbon storage. Spatial decomposition of processes revealed flood mitigation arose from both localised wave attenuation and estuary-scale surge attenuation, with the latter process dominating: mean flood reductions were 17% in the sheltered top third of estuaries, compared to 8% near wave-exposed estuary mouths. Saltmarshes therefore play a generalised role in mitigating storm flooding and associated costs in estuaries via multi-scale processes. Ecosystem service modelling must integrate processes operating across scales or risk grossly underestimating the value of nature-based solutions to the growing threat of storm-driven coastal flooding.
de N. Bouali, A. Baaloudj, M. Touarfia, I. Houhamdi, M. C. Maazi, M. Houhamdi
In Arxius de Miscel-lània Zoològica, 19 (July, 2021), 135-149
En ligne : amz.museucienciesjournals.cat[...]
Understanding the spatial and temporal niche of waterfowl is essential for effective management and conservation. To determine the ecology and phenology of Anatidae in North Africa, we carried out a 12–month study (2019–2020) in three wetlands that constitute a winter refuge for waterbirds in the Souk–Ahras region in north–east Algeria. We surveyed species richness, the seasonal pattern of the number of Anatidae, and their wintering diurnal behavior using regular counts and scans. We recorded thirteen species: six wintering species (Anas clypeata, Anas penelope, Anas strepera, Tadorna tadorna, Aythya ferina, and Anas crecca crecca) and three sedentary nesting species (Anas platyrhynchos, Oxyura leucocephala, and Aythya nyroca), the latter two having national and international protection status. The survey showed that the wintering behavior of all these species is dominated by sleep, which on average accounts for almost half of the total time (48.91 %). Our results indicate that the three wetlands host a complex waterfowl community that includes species of conservation concern and that these sites likely play an essential role in providing the essential resources for wintering.
Dataset published through GBIF (Doi: 10.15470/fozdot)
de Vincent Roubeix, Lucie Attia, Rémy Chavaux, Frank Very, Anthony Olivier, Luc Ector, Véronique Vassal
In Advances in Oceanography and Limnology, 12(1) (July 2021)
En ligne : www.pagepressjournals.org[...]
Periphytic diatoms growing on aquatic turtle carapaces provide an interesting example of biofouling on an animal substrate. This study dealt with the question of the specificity of epizoic diatom communities for the case of the European pond turtle (Emys orbicularis) and across five water bodies in South-Eastern France. 375 diatom taxa have been identified on the European pond turtle carapace. The results showed that the epizoic communities of the five sites were significantly different from each other. The epizoic diatom communities could be clearly distinguished from epilithic and epiphytic communities only in two out of five sites. The differences in composition at the two sites resulted from the greater abundance of some species and life forms. However, the characteristic pattern of diatom communities on the carapaces was not the same at the two sites. It therefore appeared that the European pond turtle’s carapace did not harbour specific diatom communities and can rather be considered a neutral substrate.Endorheic Waterbodies Delineation From Remote Sensing as a Tool for Immersed Surface Topography
de Carole Delenne, Jean-Stephane Bailly, Antoine Rousseau, Renaud Hostache, Olivier Boutron
In IEEE Geoscience and Remote Sensing Letters, Online (May, 2021), 1-5
En ligne : ieeexplore.ieee.org[...]
For several decades, it becomes possible to delineate waterbodies and their dynamics from optical or radar images, that are now available at high spatial and temporal resolutions. We present here an interpolation approach that takes benefits from this waterbodies delineation in endorheic areas. It consists in computing isovalue contour lines to improve topography estimates classically obtained from measurement points only. The approach, based on a minimization problem, uses thin plate spline (TPS) interpolation functions, the coefficients of which are determined along with the unknown water level of each curve. Results obtained on a generated topography show that this approach, applied with three contour-line curves, yields a lower root mean square error (RMSE) using only one measurement point compared to the one obtained with nine points and the classical approach.
de F. Khirani–Betrouche, R. Moulai
In Arxius de Miscel-lània Zoològica, 19 (July, 2021), 99–111
En ligne : amz.museucienciesjournals.cat[...]
Between 2017 and 2019, 42 species of wintering waterbirds were recorded in the wetland complex of the Oued Righ valley in the Algerian Sahara. The intersite amplitudes of salinity explained the variations in species richness and distribution of waterbirds in the various wetlands studied. Oligohaline (0.5-5 ‰) and mesohaline (5-18 ‰) environments, represented by Lake Ayata, Lake Sidi Khelil and Oued Kherouf, were the most favorable to Anatidae with the exception of the tadornes where their presence was noted in the euhaline (30-40 ‰) and hyperhaline stations (> 40 ‰). The presence of the greater flamingo Phoenicopterus roseus and the slender-billed gull Chroicocephalus genei stood out in the most holomorphic areas of the complex, such as Chott Merouane.
de Dilara Arslan, Anthony Olivier, Lisa Ernoul, Arnaud Béchet, Kerim Cicek
In Zoology in the Middle East, 67(3) (July, 2021), 1-12
En ligne : www.tandfonline.com[...]
The Spur-thighed tortoise (Testudo graeca) is listed as vulnerable on the IUCN Red List, with small and fragmented populations located around the Mediterranean basin. In Turkey, this species has remained poorly studied which hampers solid assessment of threats and conservation measures. We studied the spatial distribution, habitat use, and demography of the species in the Gediz Delta (Aegean coast of Turkey) between 2015 and 2017 with a specific capture-mark-recapture survey made in the Sazlıgöl marshes. A total of 114 individuals (20 juveniles, 62 males and 32 females) were captured and released in that period. Carapace length of adult females was on average higher (205.2±3.2 mm) than in adult males (190.9±2.3 mm). Sex ratio was biased with 1.94 males per female. Based on the capture-recapture histories of 65 individuals (3 juveniles, 37 males and 25 females) marked in 2015, we estimated the population size of the Sazlıgöl marsh population to be 137±23 individuals, which corresponds to a density of 5.7 individuals per ha. The main threats detected were agricultural activities, urbanisation and captures for the pet trade.
de Abdallah Aouadi, Farrah Samraoui, Laïd Touati, Riad Nedjah, Lynda Souiki, Boudjema Samraoui
In Wetlands, 41(6) (June, 2021), 85
En ligne : doi.org[...]
Investigating how Mediterranean wetlands respond to adjacent land use conversion, is an important first step in mitigating the impact of human encroachment and other environmental stressors. We monitored the composition and structure of waterbird assemblages, in a Mediterranean urban marsh, subjected to severe anthropogenic pressures. Remote sensing indicated that in the last two decades Boussedra Pond was subjected to landfill, resulting in a substantial reduction (~ 50 %) of the marsh, while due to a lack of urban planning urban built-up and agriculture areas expanded considerably in its surroundings. This precipitous reduction of the size of this urban pond threatens the diversity of its resident waterbirds which include the globally Endangered (EN) White-headed Duck Oxyura leucocephala, the Near-Threatened (NT) Ferruginous Duck Aythya nyroca, and many other staging and wintering migratory species. The long-term study suggested that breeding waterbirds species responded differentially to the loss and degradation of the marsh, as highlighted by the apparent resilience of the synanthropic Moorhen Gallinula chloropus and the disappearance of several breeding marsh specialists, such as the Little Bittern Ixobrychus minutus and the Western Marsh Harrier Circus aeruginosus. The study also points out the need for both a coordinated cross-sectorial land use planning and an immediate, affordable and sustainable wetland conservation action.
de Alba Cuena-Lombraña, Mauro Fois, Annalena Cogoni, Gianluigi Bacchetta
In Wetlands, 41(6) (June, 2021), 69
En ligne : doi.org[...]
Plants are key elements of wetlands due to their evolutionary strategies for coping with life in a water-saturated environment, providing the basis for supporting nearly all wetland biota and habitat structure for other taxonomic groups. Sardinia, the second largest island of the Mediterranean Basin, hosts a great variety of wetlands, of which 16 are included in eight Ramsar sites. The 119 hydro- and hygrophilous vascular plant taxa from Sardinia represent the 42.6% and 37.9% of the number estimated for Italy and Europe, respectively. Moreover, around 30% of Sardinia’s bryological flora, which is made up of 498 taxa, is present in temporary ponds. An overview at regional scale considering algae is not available, to our knowledge, even though several specific studies have contributed to their knowledge. In order to find the most investigated research themes and wetland types, identify knowledge gaps and suggest recommendations for further research, we present a first attempt to outline the work that has been hitherto done on plants in lentic habitats in Sardinia. Three plant groups (algae, bryophytes and vascular plants), and five research themes (conservation, ecology, inventory, palaeobotany and taxonomy) were considered. After a literature review, we retained 202 papers published from 1960 to 2019. We found that studies on vascular plants, as plant group, were disproportionately more numerous, and inventories and ecology were the most investigated research themes. Although efforts have recently been made to fill these long-lasting gaps, there is a need for updating the existing information through innovative methods and integrative approaches.
de Louisiane Burkart, Anthony Olivier, Olivier Lourdais, Marion Vittecoq, Gabriel Blouin‐Demers, Fabrice Alliot, Clément Le Gac, Nicolas Martin, Aurélie Goutte
In Environmental Toxicology and Chemistry, 40(8) (May, 2021)
En ligne : setac.onlinelibrary.wiley.com[...]
Many banned persistent organic pollutants (POPs) remain for decades in the aquatic environment and can have harmful effects on long-lived predators because of their high bioaccumulation and biomagnification potentials. We investigated the occurrence and levels of 18 polychlorinated biphenyls (PCBs) and 16 organochlorine pesticides (OCPs) in European pond turtles (n = 174) from April to July 2018 in the Camargue wetland, France. Although the Camargue was highly contaminated in previous decades, plasma occurrence and levels of POPs were very low: we were able to quantify only three of the 34 compounds we analyzed in more than 10% of the turtles. POP burdens did not differ between males and females and were uncorrelated with sampling date and body mass. We observed differences in POP burdens between turtles from the two sampling sites. One possible explanation is that the sampling sites were in different agricultural hydraulic system: plasma occurrence and levels were higher for PCB-52 and HCB in turtles captured in drainage channels, and for PCB-153 at the site that receives irrigation. Finally, the occurrence and levels of PCB 153 in turtles increased with age, likely because of bioaccumulation and much higher exposure 20-30 years ago than now. This article is protected by copyright. All rights reserved.
de Azarnia Sabah, Ziane Nadia, Benyacoub Slim
In Ecology, Environment and Conservation, 27(May Suppl. Issue) (May, 2021), 244-250
En ligne : www.envirobiotechjournals.com[...]
The monitoring of the numbers of Eurasian wigeon and gadwall ducks during two winter cycles (2014/ 2015 and 2015/2016) at Lake Tonga, shows that Eurasian wigeon is an early overwinter; this duck is very sensitive to the cold wave. . The gadwall is a late overwinter. Lake Tonga is classified as a nationally and internationally important wintering site for both species. The numbers recorded in 2014/2015 are higher than in 2015/2016, the drop in numbers is explained by climate change (the heat wave that reigned in Europe this year). The study of the diurnal behavior of the two species of Anatidae during their wintering at Lake Tonga showed that the two ducks exploit the studied site as a foraging area.Small ponds support high terrestrial bird species richness in a Mediterranean semiarid region
de José M. Zamora-Marín, Antonio Zamora-López, Maria V. Jimenez-Franco, Jose F. Calvo, Francisco J. Oliva-Paterna
In Hydrobiologia, 848(7) (April, 2021), 1623-1638
En ligne : link.springer.com[...]
Ponds are among the world’s most endangered freshwater ecosystems. A comprehensive knowledge of pond biodiversity is urgently required to inform effective pond management and conservation actions. Most studies about pond biodiversity focus on aquatic taxa, while the terrestrial biodiversity, especially of birds, has been little studied. Moreover, the few studies existing on pond biodiversity do not account for different detection rates of species, thus yielding biased results. Here, we apply a hierarchical Bayesian modelling technique to data obtained from visual censuses to estimate bird species richness associated with small ponds in a semiarid region, considering the imperfect detection of species.Nest site selection and breeding ecology of the Ferruginous Duck (Aythya nyroca) in Algeria
de Karim Loucif, Mohamed Cherif Maazi, Moussa Houhamdi, Haroun Chenchouni
In Global Ecology and Conservation, 26 (April, 2021), 20
En ligne : www.sciencedirect.com[...]
Ecologically, the Nature Reserve of Tonga Lake (northeastern Algeria) is very important for waterbirds. This study investigates breeding biology of an emblematic species of this region: The Ferruginous Duck (Aythya nyroca), a duck ranked globally 'Near Threatened' on the IUCN Red List. This study aimed to determine wetland environmental variables influencing nest site selection and breeding success of the species. Over two successive breeding seasons (2016 and 2017), the effects of habitat characteristics and nest traits on breeding parameters of 50 nests constructed on alder carr of the lake and offshore floating vegetation islets in the center of the waterbody were analyzed using generalized linear models (GLM). Clutch size averaged 9.8 ± 0.7 eggs (range: 2–26 eggs) with 66% hatching success. Desertion of the nest (i.e. nest abandonment by the parents during the period of egg-laying and/or incubation) was the main cause for breeding failure (18% of total nests). Clutch size was positively related to nest surface and nest depth, but it decreased with the increase in the distance of nest on the vegetation platform to water. GLM revealed that breeding success was positively associated with late clutches; with a negative effect of conspecific nest density on clutch size and breeding success. Nest-site choice is resulted from interspecific competition and/or is affected by the reduced number of favorable nesting sites. Nine nests (18%) were parasitized by the same species of which 67% were central nests. Only 2% of the nests studied were parasitized by Oxyura leucocephala nesting at the site. Possible explanations of nest site selection of Aythya nyroca in the study area are discussed. Variations in selection pressures may explain the relationships between the choice and characteristics of nest site in the Ferruginous duck at Lake Tonga.
de Karima Es Salai, Ismail Mansouri, Wafae Squalli, AbdErahim El Hssani, Mohamed Dakki, Nasser Eddine Zine
In Journal of Animal Behaviour and Biometeorology, Online (2021), 0–0
En ligne : www.jabbnet.com[...]
The current study aimed to investigate the nesting behavior and breeding chronology of the crested coot (Fulica cristata) in Morocco’s high altitude wetlands. We monitored nesting activities and breeding phenology in two wetlands, Zerrouka and Hachlaf lakes, to achieve our goals. Besides, nesting materials and nest dimensions were analyzed to characterize the crested coot nests. As a result, 52 nests were found in two sites, 18 in Zerouka and 34 in Hachlaf. Nests were built by available twigs on each site, and nest dimensions varied between analyzed wetlands. Nests were larger in Zerrouka compared to Hachlaf Lake. To protect their nests, coots select open waters and submerged vegetation as nesting sites. On the other hand, breeding chronology, including nesting, laying, and hatching dates, was earlier in Zerrouka Lake than Hachlaf. The nesting activities started at Zerrouka during January and February, while at Hachlaf, breeding attempts started during April.Nest success and nest site selection of wetland birds in a restored wetland system
de Auriel Fournier, Joseph Lancaster, Aaron Yetter, Christopher Hine, Tyler Beckerman, Jacob Figge, Antonio Gioe, Macayla Greider-Wagner, Devin Jen, Cody Johnson, et al.
In Avian Conservation and Ecology, 16(1) (March, 2021)
En ligne : www.ace-eco.org[...]
Fournier, A. M. V., J. D. Lancaster, A. P. Yetter, C. S. Hine, T. Beckerman, J. Figge, A. Gioe, M. Greider-Wagner, D. Jen, C. Johnson, M. R. Larreur, A. Shaw, K. Wolter, M. Wood, D. K. Wu, B. J. O'Neal, and H. M. Hagy. 2021. Nest success and nest site selection of wetland birds in a restored wetland system. Avian Conservation and Ecology 16(1):6. https://doi.org/10.5751/ACE-01782-160106Ramsar Wetlands of International Importance–Improving Conservation Outcomes
de R. T. Kingsford, G. Bino, C. M. Finlayson, D. Falster, J. A. Fitzsimons, D. E. Gawlik, N. J. Murray, Patrick Grillas, R. C. Gardner, T. J. Regan, et al.
In Frontiers in Environmental Science, 9 (March, 2021)
En ligne : www.frontiersin.org[...]
The Ramsar Convention, signed in 1971, was one of the first international conservation agreements, promoting global wise use of wetlands. It has three primary objectives: national designation and management of wetlands of international importance; general wise use of wetlands; and international cooperation. We examined lessons learnt for improving wetland conservation after Ramsar’s nearly five decades of operation. The number of wetlands in the Ramsar Site Network has grown over time (2,391 Ramsar Sites, 2.5 million km2, as at 9/6/20) but unevenly around the world, with decreasing rate of growth in recent decades. Ramsar Sites are concentrated in countries with a high GDP and human pressure (e.g. western Europe) but, in contrast, Ramsar sites with the largest wetland extent are in central-west Africa and South America. We identified three key challenges for improving effectiveness of the Ramsar Site Network: increasing wetland area; improved representation (functional, geographical and biological) and effective management and reporting. Increasing area in the Ramsar network could benefit from targets, implemented at national scales. Knowledge of representativeness is inadequate, requiring analyses of functional ecotypes, geographical and biological representativeness. Finally, most countries have inadequate management planning and reporting on the Ecological Character of their Ramsar Sites, requiring more focused attention on a vision and objectives, with regular reporting of key indicators to guide management. There are increasing opportunities to rigorously track ecological character, utilizing new tools and available indicators (e.g. remote sensing). It is critical that the world protect its wetlands, with an effective Ramsar Convention at the core.
de Daniel Morant, Christian Perennou, Antonio Camacho
In Applied Sciences, 11(4) (February, 2021), 23
En ligne : www.mdpi.com[...]
The features of lentic waterbodies largely depend on the surrounding environment. Mediterranean coastal lagoons have been historically altered, with their catchment being highly modified for agricultural, livestock, or urban uses. Changes in land uses induce pressures that impact the waterbodies and alter their ecological status. The objectives of this paper were: to develop a methodological approach (LUPLES: Land Uses for estimating Pressure Levels to approach the Ecological Status), to quantify the main pressures on the waterbodies and to forecast the possible impacts of these pressures on their ecological status. Corine-Land Cover maps and Geographic Information System technics were used to delineate and identify land uses in the catchments. Specific algorithms were created to quantify the main pressures from land uses in the catchment and hydro-morphological alterations in the immediate basin. The values of the estimated pressure levels were correlated with ecological status indicators using metrics developed for the European Water Framework Directive. Data were obtained from European and River Basin Authorities databases. Results showed statistically significant correlations between the pressure levels quantified by the LUPLES method and the impact level detected by biological, physical and chemical metrics. This method provides a useful approach to estimate the pressure levels affecting lentic waterbodies and could be applied to approach how they could affect their ecological status.
de Yasmina Djitli, Dani Boix, Amel Milla, Faïza Marniche, Irene Tornero, David Cunillera-Montcusí, Jordi Sala, Stéphanie Gascón, Xavier D. Quintana, Samia Daoudi-Hacini
In Limnetica, 40(2) (February, 2021), 000–000
de Lasad Chiheb, Bensaci Ettayib, Nouidjem Yassine, Hadjab Ramzi
In Journal of Bioresource Management, 8(1) (2021), 2
En ligne : corescholar.libraries.wright.edu[...]
The spatial and temporal variation patterns of birds were investigated in the Oasis ecosystem of the North of Algeria Sahara. This contribution aimed to investigate the poorly studied bird fauna of Bousaâda oasis. The direct observation method was used for bird counts, adopted only during the breeding period. A total of 53 species of birds from 29 families and 16 orders were assessed in the different habitats of the Oasis (palm, fruit trees and, cultivated crops). The Passeriformes order was the most abundant represented by 35 species and 16 families. The relative abundance and species richness were recorded during our study period over different seasons and thought that whole surveyed stations represent all the oasis habitats. The Boussaâda oasis holds 18 resident-breeder species and is a transit zone for many migratory birds 14 and 10 species for summer and winter migrants respectively) and11 occasional visitor ones. These results confirmed the positive effects of stations and seasons on the richness and abundance of birds of Bousaâda oasis.
de Marie Suet, Juan Guillermo Lozano‐Arango, Pierre Defos du Rau, Clemence Deschamps, Mohammed Adam Abdalgader Mohammed, Elfirdous Elbashary Adam, Eltayeb Mohammed Eldegair, Mohamed Elmekki Ali Elbadawi, Ibrahim Mohammed Hashim, Noman Kirrem Kpoore, et al.
In Ibis, 163(2) (January, 2021), 16
En ligne : onlinelibrary.wiley.com[...]
In several regions of the world, the remoteness of potential bird hotspots and lack of trained observers have often prevented countries from effectively designing proper monitoring schemes at a national scale. For many countries, it is not known whether certain bird strongholds have been missed that should be included for more complete censuses. Such gaps at national scales, sometimes large, may be detrimental for global monitoring schemes. To address this, we used the irregular participation of Sudan to the International Waterbird Census (IWC) as a case study. We designed and tested a method based on remote-sensing data of the country’s lowlands to detect open water bodies in order to develop predictive models of the potential distribution of waterbird abundance and diversity. To identify open water bodies and their flooding duration, we used a Modified Normalized Difference Water Index (MNDWI) derived from Landsat 8 data. Field ornithological surveys were then used as ground-truth data to estimate the method’s accuracy. The statistical results (overall accuracy = 0.972; Kappa index = 0.93) confirmed its effectiveness. Remotely sensed water bodies and additional environmental covariates were then used to build simple habitat models of the distribution of waterbird abundance and diversity based on IWC field survey data. Of the 3119 remotely sensed clusters of open water bodies, three were predicted to host more than 10 000 waterbirds, 89 more than 1000 waterbirds and five more than 30 waterbird species. Located mainly in the southern agricultural floodplains along the main rivers, these predicted waterbird strongholds are therefore recommended for inclusion in the next IWC survey in Sudan. Our findings indicate that using remote sensing to identify open water bodies combined with simple statistical modelling is likely to be a cost-effective solution to improve IWC sampling and to enhance both waterbird and wetland monitoring in vast under-surveyed regions.Avifauna diversity and phenology in a Ramsar site: Lake Tonga (Northeastern Algeria) (2021)
de A. Gherib, A. Lazli, S. Naili, A. Boucheker, D. Ikhlef, N. I. Mechaka
2021, 321–344
En ligne : amz.museucienciesjournals.cat[...]
Between 2013 and 2016 we conducted an inventory and characterization of aquatic avifauna at Lake Tonga, a Ramsar site. We identified 61 species belonging to 17 families, dominated by Anatidae with 14 species. The inventoried species have different phenological status. Some are known for their regular wintering and some for their summer concentrations, while others are residents year round. Population analysis showed the presence of endangered species such as Oxyura leucocephala, Marmaronetta angustirostris and Aythya nyroca, that are protected by national and/or international laws. Bird counts showed monthly variations in total abundance and richness, peaking during winter. Peak numbers were recorded in February and January, reflecting gatherings to prepare for prenuptial migration. Analysis of diversity and equitability indices indicated that maximum values were generally recorded during the pre– and post–nuptial passages (H'= 3.51 and E = 0.72). Our results reflect the importance of this wetland as a wintering site and nesting site for numerous waterbirds species.
de Nigel G. Taylor, Patrick Grillas, Hazem Al Hreisha, Özge Balkız, Maud Borie, Olivier Boutron, Ana Catita, Jocelyn Champagnon, Semia Cherif, Kerim Cicek, et al.
In Regional Environmental Change, Online (2021), 25
Wetlands are critically important for biodiversity and human wellbeing, but face a range of challenges. This is especially true in the Mediterranean region, where wetlands support endemic and threatened species and remain integral to human societies, but have been severely degraded in recent decades. Here, in order to raise awareness of future challenges and opportunities for Mediterranean wetlands, and to inform proactive research and management, we identified (a) 50 key issues that might affect Mediterranean wetlands between 2020 and 2050, and (b) 50 important research questions that, if answered, would have the greatest impact on the conservation of Mediterranean wetlands between 2020 and 2050. We gathered ideas through an online survey and review of recent literature. A diverse assessment panel prioritised ideas through an iterative, anonymised, Delphi-like process of scoring, voting and discussion. The prioritised issues included some that are already well known but likely to have a large impact on Mediterranean wetlands in the next 30 years (e.g. the accumulation of dams and reservoirs, plastic pollution and weak governance), and some that are currently overlooked in the context of Mediterranean wetlands (e.g. increasing desalination capacity and development of antimicrobial resistance). Questions largely focused on how best to carry out conservation interventions, or understanding the impacts of threats to inform conservation decision-making. This analysis will support research, policy and practice related to environmental conservation and sustainable development in the Mediterranean, and provides a model for similar analyses elsewhere in the world.
de Alessandro Ferrarini, Claudio Celada, Marco Gustin
In Science of The Total Environment, 751 (01/2021), 141556
En ligne : linkinghub.elsevier.com[...]
Wetlands provide a wide range of ecosystem services, including supplying the food and shelter for a rich assemblage of waterbirds and providing the stopover sites that allow birds to make migratory journeys. Human impact and the ongoing climate change are however reducing the ability of wetlands to provide such important services. Through field surveys, GIS analyses and climate projections, we assessed the status of, and threats to, 38 largest wetlands belonging to the Mediterranean bird flyways in Sardinia and Sicily (Italy). We then combined ten decision criteria about avifaunal diversity and human/climate threats in order to prioritize the studied wetlands from most to least worthy of urgent interventions.
de Said El Falah, Ismail Mansouri, Wafae Squalli, Driss Ousaaid, Abdelbari El Agy, Mohamed Dakki
In Journal of Animal Behaviour and Biometeorology, 9(1) (2021), -----
En ligne : www.jabbnet.com[...]Etat des lieux des zones humides algeriennes: typologie et inventaire
de Aïda Saïfouni, Mohammed Bellatreche
In Algerian journal of arid environment, 10(2) (Decembre 2020), 20
Our study relates to an inventory of wetlands in Algeria, with the proposal of a new typology of wet habitats. The aim is to standardize the information base relating to Algerian wetlands, on the one hand, and to establish a classification of all wetlands in the country, on the other. The method adopted is a national inventory of wetlands carried out between 2018 and 2019, which reported 5404 wetlands, among which, 4252 natural and 1152 artificial. Numerically, the ecological region of the North East occupies the first place with 1585 wets sites, followed by the Nord-Center region (1479 sites), the High-Plateau region (1095 sites), the South region (660 sites), and finally, we find the North West region with 585 wetlands. The new classification system for the main wetland habitats is divided into two categories: “coastal” marine wetlands and “terrestrial” continental wetlands. The new typology adopted has made it possible to identify 71 habitats at the national level, including 46 continental habitats and 25 "coastal" marine habitats. Finally, our study represents a working tool both for scientists and for planners and managers, concerned with the sustainable use of the country's wetlands.
de Elie Gaget, Vincent Devictor, Bernard Frochot, Régis Desbrosses, Marie-Christine Eybert, Bruno Faivre
In Journal of Biogeography, Online (December, 2020)
En ligne : onlinelibrary.wiley.com[...]
This study investigates whether, and how, the composition of riparian bird communities has been affected by climate warming and habitat change. Although these two forces act separately, their respective contributions are rarely examined. Moreover, while the response of a given community may be a function of latitude and altitude, most studies have focused on these gradients separately. Riparian ecosystems are an opportunity to investigate community change along latitudinal and elevational gradients. Location France, three major rivers (the Doubs, the Allier and the Loire) Taxon Birds. Methods Drawing upon bird community monitoring data over a period of 31 years (1982–2013, n = 1,286 point counts), we assessed community adjustment to temperature increase with the Community Temperature Index (CTI), and the homogenization pattern following habitat conversion with the Community Specialization Index (CSI). We evaluated the spatial climatic debt accumulated by communities, and the interaction between CTI and CSI trends. Furthermore, we tested differences in trends for lowland and highland elevations. Results Over the study period, the temperature increased by 1.17°C, and the CTI by 0.12°C, which corresponds to a spatial climatic debt of 4.9 km/year. Lowland communities adjusted to warming but not highland communities, which have experienced a decline in species abundance. CSI trends revealed biotic homogenization in both lowland and highland communities. This finding was uncorrelated with the CTI increase, and is thought to be due to the pressure from land use change on community composition. Main conclusions Riparian breeding bird communities have been affected by a temperature increase and, potentially, habitat change. Highland communities are most vulnerable to climate warming. Both climate warming and habitat change appear to have rapidly affected the composition of local communities, with expectable concerns on their diversity and specificity in the long term.
de Brigitte Poulin
In La Cistude, 132 (Décembre 2020), 24-27
En ligne : fr.calameo.com[...]Ecosystem services in salt lakes: An ethnobotanic case study of halophytes from Algeria
de Fatma Demnati, Zoubir Boubaker, Farid Allache, Lisa Ernoul
In Ecologia Mediterranea, 46(2) (December, 2020), 1-12
Ecosystem services are well recognized in wet- lands; however, less attention is given to the ser- vices provided in salty wetland habitats. There are numerous salt lakes of international importance located in the northern Sahara region of Algeria. An ethnobotanical survey was conducted among the local population surrounding Chott Merouane. This survey was implemented to determine plant diversity and possible ecosystem services and improve conservation in these sen- sitive wetland habitats. Chott Merouane is a Ramsar site located in the southeast of Algeria in the Mediterranean bioclimatic Sahara. Based on a literature review of halophytic plants in the study area. The botanical inventory identified 22 plant species belonging to 20 genera and 16 families. Amongst these plants, Amaranthaceae, Zygophyllaceae, Nitrariaceae and Asteraceae dominated. A total of 48 participants were randomly selected and interviewed from three villages. The semi-directed interviews revealed that 77% of the plant species were used for traditional medicine, 65% for fodder, 41% for wood-fuel, 14% for crafts and 5% for food and other uses. The three endemic species iden- tified (Tetraena geslinii (Coss.) Beier & Thulin, Limoniastrum guyonianum Boiss. and Euphorbia guyoniana Boiss. & Reut.) had the highest values of relative frequency of citation and use value. Local knowledge was unevenly distributed and showed significant differences by gender and education level. This study highlights the importance of provi- sioning and cultural ecosystem values attributed to plants in salty wetlands and demonstrates the importance of ethno-botanical studies as a basic tool to contribute to the management and conservation of wetland plant resources in salty wetland environments./
Les services écosystémiques des zones humides sont bien reconnus, cependant, moins d’at- tention est accordée aux services fournis par les zones humides salées. Il existe de nombreux lacs salés d’importance internationale situés dans la région nord du Sahara, en Algérie. Une enquête ethnobotanique a été menée auprès de la population locale autour du Chott Merouane. Cette enquête a été mise en œuvre pour déterminer la diversité végétale et les services écosystémiques possibles et améliorer la conservation dans ces habitats humides sen- sibles. Le Chott Merouane est un site Ramsar situé au sud-est d’Algérie dans l’étage biocli- matique méditerranéen saharien. En se basant sur une revue de la littérature sur les plantes halophytes dans la zone d’étude. L’inventaire botanique a identifié 22 espèces végétales appartenant à 20 genres et 16 familles. Parmi ces plantes, les Amaranthaceae, Zygophyllaceae, Nitrariaceae et Asteraceae dominaient. Un total de 48 participants a été sélectionné au hasard et interrogés dans trois villages. Les entretiens semi-dirigés ont révélé que 77 % des espèces végétales étaient utilisées pour la médecine tra- ditionnelle, 65 % pour le fourrage, 41 % pour le bois de chauffage, 14 % pour l’artisanat et 5 % pour l’alimentation et d’autres usages. Les trois espèces endémiques identifiées (Tetraena geslinii (Coss.) Beier & Thulin, Limoniastrum guyonianum Boiss. et Euphorbia guyoniana Boiss. & Reut.) sont les plus citées avec les plus fortes valeurs d’utilisation. Les connaissances locales sont inégalement réparties et présentent des différences importantes selon le sexe et le niveau d’éducation. Cette étude souligne l’importance de la valeur des services écosystémiques et culturels attribuée aux plantes dans les zones humides salées et démontre l’importance des études ethnobota- niques comme outil de base pour contribuer à la gestion et à la conservation des ressources végétales dans les zones humides salées.
de Chabou Sarra, Khammar Hichem, Hadjab Ramzi, Saheb Menouar
In Ecology, Environment and Conservation, 26(4) (December, 2020), 15
En ligne : www.researchgate.net[...]
This study was carried out in the north-eastern part of Algeria on two wetlands, one artificial (Beni Haroun Dam) and the other natural (Redjla Marsh) from November 2017 to October 2018. Forty seven species from 16 families and 9 orders and four guilds have been identified. The richest family in species and abundance is the Anatidae family (11 species at the Beni Haroun Dam and 12 species at the Redjla Marsh). From an effective point of view, the Great Cormorant Phalacrocorax carbo (Phalacrocoracidae) is the species most represented in the Beni Haroun Dam and the Macroule Coot Fulica atra (Rallidae) is the most represented in Redjla Marsh. Some species frequenting these environments have a national conservation status such as the Great Cormorant Phalacrocorax carbo, the Marbled Teal Marmaronetta angustirostris and the White Spoonbill Platalea leucorodia. Some species are classified as threatened and vulnerable on the IUCN Red List, such as the Marbled Teal and the Ferruginous Duck Aythia nyroca.Perception of climate change and mitigation strategies in two European Mediterranean deltas
de Lisa Ernoul, Stella Vareltzidou, Mathilde Charpentier, Camille Muryanyi-Kovacs
In AIMS Geosciences, 6(4) (December, 2020), 561-576
En ligne : www.aimspress.com[...]
Acceptance of mitigation and adaptation strategies is related more to the perceived levels of threats as opposed to real risks. Understanding public perception of climate change is crucial for the implementation of appropriate and effective actions. This study analyzed the perceptions of climate and global changes in two European Mediterranean deltas in order to determine the similarities and differences at a regional scale and to apprehend potential adaptation and mitigation strategies necessary for the future. A total of 395 participants responded to a questionnaire through person to person interviews. Survey analysis was conducted through a multi-method approach using standard descriptive statistics and qualitative data analysis. The majority of participants in both deltas expressed that climate change was a serious problem and that human activity was a contributing factor. Despite the recognition of the importance of climate change, little action was being taken to adapt or mitigate these changes. Our results suggest that a site specific approach using confirmed information sources with adapted communication techniques is necessary to be more effective and to spur changes in practice at a local scale.
de Bia A. Almeida, Esther Sebastián‐González, Luiz Dos Anjos, Andy J. Green
In Freshwater Biology, 65(12) (December, 2020)
En ligne : onlinelibrary.wiley.com[...]
The restoration of degraded areas and the creation of artificial ecosystems have partially compensated for the continuing loss of natural wetlands. However, the success of these wetlands in terms of the capacity of supporting biodiversity and ecosystem functions is unclear. Research is needed to improve our understanding of the value of restored and constructed wetlands for functional diversity of freshwater fauna. We compared natural, restored, and artificially created wetlands present within the Doñana Natural Space, Spain and valued as important for waterbirds. We evaluated if these wetlands are equivalent in terms of waterbird functional trait diversity and composition, during both the wintering and breeding seasons. We modelled functional diversity measures and functional group species richness describing species diet, body mass, and foraging techniques with generalised linear mixed models in 20 wetlands monitored between 2006 and 2011. We used three different statistical approaches to evaluate the robustness of our results. Artificial wetlands constructed for conservation failed to reach the functional diversity of natural and restored wetlands. Unexpectedly, artificial ponds constructed for fish production performed better, and even exceeded natural wetlands for functional richness during winter. Fish ponds stood out as having a unique functional composition, connected with increase in richness of opportunistic gulls and decrease of species sensitive to high salinity. Overall, the functional structure of breeding communities was more affected by wetland type than wintering communities. Our findings suggest that compensating the loss of natural wetlands with restored and artificial wetlands results in systems with altered waterbird-supported functions, such as seed dispersal or nutrient cycling. Protection of natural Mediterranean wetlands is vital to maintain the original diversity and composition of waterbird functional traits. Furthermore, restoration must be prioritised over the creation of artificial wetlands, which, even when intended for conservation, may not provide an adequate replacement.Towards a Universal Declaration of the Rights of Wetlands
de G. T. Davies, C. M. Finlayson, D. E. Pritchard, N. C. Davidson, R. C. Gardner, W. R. Moomaw, E. Okuno, J. C. Whitacre
In Marine and Freshwater Research, 72(5) (November, 2020)
En ligne : www.publish.csiro.au[...]
The rights of Nature, a concept recognised by several courts, legislatures and international governance institutions, is being promoted by some non-governmental organisations, scientists, attorneys, Indigenous peoples, local communities, and others. In this article we propose a Universal Declaration of the Rights of Wetlands, consistent with the 1982 World Charter for Nature. Recognition of these rights supports the provision of ecosystem services essential to human well-being and to other life on Earth. Further, such rights could reinforce efforts to reduce wetland loss and deterioration, thereby slowing climate destabilisation and biodiversity declines. Because world scientists have warned that biodiversity loss, ecosystem degradation and climate destabilisation, which intensify wetland loss, constitute global emergencies, new approaches are required to ensure that wetlands are protected and their benefits to people sustained. The proposed Universal Declaration of the Rights of Wetlands states that wetlands possess rights to: exist; their ecologically determined location in the landscape; natural, connected and sustainable hydrological regimes; ecologically sustainable climatic conditions; naturally occurring biodiversity; regeneration and restoration; integrity of structure, function and evolutionary processes; fulfil natural ecological roles in the Earth’s processes; and be free from pollution and degradation. Recognition of these rights is seen as an essential step in efforts to stop wetland loss and deterioration.
de Mark A.F. Gillingham, Fabrizio Borghesi, B. Karina Montero, Francesca Migani, Arnaud Béchet, Manuel Rendón-Martos, Juan A. Amat, Enrico Dinelli, Simone Sommer
In Science of The Total Environment, Online (11/2020), 143250
En ligne : linkinghub.elsevier.com[...]
Elevated concentrations of trace elements represent a major concern to wetland ecosystems, since river estuaries are geochemical endpoints that accumulate pollution. Although the negative impact of environmental exposure of highly toxic elements such as Pb and Hg has received substantial attention, we still lack a comprehensive understanding of the effects that these and other common trace elements have on natural populations. We used greater flamingos as a study system within three sites that represent a gradient of pollution. Controlling for environmental sediment exposure, we assessed if signatures of bioaccumulation in feathers for ten trace elements (As, Cd, Cr, Cu, Hg, Ni, Pb, Se, Sn and Zn) are associated with two known proxies of health: body condition and the gut bacterial microbiome. We found evidence of an adverse effect of Se, Hg, and Pb bioaccumulation on body condition. Furthermore, bioaccumulation of the elements As, Cu, Se, Pb and Zn influenced different aspects of the gut microbiome. Bioaccumulation of Se led to a shift in the microbiome composition, largely driven by an enrichment of Bacteroides plebeius, which is linked to the breakdown of sulphated polysaccharides of algae. Bacteroides plebeius was negatively associated with chick body condition, suggesting an adverse effect of a microalgae diet rich in Se. Pb bioaccumulation was linked with a decrease in microbial diversity (adjusted-R2 = 10.4%) and an increase in heterogeneity of the microbial community (adjusted-R2 = 10.5%), an indication of impaired gut homeostasis. As, Cu and Zn had more nuanced effects on gut microbiome heterogeneity according to breeding site and bioaccumulation concentration. Our results therefore suggest that in addition to well-studied elements, bioaccumulation of poorly studied elements also adversely affect health of natural populations.Rivers’ natural reservoirs: new inputs to the classification of Mediterranean and Saharan wetlands
de Mohamed Dakki, Bouchta El FEllah, Abdeljebbar Qninba
In Bulletin de l'Institut Scientifique (Rabat), 42 (2020)
This article is dedicated to natural reservoirs, widely distributed ecosystems in North Africa but poorly studied. Their hydrological and ecological characteristics are insufficiently highlighted in existing wetland typologies; that’s why we recommend to assign them to new wetlands’ types. Generally named gueltas, these reservoirs have a common genesis model, based on natural dams that block river beds. Four types of gueltas are identified: (1) landslide lakes, mountainous reservoirs created upstream of voluminous landslides that block deep valleys; (2) river gueltas, river beds blocked by small deposit thresholds, generally installed by tributaries; (3) dune gueltas, generated upstream to active Saharan dunes; (4) estuarine gueltas, due to fluviomarine dikes transforming estuaries into large ‘saltwater ponds’. These standing waters are built in river beds, and their characteristics and communities are highly fashioned by floods, both in their composition and functioning. The river gueltas are widely distributed in North Africa, while other reservoirs are poorly represented, some of them being threatened. Permanent reservoirs, in both mountains and desert, host endemic fishes, while river gueltas are conservatories of fish during dry seasons. Considering these originalities and values, several Moroccan gueltas have been classified in Ramsar sites, hoping they would benefit from future studies.
Lestes macrostigma (Eversmann), the Dark Spreadwing
de David Chelmick, Philippe Lambret
In Journal of the British Dragonfly Society, 36(2) (November, 2020), 84-108
Lestes macrostigma (Dark Spreadwing) occurs across the southern Palearctic from the Atlantic coast as far east as Mongolia. It is locally common in the central part of its range, including Greece and Bulgaria, but becomes increasingly rare in the western parts of the region where, with notable exceptions, it is essentially coastal. It is very much associated with temporary, brackish and and saline habitats and, very often, with Bolboschoenus maritimus (Sea Club Rush). Many of its coastal habitats are under threat, especially from wetland transformation schemes of various types and, for tnat reason, the species is listed as Endangered in the European Red list.Integrating wetland bird point count data from humans and acoustic recorders
de Laura Stewart, Douglas Tozer, Janine McManus, Lucas Berrigan, Kiel Drake
In Avian Conservation and Ecology, 15(2) (2020/10/08)
En ligne : www.ace-eco.org[...]
Stewart, L. N., D. C. Tozer, J. M. McManus, L. E. Berrigan, and K. L. Drake. 2020. Integrating wetland bird point count data from humans and acoustic recorders. Avian Conservation and Ecology 15(2):9. https://doi.org/10.5751/ACE-01661-150209Ecology of avian settlements in Lake Tonga (Northeast Algeria)
de K. Loucif, M. Bara, A. Grira, M. C. Maazi, A. Hamli, M. Houhamdi
In Zoodiversity, 54(4) (September, 2020), 275-284
En ligne : ojs.akademperiodyka.org.ua[...]
Lake Tonga is an integral reserve within the El-Kala National Park, Biosphere Reserve and Ramsar site. This study consists in determining the diversity and phenology status of waterbirds in this reserve over an entire annual cycle (2017–2018). The census was carried out from fixed observation points. Of the 35 species recorded, wintering birds dominate with 12 species (34 %), followed by breeding sedentary species with 11 species (32 %). The breeding water bird populations are dominated by the common coot Fulica atra, (with a maximum of 6,033 birds) followed by the Anatidae, Herons and Grebes. Lake Tonga is a breeding area for several avian species and a recruitment site for a multitude species bird during the wintering period. Three Anatidae nest at Lake Tonga: the white-headed duck Oxyura leucocephala, the ferruginous duck Aythya nyroca and the mallard Anas platyrhynchos.
de Kathrin Weise, Rene Höfer, Jonas Franke, Anis Guelmami, Will Simonson, Javier Muro, Brian O’Connor, Adrian Strauch, Stephan Flink, Jonas Eberle, et al.
In Remote Sensing of Environment, 247 (September, 2020), 111892
En ligne : www.sciencedirect.com[...]
Wetlands are the most fragile and threatened ecosystems worldwide, and also one of the most rapidly declining. At the same time wetlands are typically biodiversity hotspots and provide a range of valuable ecosystem services, such as water supply and purification, disaster risk reduction, climate change adaptation, and carbon sequestration. Pressures on wetlands are likely to further intensify in the coming decades due to increased global demand for land and water, and due to climate change. Stakeholders at all levels of governance have to be involved to slow, stop and reverse these processes. However, the information they need on wetland extent, their ecological character, and their ecosystem services is often scattered, sparse and difficult to find and access. The freely available Sentinel satellite data of the Copernicus Programme, as well as the Landsat archive, provide a comprehensive basis to map and inventory wetland areas (extent), to derive information on the ecological status, as well as long- and short-term trends in wetland characteristics. However, making use of these Earth Observation (EO) resources for robust and standardized wetland monitoring requires expert knowledge on often complex data processing techniques, which impedes practical implementation. In this respect, the Satellite-based Wetland Observation Service (SWOS), a Horizon 2020 funded project (www.swos-service.eu) has developed and made disseminated monitoring approaches based on EO data, specifically designed for less experienced satellite data users. The SWOS monitoring tools aim at assisting countries in conducting national wetland inventories for their Sustainable Development Goals (SDG) reporting and monitoring obligations, and additionally facilitates other monitoring obligations such as those required by the Ramsar Convention and supports decision-making in local conservation activities. The four main components of the SWOS approach are: map and indicator production; software development; capacity building; and initializing the GEO Wetlands Community Portal. Wetland managers and data analysists from more than fifty wetland sites and river basins across Europe, the Middle East, and Africa investigated the benefits and limitations of this EO-based wetland mapping and monitoring approach. We describe research that applies the SWOS tools to test their potential for the mapping of wetlands in a case study based in Albania, and show its effectiveness to derive metrics relevant to the monitoring of SDG indicator 6.6.1.Multitemporal optical and radar metrics for wetland mapping at national level in Albania
de Javier Muro, Ana Varea, Adrian Strauch, Anis Guelmami, Eleni Fitoka, Frank Thonfeld, Bernd Diekkrüger, Björn Waske
In Heliyon, 6(8) (August, 2020), e04496
En ligne : linkinghub.elsevier.com[...]
Wetlands are highly dynamic, with many natural and anthropogenic drivers causing seasonal, periodic or permanent changes in their structure and composition. Thus, it is necessary to use time series of images for accurate classifications and monitoring. We used all available Sentinel-1 and Sentinel-2 images to produce a national wetlands map for Albania. We derived different indices and temporal metrics and investigated their impacts and synergies in terms of mapping accuracy. Best results were achieved when combining Sentinel-1 with Sentinel-2 and its derived indices. We reduced systematic errors and increased the thematic resolution using morphometric characteristics and knowledge-based rules, achieving an overall accuracy of 82%. Results were also validated against field inventories. This methodology can be reproducible to other countries and can be made operational for an integrated planning that considers the food, water, and energy nexus.
de Elie Gaget, Thomas Galewski, Frédéric Jiguet, Anis Guelmami, Christian Perennou, Coralie Beltrame, Isabelle Le Viol
In Conservation Biology, 34(4) (August, 2020)
En ligne : conbio.onlinelibrary.wiley.com[...]
While the impacts of climate and land use changes on biodiversity have been widely documented, their joint effects remain poorly understood. We evaluated how non-breeding waterbird communities adjust to climate warming along a gradient of land use change. Using mid-winter waterbird counts (132 species) at 164 major non-breeding sites in 22 Mediterranean countries, we assessed the changes in species composition during 1991–2010, regarding thermal niche position and breadth, in response to regional and local winter temperature anomalies and to natural habitat conversion. We showed that in response to the temperature increase, communities became relatively richer in warm-dwelling species, but less where natural habitat conversion occurred. At the sites affected by natural habitat conversion, the overall species richness decreased with time, while the abundance relatively increased for the species with a broader thermal niche, independently of their thermal affinities. The strong negative relationship between natural habitat conversion and community adjustment to temperature increases suggests an antagonistic interaction between climate warming and habitat change. Indeed, we found no evidence of community adjustment to climate warming when natural habitat conversion was higher than 5% over 15 years. These results underline the importance of habitat conservation in community adjustment to climate warming. Article impact statement: Waterbird communities do not adjustment to climate warming when natural habitat conversion is >5% over 15 years. This article is protected by copyright. All rights reservedSolution locale contre menace globale ?
de Elie Gaget, Thomas Galewski
In Espaces naturels, 71 (Juillet-Septembre 2020), 46-47Interdiction du plomb de chasse, une difficile mise en oeuvre
de Jean-Yves Mondain-Monval, Anthony Olivier, Olivier Cardoso
In Espaces naturels, 71 (Juillet-Septembre 2020), 36-37
de Bigna L. Steiner, Natàlia Alonso, Patrick Grillas, Christophe Jorda, Gaël Piquès, Margaux Tillier, Núria Rovira
In PLOS ONE, 15(6) (18 juin 2020), e0234853
En ligne : journals.plos.org[...]
A new method to evaluate archaeological wetland sites in a more objective way was tested. Different wetland environments have been sampled in areas of a nature reserve and their macroremain content analysed to build a modern analogue dataset. This dataset was then used to characterise archaeological samples from a navigation channel from the Roman port city Lattara. In the modern analogue samples, the different wetland types (saline/brackish or fresh water) could be differentiated in the correspondence analysis. Within these groups, the sampled area of the littoral (submerged, shoreline, unsubmerged) could also be differentiated. This dataset can therefore provide a basis for the interpretation of the nature and degree of aquatic influence and layer formation processes in archaeobotanical records of coastal sites. In the tested archaeological samples from the navigation channel of Lattara, changes in space and time could be tracked using the modern analogue dataset and geoarchaeological information. The channel lost its fresh water supply and silted up over a short period of time (approx. 100 years).Mediterranean wetland conservation in the context of climate and land cover change
de Roxanne Leberger, Ilse R. Geijzendorffer, Elie Gaget, Anis Guelmami, Thomas Galewski, Henrique M. Pereira, Carlos A. Guerra
In Regional Environmental Change, 20(2) (6/2020), 67
En ligne : link.springer.com[...]
Wetlands are known to support diverse and unique species assemblages. Globally, but particularly in the Mediterranean basin, they are threatened by climate change and natural habitat loss. Despite an alarming decline of wetlands over the last century, standardised and systematic site assessments at large scale do not exist. Here, we perform an integrated assessment of Mediterranean wetlands by evaluating the combination of wetland protection and anthropogenic pressures, namely climate and land cover change, and the subsequent impact on wintering waterbirds. We used a multivariate partial triadic analysis to quantify climate and land cover change for each site between 1990 and 2005. We found that wetland sites in the southeast of the Mediterranean basin combined low or no protection cover with the highest increases in temperature and losses in natural habitats. Despite these findings, these sites also lack observation data on biodiversity, which may underestimate the resulting impacts. However, there are examples where active conservation measurements contributed positively to slow down wetlands’ reduction. Biodiversity data coverage needs to be ensured, regularly updated, and extended across sites regardless of their protection level, to allow for the assessment of biodiversity trends. This should be further extended to include current investments in remote sensing approaches.Scientists’ warning to humanity on the freshwater biodiversity crisis
de James S. Albert, Georgia Destouni, Scott M. Duke-Sylvester, Anne E. Magurran, Thierry Oberdorff, Roberto E. Reis, Kirk O. Winemiller, William J. Ripple
In AMBIO, Online (June, 2020)
En ligne : link.springer.com[...]
Freshwater ecosystems provide irreplaceable services for both nature and society. The quality and quantity of freshwater affect biogeochemical processes and ecological dynamics that determine biodiversity, ecosystem productivity, and human health and welfare at local, regional and global scales. Freshwater ecosystems and their associated riparian habitats are amongst the most biologically diverse on Earth, and have inestimable economic, health, cultural, scientific and educational values. Yet human impacts to lakes, rivers, streams, wetlands and groundwater are dramatically reducing biodiversity and robbing critical natural resources and services from current and future generations. Freshwater biodiversity is declining rapidly on every continent and in every major river basin on Earth, and this degradation is occurring more rapidly than in terrestrial ecosystems. Currently, about one third of all global freshwater discharges pass through human agricultural, industrial or urban infrastructure. About one fifth of the Earth’s arable land is now already equipped for irrigation, including all the most productive lands, and this proportion is projected to surpass one third by midcentury to feed the rapidly expanding populations of humans and commensal species, especially poultry and ruminant livestock. Less than one fifth of the world’s preindustrial freshwater wetlands remain, and this proportion is projected to decline to under one tenth by midcentury, with imminent threats from water transfer megaprojects in Brazil and India, and coastal wetland drainage megaprojects in China. The Living Planet Index for freshwater vertebrate populations has declined to just one third that of 1970, and is projected to sink below one fifth by midcentury. A linear model of global economic expansion yields the chilling prediction that human utilization of critical freshwater resources will approach one half of the Earth’s total capacity by midcentury. Although the magnitude and growth of the human freshwater footprint are greater than is generally understood by policy makers, the news media, or the general public, slowing and reversing dramatic losses of freshwater species and ecosystems is still possible. We recommend a set of urgent policy actions that promote clean water, conserve watershed services, and restore freshwater ecosystems and their vital services. Effective management of freshwater resources and ecosystems must be ranked amongst humanity’s highest priorities.Biodiversity and phenological status of the waterbirds of the Lac des Oiseaux (Northeast of Algeria)
de F. Z. Boubekeur, S. Setbel, S. Atoussi, M. Bara, L. Bouaguel, I. Houhamdi, A. Kerfouf, M. Houhamdi
In Ukrainian Journal of Ecology, 10(5) (2020), 69–75
Counts carried out over two consecutive years (from September 2017 to August 2019) of waterbirds occupying the Lac des Oiseaux
(Ramsar site, wilaya of El-Tarf, extreme north-eastern Algeria) showed a species richness estimated at 38 waterbird species
belonging to 11 families. The Anatidae and Scolopacidae with 10 and 7 species respectively are the most families represented. The
former are mainly observed during the wintering season and the latter during the summer period. From an effective point of view,
Anatidae and Rallidae, mainly the Eurasian Coot Fulica atra are the most abundant. From a phenological point of view, eleven
species are summering, ten are resident and wintering and eight are sporadic species.
Bending the Curve of Global Freshwater Biodiversity Loss: An Emergency Recovery Plan
de David Tickner, Jeffrey J Opperman, Robin Abell, Mike Acreman, Angela H Arthington, Stuart E Bunn, Steven J Cooke, James Dalton, Will Darwall, Gavin Edwards, et al.
In BioScience, 70(4) (April, 2020), 330-342
En ligne : doi.org[...]
Despite their limited spatial extent, freshwater ecosystems host remarkable biodiversity, including one-third of all vertebrate species. This biodiversity is declining dramatically: Globally, wetlands are vanishing three times faster than forests, and freshwater vertebrate populations have fallen more than twice as steeply as terrestrial or marine populations. Threats to freshwater biodiversity are well documented but coordinated action to reverse the decline is lacking. We present an Emergency Recovery Plan to bend the curve of freshwater biodiversity loss. Priority actions include accelerating implementation of environmental flows; improving water quality; protecting and restoring critical habitats; managing the exploitation of freshwater ecosystem resources, especially species and riverine aggregates; preventing and controlling nonnative species invasions; and safeguarding and restoring river connectivity. We recommend adjustments to targets and indicators for the Convention on Biological Diversity and the Sustainable Development Goals and roles for national and international state and nonstate actors.
de Carsten A. Brühl, Laurence Després, Oliver Frör, Chandrashekhar D. Patil, Brigitte Poulin, Guillaume Tetreau, Stefanie Allgeier
In Science of The Total Environment, Online (April, 2020), 137800
En ligne : www.sciencedirect.com[...]
Bacillus thuringiensis subsp. israelensis (Bti) has been used in mosquito control programs to reduce nuisance in Europe for decades and is generally considered an environmentally-safe, effective and target-specific biocide. However, the use of Bti is not uncontroversial. Target mosquitoes and affected midges represent an important food source for many aquatic and terrestrial predators and reduction of their populations is likely to result in food-web effects at higher trophic levels. In the context of global biodiversity loss, this appears particularly critical since treated wetlands are often representing conservation areas. In this review, we address the current large-scale use of Bti for mosquito nuisance control in Europe, provide a description of its regulation followed by an overview of the available evidence on the parameters that are essential to evaluate Bti use in mosquito control. Bti accumulation and toxin persistence could result in a chronic expose of mosquito populations ultimately affecting their susceptibility, although observed increase in resistance to Bti in mosquito populations is low due to the four toxins involved. A careful independent monitoring of mosquito susceptibility, using sensitive bioassays, is mandatory to detect resistance development timely. Direct Bti effects were documented for non-target chironomids and other invertebrate groups and are discussed for amphibians. Field studies revealed contrasting results on possible impacts on chironomid abundances. Indirect, food-web effects were rarely studied in the environment. Depending on study design and duration, Bti effects on higher trophic levels were demonstrated or not. Further long-term field studies are needed, especially with observations of bird declines in Bti-treated wetland areas. Socio-economic relevance of mosquito control requires considering nuisance, vector-borne diseases and environmental effects jointly. Existing studies indicate that a majority of the population is concerned regarding potential environmental effects of Bti mosquito control and that they are willing to pay for alternative, more environment-friendly techniques.
de Antoine Gazaix, Mario Klesczewski, Michel-Ange Bouchet, Manuel Cartereau, James Molina, Henri Michaud, Serge D. Muller, Lionel Pirsoul, Perrine Gauthier, Patrick Grillas, et al.
In Botany Letters, 167(2) (April, 2020), 201-211
En ligne : doi.org[...]
Mediterranean temporary pools are threatened ecosystems that host a unique plant community, mostly composed of annual species with large and long-lived seed banks. The longevity of their seed bank, the scarcity of their habitat, the small size of their populations and the low frequency of above-ground vegetation result in a low probability of detection of these species. The discovery of new populations of such rare species are thus important for our understanding of the ecology of the temporary pool ecosystem. Lythrum thesioides M.Bieb., 1808 is a very rare annual species of temporary pools and river banks which was thought to be extinct in the South of France until 1998. Here, we review the distribution of the species and report the recent discovery of a population during a targeted search combining historical data on wetland occurrence on a particular geological substrate. We present new information on its autecology, pollen morphology and the karyotype. Only three populations are currently known worldwide for Lythrum thesioides, and only one of these has favorable management conditions. Thus, we outline new conservation perspectives in the context of a targeted search project and the conservation management of one population.
de Fritz Schiemer, Sajmir Beqiraj, Anton Drescher, Wolfram Graf, Gregory Egger, Franz Essl, Thomas Frank, Christoph Hauer, Severin Hohensinner, Aleko Miho, et al.
In Landscape Ecology, Online (March, 2020), 16
En ligne : link.springer.com[...]
Context Large near-natural rivers have become rare in Europe, a fact reflected in the high conservation status of many riverine ecosystems. While the Balkan still harbors several intact river corridors, most of these are under pressure from planned hydropower constructions. Unfortunately, there is little information available on the hydromorphodynamics and biota of Balkan rivers under threat.
de Juan Arizaga, Daniel Alonso, Arine Crespo, Xabier Esparza, Efrén Fernández, Iñigo López, David Martín, Antonio Vilches
In Avian Research, 11(1) (March, 2020), 29
En ligne : doi.org[...]
The dynamics and structure of many bird communities are changing due to the global warming and changes in the land use and management. The Ebro Valley constitutes one of the chief wintering areas for several passerine species in Iberia, and the reed beds spread across this Valley concentrate huge numbers of birds that use them to roost, while the surrounding agricultural areas serve as main foraging habitats. The aims of this work are (1) to quantify how variable a non-breeding passerine bird community associated to a reed bed area in the Ebro Valley is, and, (2) to test for the effect of weather on possible annual fluctuations in species’ proportions at a regional/local scale.
de Véronique Vassal, Luc Ector, Bart Van de Vijver, Vincent Roubeix, Anthony Olivier, Samuel Pauvert, Cédric Roy, Stéphanie Fayolle
In Botany Letters, Online (February, 2020)
En ligne : www.tandfonline.com[...]
Benthic diatoms are widely used as bio-indicators in water quality monitoring of rivers and streams, but less commonly in lentic waterbodies such as pools and lakes. Currently, a new method for assessing the ecological status of lakes is being tested in France to meet the requirements of the European Water Framework Directive (WFD) 2000/60/EC. This new method uses epilithic and epiphytic diatoms growing on stones and aquatic plants. Alternatively, freshwater turtles and the epizoic algae found on their carapaces may provide an excellent substrate for estimating water quality. Our study proposes an original diatom-based method for assessing the quality of water bodies in which turtles live. The main objective was to compare the Biological Diatom Index (BDI) values measured from epizoic diatom samples taken on the carapace of turtles with classical epilithic or epiphytic samples. Epizoic samples were taken from the carapaces of the turtle Emys orbicularis in two shallow French Mediterranean wetlands. Our results indicate that diatom assemblages differ slightly within the three substrates studied with limited variations in index value. However, some variability among epizoic samples from the same site suggests that several turtle individuals should be sampled for water quality biomonitoring.Perception et adaptation au changement climatique dans les deltas méditerranéens
de Lisa Ernoul, Camille Roumieux, Alain Sandoz
In Géoconfluences, Online (Janvier 2020), 5
En ligne : geoconfluences.ens-lyon.fr[...]
Les deltas méditerranéens sont des espaces dont les milieux dépendent des aménagements anthropiques des fleuves qui les alimentent. En tant que côtes basses à climat méditerranéen, ils sont particulièrement vulnérables aux effets probables des changements climatiques. L'étude de trois deltas (Rhône, Vardar et Gediz) montre que les pratiques de leurs habitants associent adaptation locale et prise de conscience globale, mais aucune adaptation efficace n'est possible sans gestion concertée à plusieurs échelles.Breeding ecology of the Cattle Egret (Bubulcus ibis) in Guerbes-Sanhadja wetlands of Algeria
de Sophia METALLAOUI, Hamdi Dziri, Abderazzak Bousseheba, Salim Heddam, Haroun Chenchouni
In Regional Studies in Marine Science, 33 (January, 2020), 100979
En ligne : www.sciencedirect.com[...]
Information about breeding ecology and nest site selection in the Cattle Egret (Bubulcus ibis) at newly established colonies are still lacking in many North African heronies. This study aimed at determining nest site selection and assessing breeding parameters of Cattle Egrets nesting, for the first time, at the Ouajaa marsh in Guerbes-Sanhadja wetlands (northern Algeria) in relation to nest site and nest traits. Breeding chronology of Cattle Egret in the region was monitored onsite, since the use of the wetland as a dormatory till the end of the breeding season. Egg morphometrics (length, breadth, weight and volume) and breeding parameters (clutch size, hatching, fledging and breeding successes) were measured and compared between nests built on different tree species (Salix alba and Acacia cyanophylla) and at different locations within crowns of nesting trees. The effects of nest site characteristics (nesting height, trees and positions) and nest traits (nest surface, outer and inner diameters) on breeding parameters were investigated using generalized linear models (GLMs). The breeding period of Cattle Egret at the Ouajaa Marsh lasted from 12th April to 20th July 2014. Egg morphometrics were similar between central and peripheral nests. Overall, Cattle Egret’s eggs measured 46.18 ± 2.03mm. Clutch size was on average 3.43 ± 0.91 eggs (N=53 nests). Overall, hatched eggs averaged 2.72 ± 0.91 per nest, whereas the number of fledglings totaled 134 chicks with an average 2.53 ± 0.85 per nest. The reproductive success at Guerbes-Sanhadja wetlands was 73.6%. However, it was higher (84%) in three-egg nests. GLMs showed that the number of hatchlings increased significantly with the increase of clutch size (P=0.032), and it was significantly higher (P=0.028) in central nests (2.74 ± 0.96 chicks) compared to peripheral nests (2.68 ± 0.82 chicks). GLM revealed that the number of hatchlings positively influenced the variation of the number of fledglings (P
de Etienne Fluet-Chouinard, Ben Stewart-Koster, Nick Davidson, C. Max Finlayson, Peter B. McIntyre
In Ecological Indicators, 109 (February, 2020), 105772
En ligne : www.sciencedirect.com[...]
Aquatic ecosystems are exposed to a host of anthropogenic stressors whose combined effect can be synthesized with cumulative stress indices. The reliability of cumulative stress indices depends primarily on: 1) stressor incidence maps derived from remote sensing or modeling but rarely validated against on-the-ground observations, and 2) the weighting scheme used to combine multiple stressors into a cumulative index typically based on expert opinion. In this paper, we evaluate the exposure and weights for 13 aquatic stressor maps of the world’s rivers with a comparison against local stress reporting across 1018 inland and coastal sites from the Ramsar Wetlands of International Importance. We found that globally-mapped and locally-reported stressors are poorly aligned overall (AUC-ROC = 0.50–0.63), and that concordance did not improve when stratifying by ecosystem types or continents. Agreement varied across individual stressors, was highest for hydrological stressors and lowest for habitat disconnectivity stressors. We estimated stressor weights from the comparison and found them to be remarkably aligned well with expert-generated weights, suggesting there is convergence on a stressor hierarchy across local and global scales. Our comparison illustrates the value of integrating data across scales to inform the calculation of global stressor indices. Continued systematic stressor monitoring across environmental observation networks is central to benchmarking maps of ecosystem stress globally.
de Ahlam Chettibi, Ettayib Bensaci, Fateh Mimeche, Soumia Djamai
In Studia Universitatis Babeş-Bolyai Biologia, 64(2) (December, 2019), 25-40
En ligne : www.studia.ubbcluj.ro[...]
The present study was aimed to determine the effect of some environmental factors such as water features and vegetation cover on the distribution and habitat use of herons over different seasons of the bird’s life (breeding, passage and wintering) in Tonga Lake (North East Algeria) from March 2017 to February 2018. We used remote sensing techniques to study the environmental factors variations, we adopted the normalized difference vegetation index (NDVI) to give an estimate of vegetation cover and we used the normalized difference water index (NDWI) to study the water features. In our study, we determine that the abundance and richness of herons species is largely influenced by the water features and vegetation cover. The seasonal variations in the amount of these environmental factors are known to affect the availability of various food items for herons. Eight species of herons were identified during the study period. Pearson’s Correlation Coefficient was used to examine the effect of NDVI and NDWI on the distribution of herons. The results showed that the NDVI was significantly positively correlated with richness and abundance of herons respectively (r=0.728, p
de N. C. Davidson, L. Dinesen, S. Fennessy, C. M. Finlayson, Patrick Grillas, A. Grobicki, R. J. McInnes, D. A. Stroud
In Marine and Freshwater Research, 71 (December, 2019), 10
En ligne : www.publish.csiro.au[...]
We review the mechanisms established by the Ramsar Convention for reporting on the status and change in the ecological character of wetlands. We assess the extent of their implementation and compliance, but not issues of the adequacy of their design nor the consequences of their extent of implementation. We conclude that, with the exception of qualitative national-scale reporting in triennial Contracting Party National Reports, there is inadequate implementation and compliance with most of these mechanisms, notably concerning required reporting under Article 3.2 of the Convention and the updating of the Information Sheet on Ramsar Wetlands (RIS). This limits the ability of the Convention to assess the status, and trends in status, of designated Wetlands of International Importance (Ramsar Sites), and to inform future decision-making and priority-setting for the wise use of all wetlands. As has been recognised by the Ramsar Convention, unless compliance with these mechanisms is improved, sufficient information will not be gathered through the mechanisms of Ramsar Convention to assess fully the Sustainable Development Goal 6.6.1 indicator supported by the Convention on change in the extent of water-related ecosystems over time.Trends in the ecological character of the world’s wetlands
de N. C. Davidson, L. Dinesen, S. Fennessy, C. M. Finlayson, Patrick Grillas, A. Grobicki, R. J. McInnes, D. A. Stroud
In Marine and Freshwater Research, 71 (December, 2019), 10
En ligne : www.publish.csiro.au[...]
We assessed trends in the ecological character of wetlands generally and of Ramsar Sites reported in 2011, 2014 and 2017 by the Contracting Parties to the Ramsar Convention on Wetlands in their national reports. There was more widespread deterioration than improvement in the ecological character of wetlands generally, with deterioration increasingly more widespread between 2011 and 2017. The ecological-character trends in Ramsar Sites were significantly better than those of wetlands generally, but an increasingly more widespread deterioration of ecological character was reported between 2011 and 2017. Trends in the ecological character of wetlands generally, and of Ramsar Sites were worst in Africa and Latin America and the Caribbean, and recently also in Oceania, and better in North America and Europe. Deterioration in the ecological character of Ramsar Site was more widespread in countries with a large average area of their Ramsar Sites. This information on trends of wetland ecological character can contribute to assessing the achievement of the 2030 Sustainable Development Goal Target 6.6 and Aichi Biodiversity Target 5. Our analysis indicated that the 1971 aim of the Ramsar Convention to stem the degradation of wetlands has not yet been achieved.
de Lauren O’Brien, Heather M. McGinness
In Wetlands Ecology and Management, 27(5-6) (December, 2019), 725-742
En ligne : link.springer.com[...]
Colonial-nesting waterbirds such as ibis and spoonbills (Threskiornithidae) can account for a significant proportion of energy flow through wetlands, particularly during large breeding events. However when food availability is reduced, chicks may starve and adults may abandon nests. If the energy required to rear chicks could be calculated, data quantifying prey energy value and availability could be used to develop landscape scale management targets to ensure that food requirements are met to support chicks until they attain independence, thereby maximising recruitment. We calculated ibis and spoonbill chick biometrics and energy requirements through (a) an international literature review, extracting and synthesising the best available growth and energy data; (b) new measurements of ibis and spoonbill chick biometrics for selected species; and (c) analysis of the resulting databases to construct growth curves and predict energy requirements for selected species. Here we present the first models of Royal Spoonbill growth and of Royal Spoonbill and Australian White Ibis chick energy requirements. The total energy estimated to raise a single Royal Spoonbill chick from hatching to independence was 71,290 kJ and for an Australian White Ibis chick was 67,160 kJ. Using prey energy values from the literature, extrapolations indicate that for either species, a nesting event of 1000 nests producing three chicks per nest would require an estimated ten tonnes of freshwater crayfish (Cherax destructor) or eight tonnes of invasive juvenile carp (Cyprinus carpio) to support chicks from hatching to independence. Effective water and wetland management is critical to optimise both energy availability in foraging sites and breeding success.
Gli uccelli del Parco Regionale della Maremma e aree limitrofe (Grosseto, Toscana, Italia)
de Pietro Giovacchini
In Rivista Italiana di Ornitologia, 89(1) (December, 2019), 7-99
En ligne : sisn.pagepress.org[...]
Il Parco Regionale della Maremma è una area protetta di 8902 ha nel settore costiero centrale della provincia di Grosseto, Toscana meridionale. Gli habitat che rappresentano l’area protetta possono essere così brevemente descritti: foce del fiume Ombrone e zone umide della Palude della Trappola; Monti dell’Uccellina (cima più elevata: Poggio Lecci, 417 m s.l.m.); un ampio comprensorio interno e pianeggiante dove coesistono attività zootecniche e coltivazioni agricole. Lo sviluppo costiero raggiunge i 25 km circa. Sono presenti 6 Siti della Rete Natura 2000 classificati come ZSC − Zona Speciale di Conservazione − secondo la Direttiva “Habitat” 92/43/ CE e/o come ZPS − Zona di Protezione Speciale − secondo la Direttiva “Uccelli” 2009/147/CE. La maggior parte dell’area presenta una scarsa rete viaria e limitati insediamenti umani con copertura boschiva in larga parte dovuta a formazioni vegetali sclerofilliche mediterranee. In questo lavoro viene presentato un elenco commentato degli uccelli noti per l’area protetta a partire dalla sua istituzione avvenuta il 05/06/1975 sino al 31/12/2018. In totale, le specie di Uccelli rilevate sono 295 (62,1% delle specie della Toscana ed il 52,5% delle specie note in Italia), mentre le specie nidificanti certe o probabili in tempi recenti (2008-2018) sono 84. Le specie di interesse comunitario presenti nell’Allegato I della Direttiva “Uccelli” 2009/147/CE sono 88, mentre quelle classificate come SPEC 1-3 “Species of European Conservation Concern” sono 33. L’area, con le zone umide “Bocca d’Ombrone” e “La Trappola” comprese nella Macrozona “Maremma Grossetana”, ricade all’interno della qualifica di sito di importanza internazionale per lo svernamento di Anser anser e Mareca penelope; inoltre è sito di importanza nazionale per Mareca strepera, Anas crecca, Anas acuta, Spatula clypeata, Ardea alba, Platalea leucorodia, Phoenicopterus roseus, Recurvirostra avosetta, Pluvialis apricaria, Calidris alpina, Vanellus vanellus, Gallinago gallinago, Numenius arquata, Tringa erythropus e Tringa totanus. L’area protetta è di importanza per specie nidificanti in Direttiva 2009/147/CE legate agli specchi lacustri costieri e agli spazi marini, ad incolti, pascoli, così come a zone con vegetazione arborea e arbustiva sparsa su affioramenti rocciosi, margini di boschi, ambienti parzialmente allagati ed ai litorali sabbiosi, quali ad esempio, con dati minimi, Pandion haliaetus (1 coppia), Burhinus oedicnemus (7-8 coppie), Charadrius alexandrinus (1 coppia), Caprimulgus europaeus (25 coppie), Coracias garrulus (13-15 coppie), Lanius collurio (1-5 coppie), Lullula arborea (10 coppie) e Anthus campestris (6-7 coppie). Dal 2015 si segnala il consolidamento della nidificazione di Ardea cinerea, rilevandone per la prima volta la riproduzione come garzaia.
de Gaëtan Lefebvre, Lauren Redmond, Christophe Germain, Elisa Palazzi, Silvia Terzago, Loic Willm, Brigitte Poulin
In Science of The Total Environment, 692 (November, 2019), 546-555
En ligne : www.sciencedirect.com[...]
Wetlands have been declining worldwide over the last century with climate change becoming an additional pressure, especially in regions already characterized by water deficit. This paper investigates how climate change will affect the values and functions of Mediterranean seasonally-flooded wetlands with emergent vegetation. We simulated the future evolution of water balance, wetland condition and water volumes necessary to maintain these ecosystems at mid- and late- 21st century, in 229 localities around the Mediterranean basin. We considered future projections of the relevant climatic variables under two Representative Concentration Pathway scenarios assuming a stabilization (RCP4.5) or increase (RCP 8.5) of greenhouse gases emissions. We found similar increases of water deficits at most localities around 2050 under both RCP scenarios. By 2100, however, water deficits under RCP 8.5 are expected to be more severe and will impact all localities. Simulations performed under current conditions show that 97% of localities could have wetland habitats in good state. By 2050, however, this proportion would decrease to 81% and 68% under the RCP 4.5 and RCP 8.5 scenarios, respectively, decreasing further to 52% and 27% by 2100. Our results suggest that wetlands can persist with up to a 400 mm decrease in annual precipitation. Such resilience to climate change is attributed to the semi-permanent character of wetlands (lower evaporation on dry ground) and their capacity to act as reservoir (higher precipitation expected in some countries during winter). Countries at highest risk of wetland degradation and loss are Algeria, Morocco, Portugal and Spain. Degradation of wetlands with emergent vegetation will negatively affect their biodiversity and the services they provide by eliminating animal refuges and primary resources for industry and tourism. A sound strategy to preserve these wetlands would consist of proactive management to reduce non-climate.
stressors. / Grâce à un partenariat avec l’institut des Sciences Atmosphériques et du Climat du Conseil National de la Recherche à Turin dans le cadre du projet H2020 Ecopotential, les projections météo pour les période 2050 et 2100 ont été estimées pour 229 localités autour de la Méditerranée et intégrées à mar-o-sel.net selon deux scénarios, l’un prévoyant une stabilisation des émissions de gaz à effet de serre (RCP4.5) et l’autre la poursuite de leur croissance actuelle (RCP8.5).
Des simulations ont permis de paramétrer des zones humides virtuelles pour chaque localité selon les conditions climatiques actuelles, puis en fonction des conditions climatiques de 2050 et 2100 selon les deux scénarios. Des valeurs seuils en termes de durée d’inondation et de sécheresse nécessaire au bon état des zones humides ont été définies pour que l’impact des changements climatiques puisse être visualiser en termes de dégradation ou transition d’écosystèmes.
Malgré un déficit hydrique accru sur l’ensemble de la Méditerranée en 2100 (de -239 mm ou -472 mm en moyenne selon les scénarios), certaines ZH pourront se maintenir en bon état grâce à leur caractère semi-permanent (évaporation moindre lorsque le sol est sec) et leur capacité de réservoir (précipitations accrues en hiver dans certains pays). Néanmoins, c’est seulement 68% (2050) et 27% (2100) des zones humides qui se maintiendront en bon état si les émissions de gaz à effet de serre poursuivent leur croissance actuelle. Le volume annuel moyen d’eau nécessaire pour préserver la biodiversité et les services rendus par ces écosystèmes variera d’un million (sites légèrement dégradés) à plus de 3,5 millions (sites en voie d’assèchement permanent) de litres d’eau par année et hectare. Les pays les plus à risque quant à la dégradation ou perte de zones humides sont l’Algérie, le Maroc, le Portugal et l’Espagne.
Estimating biodiversity changes in the Camargue wetlands: An expert knowledge approach
de Sara Fraixedas, Thomas Galewski, Sofia Ribeiro-Lopes, Jonathan Loh, Jacques Blondel, Hugo Fontes, Patrick Grillas, Philippe Lambret, Delphine Nicolas, Anthony Olivier, et al.
In PLOS ONE, 14(10) (24 oct. 2019), e0224235
En ligne : journals.plos.org[...]
Mediterranean wetlands are critical strongholds for biodiversity and the provision of ecosystem functions and services; yet, they are being severely degraded by a number of socio-economic drivers and pressures, including climate change. Moreover, we still lack comprehensive understanding of the extent to which biodiversity loss in Mediterranean wetlands will accelerate change in ecosystem processes. Here, we evaluate how changes in biodiversity can alter the ecosystem of the Camargue (southern France). We collected data on species presence/absence, trends and abundance over a 40-year period by combining observations from the scholarly literature with insights derived from expert knowledge. In total, we gathered more than 1500 estimates of presence/absence, over 1400 estimates of species abundance, and about 1400 estimates of species trends for eight taxonomic groups, i.e. amphibians, reptiles, breeding birds, fish, mammals, dragonflies (odonates), orthopterans and vascular plants. Furthermore, we used information on recently arrived species and invasive species to identify compositional changes across multiple taxa. Complementing targeted literature searches with expert knowledge allowed filling important gaps regarding the status and trends of biodiversity in the Camargue. Species trend data revealed sharp population declines in amphibians, odonates and orthopterans, while birds and plants experienced an average increase in abundance between the 1970s and the 2010s. The general increasing trends of novel and invasive species is suggested as an explanation for the changing abundance of birds and plants. While the observed declines in certain taxa reflect the relative failure of the protection measures established in the Camargue, the increasing exposure to novel and invasive species reveal major changes in the community structure of the different taxonomic groups. This study is the first attempt to assess changes in biodiversity in the Camargue using an expert knowledge approach, and can help manage the uncertainties and complexities associated with rapid social-ecological change in other Mediterranean wetlands.Bird ecological status of two internationally important wetlands ‘Ramsar sites and IBA’ in Algeria
de Adel Bezzalla, Moussa Houhamdi, Haroun Chenchouni
In Estuarine, Coastal and Shelf Science, 227 (October, 2019), 106308
En ligne : www.sciencedirect.com[...]
This study characterized the ecological status of birds at two Ramsar sites in northeastern Algeria, Chott Tinsilt (TNS) and Sebkhet Ezzemoul (EZZ). During the period 2015–2017, bird counting revealed that bird community was composed of 29 species and 11 families at TNS and 23 species and 10 families at EZZ. Bird species encountered across different habitats were classified into three ecological groups (waterbirds, open habitat birds and mountain birds). Besides, four ecological statuses (phenological status, faunal types, trophic status, and protection categories) were assigned to each species. Birds of both study wetlands have a biogeographical affinity with the faunal type ‘Palearctic’ (24.1% of species at TNS and 17.4% at EZZ). The Multiple factor analysis of ecological statuses crisscrossed with bird groups indicated that waterbirds are distinguished from other ecological groups because they are predominantly migrants (69.0% of species at TNS and 69.6% at EZZ) that use these two wetlands as wintering ground and migratory staging. Waterbirds included mostly invertebrate feeders, polyphagouss and piscivorous species. Mountain birds were distinguished as unique group because of species trophic status (especially carnivores and scavengers), their phenology (summer migrant breeders), and the abundance of certain protection categories. Open habitats birds were clustered as a separate because of the biogeographic faunal types. Our findings emphasized the importance of using ecological attributes of bird species in a multiple factor analysis to highlight information on the true status of birdlife. This survey characterized the diversity and ecological characteristics of birds of two Ramsar sites, which represent a true natural heritage of proven ecological and socio-economic importance at regional and national scales.
de Georgios A. Kordelas, Ioannis Manakos, Gaëtan Lefebvre, Brigitte Poulin
In Remote Sensing, 11(19) (Septembre, 2019), 2251
En ligne : www.mdpi.com[...]
Flooding periodicity is crucial for biomass production and ecosystem functions in wetland areas. Local monitoring networks may be enriched by spaceborne derived products with a temporal resolution of a few days. Unsupervised computer vision techniques are preferred, since human interference and the use of training data may be kept to a minimum. Recently, a novel automatic local thresholding unsupervised methodology for separating inundated areas from non-inundated ones led to successful results for the Doñana Biosphere Reserve. This study examines the applicability of this approach to Camarque Biosphere Reserve, and proposes alternatives to the original approach to enhance accuracy and applicability for both Camargue and Doñana wetlands in a scientific quest for methods that may serve accurately biomes at both protected areas. In particular, it examines alternative inputs for automatically estimating thresholds while applying various algorithms for estimating the splitting thresholds. Reference maps for Camargue are provided by local authorities, and generated using Sentinel-2 Band 8A (NIR) and Band 12 (SWIR-2). The alternative approaches examined led to high inundation mapping accuracy. In particular, for the Camargue study area and 39 different dates, the alternative approach with the highest overall Kappa coefficient is 0.84, while, for the Doñana Biosphere Reserve and Doñana marshland (a subset of Doñana Reserve) and 7 different dates, is 0.85 and 0.94, respectively. Moreover, there are alternative approaches with high overall Kappa for all areas, i.e., at 0.79 for Camargue, over 0.91 for Doñana marshland, and over 0.82 for Doñana Reserve. Additionally, this study identifies the alternative approaches that perform better when the study area is extensively covered by temporary flooded and emergent vegetation areas (i.e., Camargue Reserve and Doñana marshland) or when it contains a large percentage of dry areas (i.e., Doñana Reserve). The development of credible automatic thresholding techniques that can be applied to different wetlands could lead to a higher degree of automation for map production, while enhancing service utilization by non-trained personnel.Introducing WIW for Detecting the Presence of Water in Wetlands with Landsat and Sentinel Satellites
de Gaëtan Lefebvre, Aurélie Davranche, Loic Willm, Julie Campagna, Lauren Redmond, Clément Merle, Anis Guelmami, Brigitte Poulin
In Remote Sensing, 11(19) (Septembre, 2019), 18
En ligne : www.mdpi.com[...]
Many wetlands are characterized by a vegetation cover of variable height and density over time. Tracking spatio-temporal changes in inundation patterns of these wetlands remains a challenge for remote sensing. Water In Wetlands (WIW) was predicted using a dichotomous partitioning of reflectance values encoded based on ground-truth (n = 4038) and optical-space derived (n = 7016) data covering all land cover types (n = 17) found in the Rhône delta, southern France. The models were developed with spectral data from Sentinel 2, Landsat 7, and Landsat 8 sensors, hence providing a monitoring tool that covers a 35-year period (same sensor for Landsat 5 and 7). A single model combining the near infrared (NIR ≤ 0.1558 to 0.1804, depending on sensors) and short-wave infrared (SWIR2 ≤ 0.0871 to 0.1131) wavelengths was identified by three independent analyses, each one using a different satellite. Overall accuracy of water maps ranged from 89% to 94% for the training samples and from 90% to 94% for the validation samples, encompassing standard water indices that systematically underestimate flooding duration under vegetation cover. Sentinel 2 provided the highest performance with a kappa coefficient of 0.82 for both samples. Such tool will be most useful for monitoring the water dynamics of seasonal wetlands, which are particularly sensitive to climate change while providing multiple services to humankind. Considering the high temporal resolution of Sentinel 2 (every 5 days), cumulative water maps built with the WIW logical rule could further be used for mapping a wide range of wetlands which are either periodically or permanently flooded.Mexico, une ville sur une zone humide
de Luis Zambrano, Jocelyn Champagnon
In Zones Humides Infos, 97-98 (Eté 2019), 7L’état des zones humides dans le monde et en Méditerranée
de Christian Perennou, Laurent Chazee, Thomas Galewski, Ilse Geijzendorffer, Anis Guelmami
In Zones Humides Infos, 97-98 (Eté 2019), 20-21Le paysage, l’émotion et l’éducation de terrain, vecteurs de souvenir
de Laurent Chazee, Melanie Requier-Desjardins
In Zones Humides Infos, 97-98 (Eté 2019), 24-26Assessing risk of collapse of Lake Burullus Ramsar site in Egypt using IUCN Red List of Ecosystems
de Somaya Magdy M. Ghoraba, Marwa Waseem A. Halmy, Boshra B. Salem, Nadia Badr E. Badr
In Ecological Indicators, 104 (09/2019), 172-183
En ligne : linkinghub.elsevier.com[...]
The IUCN Red List of Ecosystems (RLE) assessment is a new powerful scheme that identifies ecosystems that are at risk of collapse due to global environmental changes, which can help any mitigation actions aimed at conserving and rescuing these natural ecosystems. The current study applied RLE assessment protocol on Lake Burullus ecosystem, a highly productive wetland ecosystem, Ramsar site and International Bird Area (IBA) of Egypt. A conceptual model of the key ecosystem processes for Burullus wetland was constructed. The application of RLE followed the standard protocol for the first four criteria; (A) declines in distribution, (B) restricted distribution, (C) degradation of the abiotic components, and (D) regarding the assessment of the disruption of biotic processes and interactions. However, data were insufficient for assessing Criterion (E) that entails conducting quantitative estimates of the risk of collapse. Multi-date satellite images were obtained and processed to estimate the changes in the spatial distribution under criteria (A) and (B) of the study area. For evaluating Criteria (C) and (D), long-term data were collected from literature and previous works to cover the time frame of the assessment as much as possible. The results from the RLE assessment revealed that the status of the ecosystem is Critically Endangered (CR), which was attributed to various types of threats that caused degradation of the natural quality and integrity of the ecosystem. Although the RLE assessment provides a coherent approach for identifying ecosystems vulnerable to human-induced changes; data insufficiency can be an impediment for the efficient application of the RLE assessment. Remotely-sensed data can help in derivation of suitable spectral indicators of the status of the ecosystems structure and functioning that might overcome some of the challenges of data adequacy and relevance to the RLE assessment especially for the understudied and data-deficient ecosystems.Climatic changes, hydrology and trophic status of Lake Oubeira (extreme northeast of Algeria)
de Yacine Messerer, Abdelhalek Retima, Aicha B. Amira, Abdellah B. Djebar
In AACL Bioflux, 12(4) (August, 2019), 1442-1457
En ligne : www.bioflux.com.ro[...]
The Oubeira is the largest freshwater lake situated in the extreme eastern north part of Algeria. It is more particularly regarded as an integral part of El-Kala National Park. It is located in one of the most watered regions of the country between 800 and 900 mm. In order to characterize it from the hydrological point of view, a follow-up and a bi-monthly analysis of the volume waters and various parameters such as temperature, pH, dissolved oxygen (DO) , ammonium (NH4), nitrates (NO3), nitrites (NO2), orthophosphate (PO4), dissolved organic nitrogen (DON), dissolved organic phosphate (DOP), suspended particulate matter (SPM), particulate organic carbon (POC) and chlorophyll a were carried out between March 2004 and April 2005. The temperature of the water is similar across the whole surface of the lake and varies between 8 and 22°C. The pH is slightly acid to slightly alkaline and ranges from 6.2 to 8.9. Dissolved oxygen contents are viable with a maximum of 8.98 mg L- 1 . The water volume of the lake ranges from 23 x 106 to 59.70 x 106 m3 from one season to another. There is some compensation between the values of dissolved nutrients and organic matter over the study period. The concentrations of dissolved nutrients ranged from 0 to 21.50 μmol L- 1 for ammonium (NH4), from 0.038 to 21.58 μmol L- 1 for nitrates (NO3), and from 0 to 0.38 μmol L- 1 for orthophosphates (PO4), and for dissolved organic nitrogen (DON) from 0.58 to 67.17 μmol L- 1 and also dissolved organic phosphorus (DOP) from 0 to 2.87 μmol L- 1 . The highest concentrations of the chlorophyll a are measured during the dry season and evolve from 7.58 to 394.52 mg m- 3 . We consider that our lake passes through two trophic states. A phase through which waters of the lake are mesotrophic when the rate of renewal of the waters is important from January to May. A second phase in which waters of the lake are hypereutrophic favored is in summer season extending from June to September. This leads to the reduction of lake waters to their lowest levels. Climate warming, rainfall patterns in the study area, and the extent of clogging of the lake outfall have a major impact on the evolution of the lake waters. These phenomena could plunge the lake into an era of strict endoreism that will swing its waters towards total destruction and will result in the filling of the basin of the lake.
Key Words: Oubeira Lake, dissolved nutrients, chlorophyll a, suspended solids, water flow.
de Adel Bezzalla, Moussa Houhamdi, Mohamed Cherif Maazi, Haroun Chenchouni
In Avian Biology Research, 12(3) (August, 2019), 77-95
En ligne : journals.sagepub.com[...]
Several North African wetlands are classified as wetlands of international importance (Ramsar sites and Important Bird Area) because thousands of Shelducks (Tadorna tadorna) winter in these habitats. However, Shelduck’s patterns of habitat use in these protected wetlands during the wintering season are still hindered by lack of information in arid and semi-arid regions regarding population dynamics and the effects of climate variables. This ornithological survey aims to study population dynamics and temporal patterns of diurnal activities of the Shelduck at two Ramsar and Important Bird Area sites (Chott Tinsilt and Sebkhet Ezzemoul) with respect to the effect of climatic parameters of the habitat in order to deepen our understanding of wintering strategies and habitat use. Populations were weekly censused from 06:00 to 19:00 during the entire wintering season (September 2015–May 2016). Diurnal behavioural activities were monitored at the same rate, and then the variation of time budget was tested using generalized linear model to determine the effects of climate variables and conspecific density dependence. The Shelduck was observed at both sites from the end of November and remained there until the total desiccation of both lakes in early May. Trends of Shelduck’s population dynamics differed between the two sites. Generalized linear models revealed the significant effects of temperature, wind speed and number of snowy days on population dynamics. Feeding was the main diurnal activity of the Shelduck at both sites with 80.2% of time budget at Chott Tinsilt (mainly feeding at lake shores) and 82% at Sebkhet Ezzemoul (mainly feeding in water). The generalized linear models showed that the variation of time budget allocated to different diurnal activities was not density-dependent, but rather it was negatively affected by the increase of air temperature. Significant effects of the interaction between population size and some climatic variables were found and discussed. During the whole wintering season, Chott Tinsilt and Sebkhet Ezzemoul play an important ecological role since they offer a wideranging diurnal forging habitat and a shelter for thousands of this waterfowl.The Role of Wetlands for Climate Change Mitigation and Biodiversity Conservation
de T. T. Dinsa, D. O. Gemeda
In Journal of Applied Sciences and Environmental Management, 23(7) (July, 2019), 1297-1300-1300
En ligne : www.ajol.info[...]
Wetland is crucial in supporting biodiversity conservation and climate change regulation. A wetland ecosystem has been influenced by anthropogenic driven climate change. The main objective of this paper is to analyze the role of wetlands for climate change mitigation and biodiversity conservation through literature review. Wetland is vulnerable to climate change through alterations of hydrological regimes that lead to changes in quantity and quality of water. Climate change is undoubtedly the most pervasive, complex and challenging of the global environmental issues facing contemporary society and it affects all aspects of development. Wetlands play a key role in hydrological and biogeochemical cycles, and provide a wide range of ecosystem goods and services to humankind. In spite of these facts, wetlands are considered as wastelands in the past, which contributes for deterioration of wetlands in several places. Thus, strong environmental policy is required for the conservation of wetland ecosystem.The avifauna of the Zigoneni dam basin (Argeş county, Romania), observed in 2013
de Adrian Mestecăneanu
In Travaux du Muséum d’Histoire Naturelle "Grigore Antipa", 62(1) (July, 2019), 99-124
En ligne : travaux.pensoft.net[...]
Some aspects regarding the breeding of the birds from Zigoneni Basin that belongs to the protected area ROSPA0062 the Dam Basins of the Argeş River are presented in this paper. 37 species were observed here, between May and July 2013, through the point counts method, within a radius of 100 m. On one side Acrocephalus palustris , A. scirpaceus, A. arundinaceus, Alcedo atthis, Fulica atra, Oriolus oriolus and Parus major were the most frequent species and on the other side A. palustris and Fulica atra were the most abundant. At the level of the habitat mosaic of the water shore, A. palustris (0.88 p./ha), A. scirpaceus and F. atra (each with 0.32 p./ha) and A. schoenobaenus, A. arundinaceus, Phylloscopus collybita and Pica pica (each with 0.24 p./ha) had the highest estimated densities. Additionally, 14 species dependent on wetlands were observed through the itinerary method. Other considerations about the ecological indices and the efficiency of the methods were also made.
de Nigel G. Taylor, Patrick Grillas, M.S. Fennessy, E. Goodyer, L.L.B. Graham, E. Karofeld, R.A. Lindsay, D.A. Locky, N. Ockendon, A. Rial, et al.
In Mires and Peat, 24 (June, 2019), 1-21
En ligne : www.repository.cam.ac.uk[...]
Peatlands are valuable but threatened ecosystems. Intervention to tackle direct threats is often necessary, but should be informed by scientific evidence to ensure it is effective and efficient. Here we discuss a recent synthesis of evidence for the effects of interventions to conserve peatland vegetation - a fundamental component of healthy, functioning peatland ecosystems. The synthesis is unique in its broad scope (global evidence for a comprehensive list of 125 interventions) and practitioner-focused outputs (short narrative summaries in plain English, integrated into a searchable online database). Systematic literature searches, supplemented by recommendations from an international advisory board, identified 162 publications containing 296 distinct tests of 66 of the interventions. Most of the articles studied open bogs or fens in Europe or North America. Only 36 interventions were supported by sufficient evidence to assess their overall effectiveness. Most of these interventions (85 %) had positive effects, overall, on peatland vegetation although this figure is likely to have been inflated by publication bias. We discuss how to use the synthesis, critically, to inform conservation decisions. Reflecting on the content of the synthesis we make suggestions for the future of peatland conservation, from monitoring over appropriate timeframes to routinely publishing results to build up the evidence base.Emerging threats and persistent conservation challenges for freshwater biodiversity
de Andrea J. Reid, Andrew K. Carlson, Irena F. Creed, Erika J. Eliason, Peter A. Gell, Pieter T. J. Johnson, Karen A. Kidd, Tyson J. MacCormack, Julian D. Olden, Steve J. Ormerod, et al.
In Biological Reviews, 94(3) (June, 2019), 849-873
En ligne : onlinelibrary.wiley.com[...]
In the 12 years since Dudgeon et al. (2006) reviewed major pressures on freshwater ecosystems, the biodiversity crisis in the world’s lakes, reservoirs, rivers, streams and wetlands has deepened. While lakes, reservoirs and rivers cover only 2.3% of the Earth’s surface, these ecosystems host at least 9.5% of the Earth’s described animal species. Furthermore, using the World Wide Fund for Nature’s Living Planet Index, freshwater population declines (83% between 1970 and 2014) continue to outpace contemporaneous declines in marine or terrestrial systems. The Anthropocene has brought multiple new and varied threats that disproportionately impact freshwater systems. We document 12 emerging threats to freshwater biodiversity that are either entirely new since 2006 or have since intensified: (i) changing climates; (ii) e-commerce and invasions; (iii) infectious diseases; (iv) harmful algal blooms; (v) expanding hydropower; (vi) emerging contaminants; (vii) engineered nanomaterials; (viii) microplastic pollution; (ix) light and noise; (x) freshwater salinisation; (xi) declining calcium; and (xii) cumulative stressors. Effects are evidenced for amphibians, fishes, invertebrates, microbes, plants, turtles and waterbirds, with potential for ecosystem-level changes through bottom-up and top-down processes. In our highly uncertain future, the net effects of these threats raise serious concerns for freshwater ecosystems. However, we also highlight opportunities for conservation gains as a result of novel management tools (e.g. environmental flows, environmental DNA) and specific conservation-oriented actions (e.g. dam removal, habitat protection policies, managed relocation of species) that have been met with varying levels of success. Moving forward, we advocate hybrid approaches that manage fresh waters as crucial ecosystems for human life support as well as essential hotspots of biodiversity and ecological function. Efforts to reverse global trends in freshwater degradation now depend on bridging an immense gap between the aspirations of conservation biologists and the accelerating rate of species endangerment.
de Sarah E. Darrah, Yara Shennan-Farpon, Jonathan Loh, Nick C. Davidson, C. Max Finlayson, Royal C. Gardner, Matt J. Walpole
In Ecological Indicators, 99 (Avril, 2019), 294-298
En ligne : linkinghub.elsevier.com[...]
Indicators of status and trends in wetland extent are essential for monitoring progress towards the environmental targets set by the Convention on Biological Diversity (CBD), the United Nations Sustainable Development Goals (SDGs) and the Ramsar Convention on Wetlands. Here, we test the value of the Wetland Extent Trends (WET) index as an updatable indicator of trends in wetland area and its application to global and regional scale assessments and national reporting. We expand the indicator to include a regional trend for Latin America and the Caribbean and a global human-made WET index. Based on a sample of over 2000 wetland records, natural wetland extent declined on average by 35% globally, at an increasing rate from 1970 to 2015. Human-made wetlands, however, increased by 233% from 1970 to 2014. The continuing decline in natural wetland extent suggests that global targets will not be achieved without significant further efforts.Worth of wetlands: revised global monetary values of coastal and inland wetland ecosystem services
de N. C. Davidson, A. A. van Dam, C. M. Finlayson, R. J. McInnes
In Marine and Freshwater Research, 10.1071/MF18391 (March, 2019)
En ligne : www.publish.csiro.au[...]
In this study, we have re-estimated the 2011 global monetary values of natural wetland ecosystem services using new information on the areas of different coastal and inland wetland classes, and included estimates for forested wetlands. The 2011 global monetary value of natural wetland ecosystem services is now estimated at Int$47.4 trillion per year, 43.5% of the value of all natural biomes. Despite forming only ~15% of global natural wetland area, coastal wetlands are estimated to deliver 43.1% (Int$20.4 trillion per year) of the total global ecosystem services monetary value of all natural wetland classes. There is a need to further refine these value estimates by factoring in other determinants of wetland ecosystem service monetary value, by disaggregating unit monetary values to each wetland class and by updating unit monetary values with more recent sources, especially for ecosystem services with no, or few, value estimates.A meta-decision-analysis approach to structure operational and legitimate environmental policies
de Mourad Choulak, Damien Marage, Manon Gisbert, Melanie Paris, Yves Meinard
In Science of The Total Environment, 655 (March, 2019), 384-394
Environmental policies are implemented in complex socio-economic settings, where numerous stakeholders hold different and potentially conflicting values. In addition to being scientifically well-founded, the experts' recommendations on which these policies are based therefore also need to be operational and legitimate. Multi-criteria decision-analysis (MCDA) is often used to solve management problems, but studies in the literature rarely place importance on the way stakeholders perceive researchers' interventions (which implies a lack of legitimacy), and most managers lack the skills to reproduce routinely the operations involved (which implies a lack of operationality). We use MCDA methodology in a different approach: "meta-decision-analysis" (Meta-DA). As researchers, instead of striving to identify the best way for us to solve managers' problems, we identify the actors (the decision-aid providers, DAPs) who are best placed to help managers, and we provide DAPs with the necessary tools. Implementing this approach involves three tasks: T1-identifying a legitimate DAP who will provide decision-aid to managers in routine policy implementations; T2-identifying, among the decisions involved in solving managers' problems, those for which managers and the stakeholders concerned consider that some actors have particular legitimacy; T3-designing tools that are compatible with both the DAP's skills and legitimacy constraints. We applied this approach, structured around T1-3, to wetland prioritization in a French administrative region (Bourgogne-Franche-Comte). This application illustrates the feasibility and usefulness of our approach. Our approach entails recommendations for various kinds of actors involved in environmental policies: For researchers, it provides a research agenda to develop new applications of MCDA. For managers and potential DAPs, it suggests that, for some of the problems they face collectively, they should seek the help of researchers to implement a Meta-DA approach. For policy-makers, it suggests that, by encouraging Meta-DA, for example through dedicated funding schemes, they could improve the effectiveness of environmental policies. (C) 2018 Elsevier B.V. All rights reserved.
de Adel Bezzalla, Moussa Houhamdi, Mohamed Cherif Maazi, Haroun Chenchouni
In Avian Biology Research, 10.1177/1758155919835122 (2019), 1 –19
En ligne : journals.sagepub.com[...]
Several North African wetlands are classified as wetlands of international importance (Ramsar sites and Important Bird Area) because thousands of Shelducks (Tadorna tadorna) winter in these habitats. However, Shelduck’s patterns of habitat use in these protected wetlands during the wintering season are still hindered by lack of information in arid and semi-arid regions regarding population dynamics and the effects of climate variables. This ornithological survey aims to study population dynamics and temporal patterns of diurnal activities of the Shelduck at two Ramsar and Important Bird Area sites (Chott Tinsilt and Sebkhet Ezzemoul) with respect to the effect of climatic parameters of the habitat in order to deepen our understanding of wintering strategies and habitat use. Populations were weekly censused from 06:00 to 19:00 during the entire wintering season (September 2015–May 2016). Diurnal behavioural activities were monitored at the same rate, and then the variation of time budget was tested using generalized linear model to determine the effects of climate variables and population size dependency. The Shelduck was observed at both sites from the end of November and remained there until the total desiccation of both lakes in early May. Trends of Shelduck’s population dynamics differed between the two sites. Generalized linear models revealed the significant effects of temperature, wind speed and number of snowy days on population dynamics. Feeding was the main diurnal activity of the Shelduck at both sites with 80.2% of time budget at Chott Tinsilt (mainly feeding at lake shores) and 82% at Sebkhet Ezzemoul (mainly feeding in water). The generalized linear models showed that the variation of time budget allocated to different diurnal activities was not population dependent, but rather it was negatively affected by the increase of air temperature. Significant effects of the interaction between population size and some climatic variables were found and discussed. During the whole wintering season, Chott Tinsilt and Sebkhet Ezzemoul play an important ecological role since they offer a wide-ranging diurnal forging habitat and a shelter for thousands of this waterfowl.
de Shelby Servais, John S. Kominoski, Sean P. Charles, Evelyn E. Gaiser, Viviana Mazzei, Tiffany G. Troxler, Benjamin J. Wilson
In Geoderma, 337 (03/2019), 1291-1300
En ligne : linkinghub.elsevier.com[...]
Wetlands can store significant amounts of carbon (C), but climate and land-use change increasingly threaten wetland C storage potential. Carbon stored in soils of freshwater coastal wetlands is vulnerable to rapid saltwater intrusion associated with sea-level rise and reduced freshwater flows. In the Florida Everglades, unprecedented saltwater intrusion is simultaneously exposing wetlands soils to elevated salinity and phosphorus (P), in areas where C-rich peat soils are collapsing. To determine how elevated salinity and P interact to influence microbial contributions to C loss, we continuously added P (~0.5 mg P d−1) and salinity (~6.9 g salt d−1) to freshwater Cladium jamaicense (sawgrass) peat monoliths for two years. We measured changes in porewater chemistry, microbial extracellular enzyme activities, respiration rates, microbial biomass, root litter breakdown rates (k), and soil elemental composition after short (57 d), intermediate- (392 d), and long-term (741 d) exposure. After 741 days, both β-1,4-glucosidase activity (P 0.05) with added salinity and was unaffected by added P. Soil respiration rates decreased after 372 d exposure to salinity (P = 0.05) and did not change with P exposure. Root litter k increased by 1.5× with added P and was unaffected by salinity exposure (P > 0.01). Soil %C decreased by approximately 1.3× after 741 days of salinity exposure compared to freshwater controls (PThe politics of interbasin transfers: Socio-environmental impacts and actor strategies in Tunisia
de Wafa Ben Fraj, Mohamed Elloumi, Francois Molle
In Natural Resources Forum, 0(10.1111/1477-8947.12165) (February, 2019)
En ligne : onlinelibrary.wiley.com[...]
Mediterranean wetlands are of key interest in the preservation of biodiversity. However, their ecological water requirement is in constant competition with human uses, particularly in a context of aridity and climate change. This paper examines the case of the Ichkeul Lake-Lagoon system located in the north of Tunisia in a river basin that is heavily contributing to the water supply of southern regions through water transfers. It maps out the various actors involved, their stakes, discourses and strategies, and explains the current degradation of the Ichkeul system by unpacking the decision-making power of these actors. It confirms that marginal social groups, ecosystems and next generations are the main parties affected by current water allocation patterns.A More Effective Ramsar Convention for the Conservation of Mediterranean Wetlands
de Ilse R. Geijzendorffer, Coralie Beltrame, Laurent Chazee, Elie Gaget, Thomas Galewski, Anis Guelmami, Christian Perennou, Nadège Popoff, Carlos A. Guerra, Roxanne Leberger, et al.
In Frontiers in Ecology and Evolution, 7 (February, 2019)
En ligne : www.frontiersin.org[...]
The Ramsar Convention is the multilateral agreement aimed at protecting wetlands globally. Wetlands are particularly recognized for their role in the Mediterranean biodiversity hotspot by providing key habitats for endemic and migratory species, directly contributing benefits to the lives of people and being an integral part of their culture. In response to this importance, the Mediterranean Wetlands Observatory publishes Mediterranean Wetland Outlooks on the state and trends of Mediterranean wetlands; the first edition in 2012 (MWO1) and the second edition in 2018 (MWO2). In this paper, we used the results of the two Mediterranean Wetland Outlooks to highlight ways to increase the impact of the Ramsar Convention by identifying the spatial dimensions of detected biodiversity trends as well as the societal developments and estimated impacts of global change and protection status.Effect of restoration on saltmarsh carbon accumulation in Eastern England
de Burden A., Garbutt A., Evans C. D.
In Biology Letters, 15(1) (January, 2019), 20180773
En ligne : royalsocietypublishing.org[...]
Wetland soils are globally important carbon stores, and natural wetlands provide a sink for atmospheric carbon dioxide (CO2) through ongoing carbon accumulation. Recognition of coastal wetlands as a significant contributor to carbon storage (blue carbon) has generated interest into the climate change mitigation benefits of restoring or recreating saltmarsh habitat. However, the length of time a re-created marsh will take to become functionally equivalent to a natural (reference) system, or indeed, whether reference conditions are attainable, is largely unknown. Here, we describe a combined field chronosequence and modelling study of saltmarsh carbon accumulation and provide empirically based predictions of changes in the carbon sequestration rate over time following saltmarsh restoration. Carbon accumulation was initially rapid (average 1.04 t C ha−1 yr−1 during the first 20 years), slowing to a steady rate of around 0.65 t C ha−1 yr−1 thereafter. The resulting increase in C stock gave an estimated total C accumulation of 74 t C ha−1 in the century following restoration. This is approximately the same as our observations of natural marsh C content (69 t C ha−1), suggesting that it takes approximately 100 years for restored saltmarsh to obtain the same carbon stock as natural sites.
de Feirouz Touhami, Hocein Bazaïri, Bouabid Badaoui, Ali MORABBI, Abdelaziz Benhoussa
In Cahiers de biologie marine, 60 (2019), 41-50
En ligne : application.sb-roscoff.fr[...]
Merja Zerga is the most important wetland for wintering shorebirds in Morocco. To understand the role of intertidal habitats as feeding areas, a study that aims to analyse the composition, structure and spatial organization of macrobenthic fauna in the main habitats frequented by shorebirds has been conducted. From the analysis of 570 samples distributed over 19 stations, 46 species of benthic macrofauna, dominated by Molluscs and Polychaetes, were identified. Densities ranged from 305 to 25 663 individuals.m-2, with an average of 5 764 ind.m-2, and biomasses ranged from 3.92 to 52.65 g.m-2, with an average of 20.07 g.m-2. Four benthic assemblages were identified, distributed along a downstreamupstream gradient. Hydrological and sedimentary parameters, as well as the presence or absence of seagrass beds, were the main factors that structure the distribution and the functioning of benthic assemblages. Distribution maps of benthic assemblages, representing the main prey for shorebirds, are essential tools for managers to identify areas with high conservation issues for aquatic birds. / Structure et organisation spatiale de la faune macrobenthique des habitats intertidaux fréquentés par les oiseaux limicoles hivernants dans le lagon de Merja Zerga (Site Ramsar marocain). Merja Zerga constitue la zone humide la plus importante pour l'hivernage des limicoles au Maroc. Pour mieux comprendre le rôle que jouent les habitats intertidaux de ce site pour l'alimentation de ces oiseaux durant l'hiver, une étude visant à analyser la structure et l'organisation spatiale de la faune macrobenthique dans les principaux habitats fréquentés par les limicoles a été réalisée. L'analyse de 570 échantillons repartis sur 19 stations a permis d'identifier 46 espèces macrozoobenthiques, dominées par les Mollusques et les Polychètes. Les densités observées variaient entre 305 et 25 663 individus.m-2 (moyenne de 5 764 ind.m-2) et les biomasses, entre 3,92 et 52,65 g.m-2 (moyenne de 20,07 g.m-2). Quatre assemblages benthiques ont été identifiés, se répartissant selon un gradient aval-amont. Les paramètres hydrologiques et sédimentaires, ainsi que la présence ou l'absence d'herbiers de phanérogames, sont les principaux facteurs régissant la structure de ces communautés. Les cartes de répartition des assemblages benthiques des zones d'alimentation des limicoles, constituent des outils incontournables permettant aux gestionnaires d'identifier les zones à forts enjeux de conservation de l'avifaune aquatique.
de Siham El Malki, Latifa Joulami, Mouna El Mdari, Rhimou El Hamoumi
In Wader Study, 125(2) (October, 2018), 107 – 114
En ligne : www.waderstudygroup.org[...]
Nest site selection and breeding biology of Kentish Plover Charadrius alexandrinus were studied in the Sidi Moussa saltpans, a part of the Moroccan Ramsar site ‘Sidi Moussa-Walidia’, in two habitat types (natural marshes and saltpans) during two breeding seasons (2011 and 2012). We followed 32 nests during the egg-laying period (late March to late June). Most nests (70%, n = 22) were located less than one meter from vegetation and the mean height of the vegetation around the nest was 19 ± 2 cm. Mean distance to the nearest water was around 2 m (212 ± 24 cm). The mean clutch size was 2.3 ± 0.1 eggs per nest. Mean egg volume was 8.18 ± 0.19 cm3. Nesting success was 38%. Human disturbance was the main cause (85%) of clutch failure. Mean clutch size and mean egg volume in Sidi Moussa were lower than those reported by other studies. However, with a hatch success similar or higher than those in several natural or man-made habitats, Sidi Moussa salt pans are an important nesting habitat for Kentish Plovers.Future response of global coastal wetlands to sea-level rise
de Mark Schuerch, Tom Spencer, Stijn Temmerman, Matthew L. Kirwan, Claudia Wolff, Daniel Lincke, Chris J. McOwen, Mark D. Pickering, Ruth Reef, Athanasios T. Vafeidis, et al.
In Nature, 561(7722) (September, 2018), 231-234
En ligne : www.nature.com[...]
The response of coastal wetlands to sea-level rise during the twenty-first century remains uncertain. Global-scale projections suggest that between 20 and 90 per cent (for low and high sea-level rise scenarios, respectively) of the present-day coastal wetland area will be lost, which will in turn result in the loss of biodiversity and highly valued ecosystem services1,2,3. These projections do not necessarily take into account all essential geomorphological4,5,6,7 and socio-economic system feedbacks8. Here we present an integrated global modelling approach that considers both the ability of coastal wetlands to build up vertically by sediment accretion, and the accommodation space, namely, the vertical and lateral space available for fine sediments to accumulate and be colonized by wetland vegetation. We use this approach to assess global-scale changes in coastal wetland area in response to global sea-level rise and anthropogenic coastal occupation during the twenty-first century. On the basis of our simulations, we find that, globally, rather than losses, wetland gains of up to 60 per cent of the current area are possible, if more than 37 per cent (our upper estimate for current accommodation space) of coastal wetlands have sufficient accommodation space, and sediment supply remains at present levels. In contrast to previous studies1,2,3, we project that until 2100, the loss of global coastal wetland area will range between 0 and 30 per cent, assuming no further accommodation space in addition to current levels. Our simulations suggest that the resilience of global wetlands is primarily driven by the availability of accommodation space, which is strongly influenced by the building of anthropogenic infrastructure in the coastal zone and such infrastructure is expected to change over the twenty-first century. Rather than being an inevitable consequence of global sea-level rise, our findings indicate that large-scale loss of coastal wetlands might be avoidable, if sufficient additional accommodation space can be created through careful nature-based adaptation solutions to coastal management.
de Brigitte Poulin, Gaëtan Lefebvre
In Insect Science, 25(4) (2018/08/01), 542-548
En ligne : onlinelibrary.wiley.com[...]
Bacillus thuringiensis var. israelensis (Bti) is the most commonly used larvicide to control mosquitoes worldwide. Considered as nontoxic to most organisms, Bti can nevertheless cause trophic perturbations to natural communities by reducing the abundance of Chironomidae, which are a key element of wetland food webs. Since August 2006, up to 8400 of the 33 000 ha of mosquito larval biotopes in the Camargue (Rhône delta, in southern France), are monitored by a public agency and Bti‐sprayed (aqueous solution of VectoBac 12AS at 2.5 L/ha) whenever mosquito larvae (Ochlerotatus caspius and Oc. detritus) appeared in water bodies. This resulted in 30–50 aerial treatments/year, in addition to ground spraying of unknown frequency. The sprayed habitats include Phragmites australis reedbeds, which support a specific avifauna of conservation concern. We compared the abundance of invertebrate prey available to passerine birds at treated and control sites relative to the predicted values based on hydrology over a 9‐year period. Food available to reed passerines was significantly reduced at treated areas, translating into a 34% decrease in breeding birds based on predictive modeling. The most affected arthropods were Diptera, Aranaea, Coleoptera, and Hymenoptera. No cumulative effects were observed over time, but the recovery of the invertebrate assemblage after the cessation of mosquito control was delayed due to Bti spore persistence and proliferation in the sediments. While hydrology remains a prime factor influencing primary and secondary productivity of the Camargue reed marshes, Bti spraying had significant negative effects on animal communities at several trophic levels.
The Second Warning to Humanity–Providing a Context for Wetland Management and Policy
de C. M. Finlayson, Gillian T. Davies, William R. Moomaw, G. L. Chmura, Susan M. Natali, J. E. Perry, N. Roulet, Ariana E. Sutton-Grier
In Wetlands, https://doi.org/10.1007/s13157-018-1064 (July 2018), 1–5
The Second Warning to Humanity provides a clarion call for wetland researchers and practitioners given the loss and degradation of wetlands, the declining availability of fresh water, and the likely consequences of climate change. A coordinated response and approach to policies has the potential to prevent further degradation and support resilient wetlands that can provide a range of ecosystem services, including buffering wetlands from climate impacts, and avoiding major climate amplification from temperature-induced release of additional carbon dioxide and methane while addressing the causes and consequences of global climate change. The Warning to Humanity also provides an opportunity for organisations such as the Society of Wetland Scientists to raise the profile of wetlands and to initiate a discussion on how to respond and change direction from the destructive development trajectory that led to wetland loss and degradation. It also provides a signal for a reappraisal of the effectiveness of the implementation of the Ramsar Convention on Wetlands as an international mechanism for ensuring the sustainability of wetlands. KW
Climate change Ramsar convention Wetlands Second warning to humanityRelationships of Native and Exotic Strains of Phragmites australis to Wetland Ecosystem Properties
de L. A. Volesky, S. Iqbal, J. J. Kelly, P. Geddes
In Wetlands, 38(3) (June, 2018), 577-589
Invasions by exotic plant species like Phragmites australis can affect wetlands and the services they provide, including denitrification. Native and exotic Phragmites strains were genetically verified in 2002 but few studies have compared their ecosystem effects. We compared relationships between native and exotic Phragmites and environmental attributes, soil nutrient concentrations, and abundance and activity of soil denitrifying bacteria. There were no significant differences for any measured variables between sites with exotic and native strains. However, there were significant positive correlations between native Phragmites stem density and soil nutrient concentrations and denitrification rates. Furthermore, denitrifying bacterial abundance was positively correlated with nitrate concentration and denitrification rates. Additionally, there were significant negative correlations between water levels in native Phragmites sites and native stem density, nutrient concentrations, and denitrification rates. Surprisingly, we found no significant relationships between exotic stem density or water level and measured variables. These results suggest 1) the native strain may have important ecosystem effects that had only been documented for exotic Phragmites, and 2) abiotic drivers such as water level may have mediated this outcome. Further work is needed to determine if the stem density gradients were a consequence, rather than a cause, of pre-existing gradients of abiotic factors.History and conservation of Tunisia's largest freshwater wetland: Garâa Sejenane
de Maya Rouissi, Serge D. Muller, Imtinen Ben Haj Jilani, Zeineb GHRABI-GAMMAR, Laure Paradis, Marion Bottollier-Curtet, Eric Gerbaud, Amina Daoud-Bouattour
In Review of Palaeobotany and Palynology, https://doi.org/10.1016/j.revpalbo.2018.06.008 (6/2018)
En ligne : linkinghub.elsevier.com[...]
The Garâa Sejenane is an ancient lake in northern Tunisia that currently houses a mosaic of temporary wetlands. Comparison of modern pollen data and field vegetation surveys shows both a weak regional pollen signal and the homogenization of pollen assemblages at the scale of the garâa. Despite a hiatus between 19,000 and 2230 cal. BP, fossil pollen analyses provide the first Tunisian LGM record and attest to the ancient origin of the lake, which housed some taxa still present locally in the 1950s. The originality of the Pleniglacial surrounding landscape dominated by a juniper steppe contrasted with to the mountain conifer forests in Kroumiria. Lastly, analyses of aerial photographs (1948, 1962, 1984), recent satellite photographs and previous botanical descriptions reveal that the lake has been drying since 1960 because of important anthropogenic activities (drainage, groundwater pumping, cultivation, grazing…). These disturbances have generated profound changes in hydrophytic plant communities (fragmentation, diversity loss, introduction of invasive species…) that are likely to threaten their long-term survival.
de Mouna Benradia, Mohcen Menaa, K Guellati, Mohamed-Cherif Maazi, Zihad Bouslama, Moussa Houhamdi
In Bulletin de la Société zoologique de France, 143(3) (Mai 2018), 146-168
During four years of study (September 2011-August 2015), the rich diversity of the wetland avifauna of the wilaya of Souk-Ahras was studied, resulting in records of
thirteen species of Anatidae and one species of Rallidae, the Common coot Fulica atra,
which showed a regular presence throughout the study period. Observations on the seasonal evolution of Anatidae populations and those of the Coot at the study sites made it possible to define the status and phenology of all the species. The wetlands in Souk Ahras area were found to be exploited by the birds for overwintering, as a waypoint during the migrations and for reproduction. A total of ten migratory species was counted and four other species are sedentary breeders (the White-headed Duck, Oxyura leucocephala, the Ferruginous Duck, Aythya nyroca, the Mallard, Anas platyrhynchos and the Common coot, Fulica atra). The species-richness presents inter-site and interyear variations.
In addition to hosting a significant proportion of wintering and breeding birds
for a large number of species, the numbers at some wetlands meet the criteria for Ramsar designation (Criterion 6) for one wintering and one nesting waterbird species, namely the Ferruginous duck Aythya nyroca and the White-headed duck Oxyura leucocephala. Moreover, the monitoring of this avifauna has shown that these environments are frequented by four species with an unfavorable protection status nationally and internationally: the Ferruginous duck, Aythya nyroca, White-headed duck, Oxyura leucocephala, Marbled Teal, Marmaronetta angustirostris, and the Shelduck, Tadorna tadorna.
The impact of anthropogenic factors on the waterbird populations at SoukAhras
wilaya was very evident during the four seasons. Despite these negative impacts,
the sites of this area still present a great ornithological value.Wetlands In a Changing Climate: Science, Policy and Management
de William R. Moomaw, G. L. Chmura, Gillian T. Davies, C. M. Finlayson, B. A. Middleton, Susan M. Natali, J. E. Perry, N. Roulet, Ariana E. Sutton-Grier
In Wetlands, Online (April 2018), 1-23
En ligne : link.springer.com[...]
Part 1 of this review synthesizes recent research on status and climate vulnerability of freshwater and saltwater wetlands, and their contribution to addressing climate change (carbon cycle, adaptation, resilience). Peatlands and vegetated coastal wetlands are among the most carbon rich sinks on the planet sequestering approximately as much carbon as do global forest ecosystems. Estimates of the consequences of rising temperature on current wetland carbon storage and future carbon sequestration potential are summarized. We also demonstrate the need to prevent drying of wetlands and thawing of permafrost by disturbances and rising temperatures to protect wetland carbon stores and climate adaptation/resiliency ecosystem services. Preventing further wetland loss is found to be important in limiting future emissions to meet climate goals, but is seldom considered. In Part 2, the paper explores the policy and management realm from international to national, subnational and local levels to identify strategies and policies reflecting an integrated understanding of both wetland and climate change science. Specific recommendations are made to capture synergies between wetlands and carbon cycle management, adaptation and resiliency to further enable researchers, policy makers and practitioners to protect wetland carbon and climate adaptation/resiliency ecosystem services.Mapping Mediterranean Wetlands With Remote Sensing: A Good-Looking Map Is Not Always a Good Map
de Christian Perennou, Anis Guelmami, Marc Paganini, Petra Philipson, Brigitte Poulin, Adrian Strauch, Christian Tottrup, John Truckenbrodt, Ilse R. Geijzendorffer, David A. Bohan, et al.
In Advances in Ecological Research, 58(1) (2018), 243-277
En ligne : www.sciencedirect.com[...]
Wetlands are a key habitat within the Mediterranean biodiversity hotspot and provide important ecosystem services for human well-being. Remote sensing (RS) has significantly boosted our ability to monitor changes in Mediterranean wetlands, especially in areas where little information is being collected. However, its application to wetlands has sometimes been flawed with uncertainties and unrecognized errors, to a large extent due to the inherent and specific ecological characteristics of Mediterranean wetlands. We present here an overview of the state of the art on RS techniques for mapping and monitoring Mediterranean wetlands, and the remaining challenges: delineating and separating wetland habitat types; mapping water dynamics inside wetlands; and detecting actual wetland trends over time in a context of high, natural variability. The most important lessons learned are that ecologists’ knowledge need to be integrated with RS expertise to achieve a valuable monitoring approach of these ecosystems.First study on waterbirds wintering at the southern Mekhada marsh (North-East Algerian Ramsar site)
de Bourafa Yamen, Boucheker Abdennour, Seddik Sihem, Maazi Mohamed El Cherif, Houhamdi Moussa
In Ecology, Environment and Conservation, 24(3) (March, 2018), 1123-1130
En ligne : www.univ-soukahras.dz[...]
The phenology of waterbirds was carried out in the south of the Mekhada marsh an important birds area (IBA) in the North-East of Algeria during two wintering seasons (2015-2016 and 2016-2017). We used a Optolyth telescope with 20-80X zoom, to conduct regular censuses of waterbirds in the studied area. In total, 40 species representing 12 families were recorded at this site. In winter, Ducks are well represented (10 species, with a maximum of 26835 and 33875 individuals were counted in January and February through the two wintering periods). The results of ecological indices (Shannon and equitability) and species richness showed an imbalance in the stand of waterbirds dominated by three families (Anatidae, Scolopacidea and Rallidea). We noted an increase in frequentation on the study area among the two wintering seasons (2 test = 360, 12; df = 1; p = 0, 0001). The correspondence factor analysis showed three distinct periods representing (The beginning, middle and end of wintering season). This preliminary results, of wintering waterbirds monitoring showed that the Mekhada marsh seems to offer ideal conditions for wintering and resting migratory waterbirds.
de R. Mezbour, A. Reggam, M. C. Maazi, M. Houhamdi
In Journal of Materials and Environmental Sciences, 9(3) (2018), 971-979
En ligne : www.jmaterenvironsci.com
The region of EL-Tarf (Extreme East – Algerian) is composed of a variety of Wetlands, Lake of birds is part of this complex. It is an ecosystem of freshwater classified as a Ramsar site in 1999, known for its biodiversity. The water pollution of this ecosystem is a reality and represents a serious environmental problem because on the one hand discharges of domestic wastewater in lake, and secondly the intensive farming at the edges of the lake (cattle, sheep).To protect this aquatic ecosystem it has become essential to make this pollution measurable by the evaluation of the index of organic pollution which is calculated according to the method of Leclercq Maquet (1987), the results show a high organic pollution and also the bacteriological results shows a very important fecal contamination expressed by high rates in total coliforms, fecal coliforms, and fecal streptococci. The Principal Component Analysis (PCA) revealed two gradients the first one reflects the degree of organic pollution while the second describes the metallic pollution of waters in order to give answers to the main causes of pollution.Plankton metacommunities in floodplain wetlands under contrasting hydrological conditions
de Griselda Chaparro, Zsófia Horváth, Inés O'Farrell, Robert Ptacnik, Thomas Hein
In Freshwater Biology, 63(4) (04/2018), 380-391
En ligne : doi.wiley.com[...]
Species diversity is affected by processes operating at multiple spatial scales, although the most relevant scales that contribute to compositional variation and the temporal shifts of the involved mechanisms remain poorly explored. We studied spatial patterns of phytoplankton, rotifers and microcrustacean diversity across scales in a river floodplain system of the Danube in Austria under contrasting hydrological conditions (post-flood versus low water level).
The species turnover between water sections (β2) and between wetlands (β3) was the major components of regional diversity for all studied groups, with species turnover between habitats (β1) as a minor contributor. β1 diversity and β2 diversity were lower than expected by chance in most cases, suggesting that communities are more homogeneous than expected at these scales. β3 diversity was higher than expected by chance in many cases, indicating more distinct communities at the wetland level. Patterns were highly similar under different hydrological conditions, indicating no major immediate effect of flood events.
Local environmental and spatial factors were similarly important in structuring phytoplankton, rotifer and microcrustacean communities in both hydrological conditions. Relevant environmental factors were spatially structured in post-flood conditions especially between sections, suggesting flood-driven homogenisation within the wetlands. Under low water level, spatial structuring of environment decreased and pure environmental factors gained relevance for phytoplankton and rotifers.
Our results suggest that although β2 diversity between water sections is a major component of regional diversity, long-term spatial processes responding to connectivity across the wetland structure phytoplankton, rotifer and microcrustacean communities. Aquatic sections within the limited spatial extent of the remaining floodplain areas appear more homogeneous than expected probably due to flood recurrence over the years.
These results highlight that adequate planning of restoration and conservation strategies of floodplain wetlands should consider environmental heterogeneity together with long-term spatial processes.
de Tom Pinceel, Falko Buschke, Margo Weckx, Luc Brendonck, Bram Vanschoenwinkel
In BMC Ecology, 18 (January 24, 2018), 2
En ligne : doi.org[...]
Higher temperatures and increased environmental variability under climate change could jeopardize the persistence of species. Organisms that rely on short windows of rainfall to complete their life-cycles, like desert annual plants or temporary pool animals, may be particularly at risk. Although some could tolerate environmental changes by building-up banks of propagules (seeds or eggs) that buffer against catastrophes, climate change will threaten this resilience mechanism if higher temperatures reduce propagule survival. Using a crustacean model species from temporary waters, we quantified experimentally the survival and dormancy of propagules under anticipated climate change and used these demographic parameters to simulate long term population dynamics.L’hivernage de la Grue cendrée Grus grus en Camargue : historique et statut récent
de Yves Kayser, Michel Gauthier-Clerc, Thomas Blanchon, Philippe Vandewalle, Silke Befeld, Jérémiah Petit, Rémi Tiné, Amine Flitti, Jocelyn Champagnon
In Ornithos, 25(1) (2018), 4-13
The Common Crane was a rare wintering bird in The Camargue until the late 1990s and early 2000s. From the winter of 2003- 2004, wintering numbers have steadily increased to more than 14,000 individuals by January 2017, spread over a dozen roosts. The frequented roosts are large open areas, usually made up of freshwater marshes. During the winter season, cranes mainly feed on rice stubble. Other food resources such as winter wheat are used to a lesser extent. Some birds do not hesitate to fly further up to 30 km to fetch food. Fifty ringed birds were controlled between 2013 and 2017, the majority (89 %) of them originated from Finland. It seems that the cranes use two migration routes to The Camargue : one central European routeway and another one possibly passing through western France, which could indicate a loop migration.Successful conservation of global waterbird populations depends on effective governance
de Tatsuya Amano, Tamás Székely, Brody Sandel, Szabolcs Nagy, Taej Mundkur, Tom Langendoen, Daniel Blanco, Candan U. Soykan, William J. Sutherland
In Nature, 553(7687) (December, 2017), 199-202
En ligne : www.nature.com[...]
Understanding global patterns of biodiversity change is crucial for conservation research, policies and practices. However, for most ecosystems, the lack of systematically collected data at a global level limits our understanding of biodiversity changes and their local-scale drivers. Here we address this challenge by focusing on wetlands, which are among the most biodiverse and productive of any environments1,2 and which provide essential ecosystem services3,4, but are also amongst the most seriously threatened ecosystems3,5. Using birds as an indicator taxon of wetland biodiversity, we model time-series abundance data for 461 waterbird species at 25,769 survey sites across the globe. We show that the strongest predictor of changes in waterbird abundance, and of conservation efforts having beneficial effects, is the effective governance of a country. In areas in which governance is on average less effective, such as western and central Asia, sub-Saharan Africa and South America, waterbird declines are particularly pronounced; a higher protected area coverage of wetland environments facilitates waterbird increases, but only in countries with more effective governance. Our findings highlight that sociopolitical instability can lead to biodiversity loss and undermine the benefit of existing conservation efforts, such as the expansion of protected area coverage. Furthermore, data deficiencies in areas with less effective governance could lead to underestimations of the extent of the current biodiversity crisis.Isoëto-Nanojuncetea in Puglia (S-Italy): first phytosociological survey
de P. Ernandes, D. Gigante, L. Beccarisi, S. Marchiori, R. Venanzoni, V. Zuccarello
In Plant Sociology, 54(2) (December 2017), 23-36
En ligne : www.scienzadellavegetazione.it[...]
Mediterranean temporary ponds (MTP) are considered among the most interesting habitats in the Mediterranean bioclimatic region due to the range of rare and threatened taxa they host. Their ephemeral vegetation presents a particular floristic composition, adapted to unstable ecological conditions due to the alternation between flood and drought. Indeed, these amphibian plant species are established on soils flooded in winter and dry since early summer. The water depth and inundation period determine the plant communities distribution. The vegetation can be referred to the class Isoëto-Nanojuncetea, that has a wide distribution and is represented in the study area by two orders: Isoëtetalia, Mediterranean and W-European, with spring and early summer bloom, and Nanocyperetalia, C-European, with late summer and autumn bloom. This study describes for the first time the Isoëto-Nanojuncetea plant communities in Puglia Region, in SE-Italy, where the class distribution was unknown up to now. The here adopted syntaxonomical scheme is consistent with numerical analysis, resulting in homogenous floristic and ecological communities that correspond to syntaxa at association level. The phytosociological approach to the interpretation and management of vegetation and biodiversity has been recently revived by the habitat-type classification adopted by the European 92/43/EEC “Habitat” Directive in its Annex I. The here considered plant commu- nities belong to the priority habitat “3170* Mediterranean temporary ponds”. Aiming to typify them, 170 surveys were carried out in temporary pools over a wide area resulting from a detailed survey that took into account the whole Puglia territory. These complexes of vegetation are very sensitive to the environmental and anthropic disturbance, so they might be good bioindicators with high value for habitat monitoring and conservation.
Key words: amphibious vegetation, biodiversity, “Habitat” Directive 92/43/EEC, Mediterranean, Natura 2000, priority habitat, temporary wetlands.Milieux humides et sociétés en Provence littoral à l'époque romaine. Un essai d'écologie historique
de Philippe Leveau
In Provence historique, 57(262) (2017), 313-350
Etangs, marais et deltas en Provence
550 pages
de Aurélien Allouche, Delphine Nicolas
In Provence historique, 57(262) (2017), 471-494Global Wetland Datasets: a Review
de Shengjie Hu, Zhenguo Niu, Yanfen Chen
In Wetlands, 37(5) (10/2017), 807-817
En ligne : link.springer.com[...]
Accurate wetland datasets are indispensable for generating polices on wetland conservation and appropriate land uses, global climate change studies, and biodiversity conservation. Although increasing numbers of global wetland-related datasets have been established, the extensive disagreements among these datasets are prominent. In particular, estimates of global wetland area range from 0.54 to 21.26 million km2 and the class-specific spatial consistency of wetlands is less than 1%. The different definitions of ‘wetland’ and the intrinsic features of wetlands contribute to this extensive inconsistency. Given the various requirements of wetland-oriented data products, it is important to conduct comprehensive wetland mapping at global scale. The Ramsar wetland definition is recommended and a hierarchical and flexible structure of wetland classification system is preferred for future global wetland datasets. Time-series satellite imagery at 250–1000 m spatial resolution is preferred to characterize wetland dynamics by combination of passive/active SAR data and other ancillary data, such as topography, climate, and soil data. The classification tree method for classification of massive satellite imagery and big-data technology for sample datasets are promising for the enhancement of wetland map product accuracy.Substantial decline of Northern European peatland bird populations: Consequences of drainage
de Sara Fraixedas, Andreas Linden, Kalle Meller, Åke Lindström, Oskars Keišs, John Atle Kålås, Magne Husby, Agu Leivits, Meelis Leivits, Aleksi Lehikoinen
In Biological Conservation, 214 (October 2017), 223-232
En ligne : linkinghub.elsevier.com[...]
Northern European peatlands are important habitats for biological conservation because they support rich biodiversity and unique species compositions. However, historical management of peatland habitats has had negative consequences for biodiversity and their degradation remains a major conservation concern. Despite increasing awareness of the conservation value of peatlands, the statuses and ecological requirements of peatland species have remained largely understudied. Here, we first analysed temporal trends of Northern European peatland birds to document the status of their populations using bird data from five different countries. Second, we used Finnish monitoring data to assess habitat preferences of peatland bird species, hence helping to target conservation to the most relevant habitat types. There was a general decline of 40% in Northern European peatland bird population sizes in 1981–2014 (speed of decline 1.5%/year) largely driven by Finland, where populations declined almost 50% (2.0% annual decline). In Sweden and Norway, peatland bird populations declined by 20% during 1997–2014 (1.0% annual decline). In contrast, southern populations in Estonia and Latvia, where the majority of open peatlands are protected, showed a 40% increase during 1981–2014 (1.0% annual increase). The most important habitat characteristics preferred by common peatland species in Finland were openness and low tree height, while wetness proved to be an important feature for waders. Drainage of peatlands had clear negative effects on the densities of many species, with the only exception of rustic bunting, which specializes on edge habitats. Our findings call for more effective conservation actions in Northern European peatland habitats, especially in Finland where peatland drainage represents a major threat to biodiversity.
de Matthieu Guillemain, Richard Hearn
In Biodiversity and conservation, 26(10) (2017/09/01), 2347-2360
En ligne : link.springer.com[...]
The geographic range of many migratory bird populations is shifting in response to climate change. Protected areas play a major role in the conservation of many such species, yet these reserves are static so a geographic mismatch between the habitat needs of the birds and the network of protected areas may gradually appear. Ducks in the Western Palearctic are most likely to shift their distribution northwards and eastwards in response to climate change, so we evaluated whether the mean protection level of the most critical sites for ducks shows any latitudinal or longitudinal trend. From the description of site protection level in the Critical Site Network database (little/none to full protection) a site protection score was computed, ranging from 0 (little/none) to 3 (full protection). More northern sites had greater mean protection scores. Conversely, a negative longitudinal gradient was identified, with much poorer protection of critical duck sites in Eastern Europe, the Middle East and Central Asia. This is where duck populations are currently the largest, and among the areas where duck populations are expected to increase in the future following climate change, although currently a relatively high proportion also show decreasing population trends. The site protection score was also greatest, on average, in member states of the European Union rather than in other European countries, suggesting EU directives have been successful at improving the level of protection of the most important wetlands for ducks. Although ducks could benefit from further conservation of the sites they use anywhere within their geographic range, and there is room for improvement of protection score in all areas, this study suggests that future site protection efforts should be internationally coordinated, and first targeted at sites east of the Mediterranean shore.
de Mohammed El Madihi, Laïla Rhazi, Maarten Van den Broeck, Mouhssine Rhazi, Aline Waterkeyn, Er-riyahi Saber, Siham Bouahim, Moustapha Arahou, Abdelmajid Zouahri, Anis Guelmami, et al.
In Plant Ecology & Diversity, 10(1) (2017-07-24), 1-19
En ligne : www.tandfonline.com[...]
Background: Temporary ponds, an abundant habitat in the Maghreb region and notably in Morocco, have a high conservation value. However, they are mainly known from the north of the country.
Aims: The aim of this work was to characterise the vegetation of Moroccan temporary ponds along a combined gradient of latitude and anthropogenic pressure.
Methods: Eighty-five ponds distributed along a north–south gradient of 750 km were sampled. For each pond, all vegetation was surveyed (flooded and dry parts) and the local abiotic characteristics were measured during two successive hydrological cycles. The prevailing anthropogenic pressures were also identified and were attributed an impact score.
Results: Eighty-one characteristic pond species (including 17 rare species) were recorded, with several new distribution data in the southern part of the latitudinal gradient. Plant communities were related to climatic and anthropogenic factors, but mostly to local factors, such as maximum water depth and soil pH. The northern ponds (wettest macroclimate) were rich in characteristic species and rare species, while the southern (driest macroclimate) ponds were more species poor.
Conclusions: In addition to the direct impact of increasing human activity, a further reduction of the floristic richness of temporary ponds is expected due to climatic changes. This is particularly the case for characteristic species which have a high conservation value.
L'inondation hivernale des rizières: vers une gestion favorable aux canards comme aux agriculteurs
de Claire Agnès Pernollet, Matthieu Guillemain, Michel Gauthier-Clerc
In Faune sauvage, 314 (2017), 37-43
En ligne : www.tourduvalat.org[...]Policy considerations for managing wetlands under a changing climate
de C. M. Finlayson, S. J. Capon, D. Rissik, J. Pittock, G. Fisk, N. C. Davidson, K. A. Bodmin, P. Papas, H. A. Robertson, M. Schallenberg, et al.
In Marine and Freshwater Research, March 2017 (2017/03/03), 13 p.
En ligne : www.publish.csiro.au[...]
Drawing on the experience and lessons of wetland researchers and managers in Australia and New Zealand, we examined the implications of climate change for wetland policy and management, and identified potential adaptation responses and the information needed to support these. First, we considered wetland vulnerability to climate change, focusing on wetland exposure and sensitivity. We then outlined the existing policy context for dealing with climate change, with an emphasis on the Ramsar Convention on Wetlands. We then considered how the objectives and targets for wetland management can be set in the face of climate change, how management can be adapted to climate change given the uncertainties involved, and how we can monitor and evaluate wetland condition in the face of climate change. We concluded with a set of principles to guide adaptation of wetland conservation and management policy to climate change.Mangrove Reed Warbler (Acrocephalus scirpaceus avicenniae) at the Red Sea in Egypt
de Jens Hering, Elmar Fuchs, Wieland Heim, Hans-Jürgen Eilts, Peter Barthel, Hans Winckler
In African Bird Club, 24(1) (2017/03/01), 49-62
En ligne : www.africanbirdclub.org[...]
In April 2012, we discovered Mangrove Reed Warbler Acrocephalus scirpaceus avicenniae at the Red Sea coast near Hamata, in southern Egypt. This was the first record of this subspecies for the Western Palearctic. During additional surveys in subsequent years, we also observed breeding Mangrove Reed Warblers. In addition to morphological and genetic data, we collected information on breeding habitat, breeding biology (including the first description of salt-preserved nests), abundance, other species present and population threats. In July–August 2015 we found A. s. avicenniae in the mangroves of Shura Al-Rowaisseya, on the Sinai Peninsula. Further research on this taxon is recommended to clarify its distribution, breeding ecology and migratory status.
de Sidi Imad Cherkaoui, Slaheddine Selmi, Saâd Hanane
In Ecological Research, 32 (2017/02/06), 1-11
En ligne : link.springer.com[...]
Conservation of Anatidae in North Africa is hindered by lack of information concerning population size, population trends, and species-habitat relationships. In this work, we used a 2-year survey data in 25 wetlands distributed throughout Morocco to model duck spatial distribution and to assess the relevance of a set of environmental and anthropogenic factors in predicting site occupancy, by means of Generalized Linear Mixed Models (GLMM). Mallards and Ferruginous ducks were the most commonly detected species, whereas White-Headed Ducks and Common Pochards were the least detected ones. An inter-annual variation in site occupancy was recorded for Ruddy Shelducks, Red-Crested Pochards and White-Headed Ducks. Geographical location (measured mainly as distance to the coastline and altitude) was the major predictor of the occurrence probability of Ruddy Shelducks, Marbled Teals and Red-Crested Pochards, while human presence and habitat features were the most relevant factors in shaping Mallard’s distribution. However, none of the considered environmental and anthropogenic factors explained the distribution patterns of the Ferruginous Duck, Common Pochard and Gadwall. The results of this study clearly show that there are still gaps in our knowledge on factors driving wetland occupancy by breeding Anatidae in Morocco. The pursuit of the investigations, while considering other explanatory factors such as water quality (limnological data), diet, predation, and conservation status, is of great importance to more profoundly understand the dynamics of Moroccan duck populations.A literature review of Algerian salt lakes: values, threats and implications
de Fatma Demnati, Boujéma Samraoui, Farid Allache, Alain Sandoz, Lisa Ernoul
In Environmental Earth Sciences, 76(3) (2017/02/01), 127
En ligne : link.springer.com[...]
Chotts are salt lakes located in the arid regions of Northern Africa. These unique wetlands are recognized for their role in the migration and breeding of waterbirds and economic values generated from mineral extraction, agriculture and tourist activities. Despite their importance for flora and fauna biodiversity, they continue to face important threats due to human activities. This article consolidates a literature review of Algerian chotts from global to local importance. An in-depth view demonstrates the changes in land use of two large chotts in the southeastern region of Algeria: Chotts Merouane and Melghir. Land use images highlight a net expansion of agricultural lands, a decrease in grazing area around the lakes and a decrease of salt lake surface area. The local focus highlights the threats and changes of Algerian and Northern African chotts and proposes some perspectives for the future.
de M. S. Sayoud, H. Salhi, B. Chalabi, A. Allali, M. Dakki, A. Qninba, M. A. El Agbani, Hichem Azafzaf, Claudia Feltrup‐Azafzaf, H. Dlensi, et al.
In Biological Conservation, 206 (février 2017), 11-20
En ligne : www.sciencedirect.com[...]
The International Waterbird Census (IWC) is one of the most widespread biodiversity monitoring programs, assessing waterbird populations in the framework of several international agreements including the African-Eurasian migratory Waterbirds Agreement and the Ramsar Convention. In 2013, the IWC was coordinated for the first time across the whole of North Africa with the aim of developing recommendations for methodological improvements to current design in North Africa, as well as to update the conservation status of certain waterbird populations and wetlands of international importance. We show that coordinating the IWC across all five North African countries significantly improves knowledge of waterbird population sizes and distribution and confirmed that current North African Ramsar wetlands perform well in conserving waterbirds. Nevertheless, biodiversity conservation could potentially be further enhanced by designating additional Ramsar sites, which this study contributes to identifying. We show that reducing sampling effort by half over the entire region would have been sufficient to cover 100% of the species richness of wintering waterbirds recorded and > 98% of the total abundance. Finally, we show that larger wetlands are insufficiently sampled. These findings call for revised sampling design in a coordinated, region-wide framework. The maintenance, optimization and reinforcement of the IWC program over time on a regional scale, with the collected data made available in a shared database, seems essential in order to make appropriate conservation decisions for waterbirds and wetlands in the future. Adding a temporal dimension to these analyses will be critical to confirm the patterns observed in the 2013 census.Seed density and waterfowl use of rice fields in Camargue, France
de Claire Agnès Pernollet, Francois Cavallo, David Simpson, Michel Gauthier-Clerc, Matthieu Guillemain
In The Journal of Wildlife Management, 81(1) (Jan. 2017), 96-111
En ligne : onlinelibrary.wiley.com[...]
European rice fields provide potential nocturnal foraging habitat to waterfowl during winter. Agricultural practices may influence seed density and accessibility, thereby influencing the extent to which ducks use this managed habitat. To assess the potential influence of post-harvest stubble-management practices (i.e., flooding, burning, chopping, disking, plowing, and their combinations) on waste rice and weeds, and to evaluate the link of the latter 2 with nocturnal duck abundance, we conducted an experiment in rice fields of the Camargue, France. We assessed the density of available seeds 3 times across the winter, from harvest in late October to departure of the wintering ducks in early February, over 2 winters (2012–2013, 2013–2014). We monitored nocturnal duck use of the fields during the second year. Initial post-harvest rice and weed seed densities were positively correlated and highly variable. Mean seed density was not dependent on straw management procedure (i.e., burning, chopping, disking). Average rice density decreased by 89% and weed seed density by 69% between harvest and late winter. Seed depletion rate was dependent on initial seed density, and was greatest in plowed fields for rice. Winter flooding did not significantly affect seed depletion rate but was the main determinant of nocturnal duck use of the fields. Duck numbers were lower in burned fields than in chopped or disked fields. One hectare of rice field could support an average of 43 mallard (Anas platyrhynchos)-sized ducks/day for the entire wintering season (i.e., 5,202 duck-energy days/ha) given initial post-harvest seed densities. Harvested rice fields have a great potential as nocturnal foraging habitat for wintering ducks in the Camargue. Plowing should be avoided and flooding promoted to better allow ducks to use these fields.
de Salah Telailia, Lamia Boutabia, Mohamed Dhaya El-Hak Khemis, Ali Elafri, Nawel Djebbari
In Ekológia (Bratislava), 36(2) (2017-01-27)
En ligne : www.degruyter.com[...]
Recently, Mediterranean coastal lagoons have raised considerable environmental concerns. Long-term studies of seasonal changes in waterbird assemblages are therefore extremely important in terms of ecological relevance and conservation of these sensitive ecosystems. a n ornithological survey of four years was carried out in a typical costal wetland (El Mellah lagoon) of northeastern Algeria. intra-seasonal comparison of waterbird assemblages (diversity indices) demonstrates clear changes between the wintering and the breeding periods. i t seems that the first one was rich in term of species number than the second season (43 against 24). i n contrast, the breeding seasons were more equilibrate (high values of Simpson, Shannon and evenness index). additionally, curves in the diversity/dominance diagram revealed that both wintering and breeding assemblages share the same characteristics of community structure, few dominant species (with intermediate relative abundance) and many rare species with the relative abundance lower than 0.1. invertebrates (25 species) and piscivorous (11 species) are the most abundant guilds over the four years of study (no significant differences among years have been calculated). The marked decline in bird species diversity recorded in this study (in comparison with previous studies) is mainly due to salinity oscillations (due to aquaculture activities) and may be of concern to wetland managers and it might be useful to provide some guidelines about the characteristics that coastal lagoons have to follow in the construction process to enhance the biodiversity.
Best LIFE nature projects, 2015 (2017)
de European Commission, Directorate-General for the Environment
Luxembourg : Office of Official Publications of the European Communities, 2017, 72
En ligne : ec.europa.eu[...]
This Best LIFE-Nature / Information Projects aims to recognise the best projects that completed their work during the reference period 2015. The following projects (in no particular order) have been selected by the Member States as "Best of the Best" LIFE Nature / Information projects that finished in 2015:
• Spain: Building capacity to tackle illegal poisoning of wildlife
• Finland: Restoring vital peatland habitats
• Hungary: Establishing a seedbank f or the long-term conservation of wild plants
• Poland: Harnessing biomass for bird conservation
• Cyprus: Restoring priority juniper habitats
• Poland: Introducing ancient forests to an audience of millions
• Austria: Bringing fish species back to the Danube
• Germany: New ways of conserving traditional orchards
• Bulgaria: Conserving priority bird species in the Bourgas lakes
• Bulgaria: Aiding the recovery of Europe’s large Falco cherrug
• Bulgaria: Restoring riparian habitats and tackling invasive alien species
• France: Restoring rare alluvial forest
• Poland: Enhancing lesser spotted eagle populations
• United Kingdom: Revitalising a degraded bog landscape
• France: Bird conservation in the outermost regions
• Hungary: Conserving the Saker falcon
• Italy: Developing coordinated protection measures for Apennine chamois
• Poland: Protecting and reviving the white stork population
• Poland: Restoring inland dunes with grasslands
• Poland: Optimising habitats for rare wetland birds
• Slovenia: Rehabilitating damaged wetlands
• Slovakia: Protecting the lesser spotted eagle
• Spain: Ensuring the health of mountain pastures
• Italy: Removing an alien threat to the white-clawed crayfish
• Spain: Crafting strategies for land stewardship across Europe
• Slovenia: Demonstrating the importance of freshwater biodiversity
• United Kingdom: Supporting the Natura 2000 network
Suivre les services récréatifs et éducatifs des zones humides méditerrannéennes
de L. Chazee, M. Réquier-Desjardins, Wided Khechimi
In Zones Humides Infos, 92-93 (3ème-4ème trim. 2016), 28
En ligne : www.snpn.com[...]High-resolution mapping of global surface water and its long-term changes
de Jean-François Pekel, Andrew Cottam, Noel Gorelick, Alan S. Belward
In Nature, 540(7633) (December, 2016), 418-422
En ligne : www.nature.com[...]
The location and persistence of surface water (inland and coastal) is both affected by climate and human activity and affects climate, biological diversity and human wellbeing. Global data sets documenting surface water location and seasonality have been produced from inventories and national descriptions, statistical extrapolation of regional data8 and satellite imagery, but measuring long-term changes at high resolution remains a challenge. Here, using three million Landsat satellite images13, we quantify changes in global surface water over the past 32 years at 30-metre resolution. We record the months and years when water was present, where occurrence changed and what form changes took in terms of seasonality and persistence. Between 1984 and 2015 permanent surface water has disappeared from an area of almost 90,000 square kilometres, roughly equivalent to that of Lake Superior, though new permanent bodies of surface water covering 184,000 square kilometres have formed elsewhere. All continental regions show a net increase in permanent water, except Oceania, which has a fractional (one per cent) net loss. Much of the increase is from reservoir filling, although climate change14 is also implicated. Loss is more geographically concentrated than gain. Over 70 per cent of global net permanent water loss occurred in the Middle East and Central Asia, linked to drought and human actions including river diversion or damming and unregulated withdrawal15,16. Losses in Australia17 and the USA18 linked to long-term droughts are also evident. This globally consistent, validated data set shows that impacts of climate change and climate oscillations on surface water occurrence can be measured and that evidence can be gathered to show how surface water is altered by human activities. We anticipate that this freely available data will improve the modelling of surface forcing, provide evidence of state and change in wetland ecotones (the transition areas between biomes), and inform water-management decision-making.
de Coralie Beltrame, Christian Perennou, Anis Guelmami
In Méditerranée, 125 (2015), 97-111
Les zones humides méditerranéennes dans leur ensemble, écosystèmes de haute valeur pour la biodiversité, ont perdu environ 50 % de leur superficie au cours du xx e siècle. Par ailleurs, le littoral méditerranéen est soumis à de fortes pressions dues à l’urbanisation, au tourisme mais aussi au développement d ’infrastructures industrielles et de transport. Il y a donc dans les zones humides littorales méditerranéennes une convergence d’enjeux écologiques, sociaux et économiques. L’évolution de l’occupation du sol a été caractérisée dans 214 d’entre elles entre 1975 et 2005. En leur sein, la superficie des habitats humides naturels a diminué de 10 % en 30 ans, soit une perte de 1329 km². À l’inverse, les habitats humides d’origine anthropique ont augmenté de 105 %, c’est -à-dire un gain de 854 km². Pendant cette période, la principale pression directe sur les habitats humides naturels a été l’agriculture puisque 71 % des habitats humides perdus l’ont été au profit des milieux agricoles. L’urbanisation a eu un impact direct moindre mais elle a entrainé la conversion des terres agricoles périurbaines, qui se sont report ées vers les habitats naturels périphériques. Mots-clés : Méditerranée, zone humide littorale, SIG, télédétection, artificialisation, occupation du sol, pression agricole, pression urbaine / Overall, Mediterranean wetlands are very important ecosystems for biodiversity. Approximately half their area was lost during the 20 th century. The Mediterranean coast is also under heavy pressure due to urbanization, tourism and development of industrial and transport infrastructures. The Mediterranean coastal wetlands thus represent a convergence point of ecological, human and economic issues. Changes in land cover between 1975 and 2005 were characterized in 214 of them. The area of natural wetland habitats decreased by 10 % in 30 years, i.e. a loss of 1329 km². At the same time, artificial wetland habitats increased by 105 %, i.e. a gain of 854 km². The main direct pressure on natural wetland habitats was agriculture, with 71 % of them converted into agricultural areas. Urbanization had less direct impact but largely affected agricultural areas, which in turn were displaced onto natural habitats.The role of waterbirds in the dispersal of aquatic alien and invasive species
de Chevonne Reynolds, Nelson A. F. Miranda, Graeme S. Cumming
In Diversity and Distributions, 21(7) (juillet 1, 2015), 744-754
En ligne : onlinelibrary.wiley.com[...]
Aim
To review existing literature on the ability of waterbirds to spread aquatic alien and invasive species, and to assess the relevance of bird-mediated dispersal for the conservation of freshwater ecosystems.
Location
Global.
Methods
Literature Review.
Results
A systematic review of the literature revealed that quantitative studies investigating dispersal of alien organisms by waterbirds are rare (n = 14). Most studies citing waterbird dispersal rely on anecdotes or inferences from morphological dispersal syndromes. However, evidence from each stage of dispersal (i.e. emigration, transport and immigration) shows that waterbirds can carry alien plants and invertebrates internally and externally; transport them between water bodies at a variety of spatial scales; and deposit viable propagules in sites suited to aquatic invasive species.
Main conclusions
Our review suggests that waterbirds can and do act as important dispersal vectors for freshwater invasive species. Further experimental and field based research on the numbers and viability of moved alien propagules, and the roles of different species in the bird community, is needed. Furthermore, consideration of the spatially explicit manner in which birds move is imperative to understanding invasive spread. Populations of alien aquatic species in seemingly isolated wetlands can no longer be considered contained if they are able to be spread through waterbird-mediated dispersal, and containment measures must recognize such opportunities for further spread. Changing waterbird movement patterns, driven by climate and land use change, further add to the challenge of managing invasive species and offers an interesting opportunity for future research. The study of waterbird-mediated dispersal of aquatic alien invasive species provides insights not only into species invasions, but more generally into movement ecology, population ecology and biogeography.
de Houston C. Chandler, Andrew L. Rypel, Yan Jiao, Carola A. Haas, Thomas A. Gorman
In PLOS ONE, 11(2) (24 févr. 2016), e0150169
En ligne : journals.plos.org[...]
The hydroperiod of ephemeral wetlands is often the most important characteristic determining amphibian breeding success, especially for species with long development times. In mesic and wet pine flatwoods of the southeastern United States, ephemeral wetlands were a common landscape feature. Reticulated flatwoods salamanders ( Ambystoma bishopi ), a federally endangered species, depend exclusively on ephemeral wetlands and require at least 11 weeks to successfully metamorphose into terrestrial adults. We empirically modeled hydroperiod of 17 A . bishopi breeding wetlands by combining downscaled historical climate-model data with a recent 9-year record (2006–2014) of observed water levels. Empirical models were subsequently used to reconstruct wetland hydrologic conditions from 1896–2014 using the downscaled historical climate datasets. Reconstructed hydroperiods for the 17 wetlands were highly variable through time but were frequently unfavorable for A . bishopi reproduction (e.g., only 61% of years, using a conservative estimate of development time [12 weeks], were conducive to larval development and metamorphosis). Using change-point analysis, we identified significant shifts in average hydroperiod over the last century in all 17 wetlands. Mean hydroperiods were shorter in recent years than at any other point since 1896, and thus less suitable for A . bishopi reproduction. We suggest that climate change will continue to impact the reproductive success of flatwoods salamanders and other ephemeral wetland breeders by reducing the number of years these wetlands have suitable hydroperiods. Consequently, we emphasize the importance of conservation and management for mitigating other forms of habitat degradation, especially maintenance of high quality breeding sites where reproduction can occur during appropriate environmental conditions.
de José L. Espinar, Ricardo Díaz-Delgado, Miguel A. Bravo, Montserrat Vilà
In Aquatic Invasions, 10 (2015)
En ligne : digital.csic.es[...]
© 2015 The Author(s). Unravelling how a multiplicity of global change factors might influence the expansion of alien plants is a major goal of invasion biology. We explored the association of climatic conditions (i.e. annual rainfall and average minimum temperature during the coldest months) and water quality (orthophosphate, nitrate concentrations and electrical conductivity), with blooms of the invasive fern Azolla filiculoides Lam. in the Doñana marshland (SW Spain), one of the most extensive wetlands in Europe. Azolla was first detected in Doñana in 2001. Its annual cover has been quantified since then through remote sensing. In the last decade there has been a considerable increase of orthophosphate and yearly fluctuations of nitrate. The first orthophosphate increase coincided with the presence of Azolla in Doñana. Since then, there has been a positive relationship between inter-annual variation in Azolla cover and minimum temperature during the coldest months. Our study shows that the Doñana marshland is facing rapid eutrophication and invasion by Azolla, most notably in years with high temperatures during the winter.
de Thomas Galewski, Vincent Devictor
In PLOS ONE, 11 (Nov. 2016), 1-18
En ligne : journals.plos.org[...]
Many species have suffered large population declines due to the anthropogenic influence on ecosystems. Understanding historical population trends is essential for informing best efforts to preserve species. We propose a new method to reconstruct the past structure of a regional species pool, based on historical naturalist literature. Qualitative information collected from annotated checklists and reports can be relevant to identify major long-term community changes. We reviewed ornithological literature on the Camargue, the largest wetland in France. We reconstructed the entire breeding bird community from 1830 to 2009 and translated historical data into semi-quantitative data. This data permitted a calculation of a Community Commonness Index to measure the average level of abundance of species in a community. The Community Specialization and Community Temperature Indices were used to evaluate the potential long-term impact of land-use and climate changes on the composition of the regional bird species pool. We found a decrease in average abundance and specialization between 1950 and 1989, suggesting that changes in land-use negatively impacted the structure and composition of the local bird community by reducing species abundance and removing habitat-specialists (e.g. Southern Grey Shrike, Greater Short-toed Lark). These results are likely to be linked with a major loss of natural habitats in the Camargue between 1942 and 1984 when natural areas and traditional farmland were converted into intensive cultivated lands. We also found fluctuations among species with high versus low temperature preference. However, long-term effects of climate change on the bird community might be blurred by the impact of land-use changes. Overall, our results contrast with those obtained from well-monitored colonial waterbirds showing long-term increases. Our results plead for a more regular use of historical naturalist data when examining long-term changes in species communities as they allow the establishment of an older temporal point of reference and consideration of species not covered by traditional monitoring schemes. / où l’on présente l’intérêt de la littérature « grise » naturaliste (livres, compte-rendus, rapports de voyage…) pour retracer les variations démographiques historiques d’une population, d’une espèce ou d’une communauté d’espèces.
Ici on s’est intéressé à la communauté d’oiseaux nicheurs de Camargue que l’on a pu reconstruire depuis le début du 19ème siècle jusqu’à nos jours. Il a été possible de coder de manière semi-quantitative l’abondance de toutes les espèces à différents pas de temps. En utilisant cette méthodologie, on observe que la communauté a beaucoup évolué dans le temps avec notamment une diminution de l’abondance spécifique et une perte de spécialisation. En d’autres termes, si 2 espèces sur 3 pouvaient être qualifiées de communes au 19ème siècle, ce n’est plus le cas que pour 1 espèce sur 3 aujourd’hui. La diminution a principalement affecté les espèces spécialistes des milieux agricoles et pâturés (ex : Alouettes, Perdrix rouge, Chevêche, Petit-duc, Tourterelle des bois, Linotte et beaucoup d’autres) tandis que les oiseaux utilisant les milieux humides ont mieux résisté. Ce déclin s’est produit dans les années 1950-1980 à une époque où on enregistre une très forte perte de milieux naturels et semi-naturels en Camargue (pelouses et sansouires en premier lieu) ainsi qu’un changement majeur de l’agriculture camarguaise qui délaisse l’élevage extensif au profit d’une céréaliculture intensive. Cette étude met en évidence un déclin important des oiseaux des milieux agricoles bien antérieur et supérieur au déclin observé depuis 20 ans à travers les programmes de science citoyenne
de Olivier Boutron, Olivier Bertrand, Annie Fiandrino, Patrick Höhener, Alain Sandoz, Yves Chérain, Eric Coulet, Philippe Chauvelon
In Water, 7(11) (October 2016), 5986-6016
En ligne : www.mdpi.com[...]
The spatiotemporal structure of wind-driven circulation patterns and associated water exchanges can drive important bio-hydrodynamic interactions in shallow lagoons. The Vaccarès lagoon system is a complex shallow hydrosystem located in the central part of the Rhône Delta (France). It is internationally recognized as part of a biosphere reserve within the framework of UNESCO’s Man and Biosphere Programme, and as a RAMSAR site. Due to its frequent occurrence in this area, and considering the shallowness of the Vaccarès lagoon system, wind is assumed to play a major role in the hydrodynamic and biological processes. In this study, a hydrodynamic model was developed to investigate the structure of wind-driven circulations in the Vaccarès lagoon system, to provide insights into their role in transport and water exchange processes. The implementation and assessment (calibration and validation) of the model is presented first. Simulations were then performed for two typical steady wind conditions and for one measured unsteady wind event. The results illustrate the influence of the complex geometry of the Vaccarès lagoon system on the wind-driven circulations, and the differences observed between the different sub-lagoons in this system. The differences in wind-induced water exchanges between these sub-lagoons are also discussed.
de Isabel Donoso, Constanti Stefanescu, Alejandro Martinez-Abrain, Anna Traveset
In Oikos, 125(10) (October 2016), 1434-1444
En ligne : onlinelibrary.wiley.com[...]
Although much information has been accumulated on the effects of climate change on particular species worldwide, research aimed at assessing how such change influences biotic interactions from a community-wide perspective is still in its infancy. We contribute to filling in this gap by analyzing a 17-year (1996-2012) dataset that includes records of flower-visitation interactions between 12 butterfly species and 17 plant species in a coastal wetland area in northeastern Iberian Peninsula. We assessed the extent to which temporal asynchronies between plants and adult butterflies are influenced by different climatic variables that affect both plant and insect phenologies. Temperature and degree of aridity at various monthly summaries were used as predictors of the plant-butterfly phenological asynchrony. We identified the seasonal window with the greatest effect on asynchronies for two butterfly generations (spring and summer), and assessed whether the magnitude of asynchrony is associated with the level of butterfly specialization. We used generalized linear mixed models considering a total of 39 plant-butterfly interactions. Average asynchrony was higher in the spring generation and dry conditions during winter lead to decreased temporal overlap with flowers in this butterfly generation, whereas dry conditions in the spring lead to decreased temporal overlap in the summer butterfly generation. The magnitude of the effect was consistently small at the community level (all interactions pooled). Moreover, no clear climatic trend over the study time frame was detected. Finally, specialized and generalized butterflies in their resource use as adults were similarly vulnerable to asynchronies, in contrast to previous predictions of greater mutualistic disruptions in species with narrower niches. We conclude that a least in the Mediterranean region, phenological asynchronies might be more affected by aridity level than by temperature itself, and thus the former can be a key climatic trait to make better predictions in this region.Impacts of climate change on the hydrology of two Natura 2000 sites in Northern Greece
de Ch Doulgeris, D. Papadimos, J. Kapsomenakis
In Regional Environmental Change, 16(7) (2016/10/01), 1941-1950
En ligne : link.springer.com[...]
Greece is included among the most vulnerable regions of Europe by climate change on account of higher temperature and reduced rainfall in areas already facing water scarcity. With respect to wetland systems, many ephemeral ones are expected to disappear and several permanent to shrink due to climate change. As regards two specific wetlands of Greece, the change in hydroperiod of Cheimaditida and Kerkini lakes due to climate change was studied. Lakes’ water balance was simulated using historical climate data and the emission scenarios Α1Β for the period 2020–2050 and Α1Β and Α2 for the period 2070–2100. Future climate scenarios, based on emission scenarios A1B and A2, were provided in the context of the study of Climate Change Impacts Study Committee. The surface area of Lake Cheimaditida will undergo a substantial decrease, initially by 20 % during the period 2020–2050 and later until 37 % during the period 2070–2100. In Lake Kerkini, the surface area will decrease, initially by 5 % during the period 2020–2050 and later until 14 % during the period 2070–2100. Climate change is anticipated to impact the hydroperiod of the two wetlands, and the sustainable water management is essential to prevent the wetland’s biodiversity loss.Lessons from the construction of a climate change adaptation plan: A Broads wetland case study
de R Kerry Turner, Maria Giovanna Palmieri, Tiziana Luisetti
In Integrated Environmental Assessment and Management, 12(4) (October 2016), 719-725
En ligne : onlinelibrary.wiley.com[...]
The dynamic nature of environmental change in coastal areas means that a flexible “learning by doing” management strategy has a number of advantages. This article lays out the principles of such a strategy and then assesses an actual planning and management process focused on climate change consequences for the Broads wetland on the East coast of England. The management strategy focused on the concept of ecosystem services (stocks and flows) provided by the coastal wetland and the threats and opportunities posed to the area by sea level rise and other climate change impacts. The analysis explores the process by which an adaptive management plan has been formulated and coproduced by a combination of centralized (vertical) and stakeholder social network (horizontal) arrangements. The process values where feasible the ecosystem services under threat and prioritizes response actions. Coastal management needs a careful balance between strategic requirements imposed at a national scale and local schemes that affect regional and/or local communities and social networks. These networks aided by electronic media have allowed groups to engage more rapidly and effectively with policy proposals. However, successful deliberation is conditioned by a range of context specific factors, including the type of social networks present and their relative competitive and/or complementary characteristics. The history of consultation and dialogue between official agencies and stakeholders also plays a part in contemporary deliberation processes and the success of their outcomes. Among the issues highlighted are the multiple dimensions of nature's value; the difficulty of quantifying some ecosystem service changes, especially for cultural services; and the problem of “stakeholder fatigue” complicating engagement arrangements. Integr Environ Assess Manag 2016;12:719–725. © 2016 SETACPossible effects of ingested lead gunshot on populations of ducks wintering in the UK
de Rhys E. Green, Deborah J. Pain
In Ibis, 158(4) (October 2016), 699-710
En ligne : onlinelibrary.wiley.com[...]
Although the use of lead ammunition for shooting wildfowl and/or over listed wetlands in the UK has been banned, c. 70% of ducks shot in England (the only UK country with compliance monitoring) are still shot with lead and the proportion of ducks found dead with signs of lead poisoning from ingested gunshot has not declined significantly since the ban. However, there is little quantitative evidence of the impacts of additional mortality from lead poisoning on duck populations. For the eight duck species that winter in freshwater habitats in the UK, we found that inter-specific variation in mean population growth rate during the period 1990/1991 to 2013/2014 was significantly negatively correlated with two independent measures of the prevalence of ingested lead gunshot in the UK and Europe. This relationship was found for a wide range of different periods over which population growth was estimated, and also for annual growth rates in the period 1966/1967 to 2013/2014, derived from smoothed population trajectories. These findings support the hypothesis that ingested lead gunshot might affect population trend. An alternative hypothesis, that migratory short-stopping driven by climate change affected trends in numbers of ducks wintering in the UK, was not supported by simple or partial correlation results. The possible impact of ingested lead gunshot on the Common Pochard Aythya ferina, a species listed as globally threatened, is of special concern.
de Matthieu Guillemain, Jocelyn Champagnon, Marie-Lucile Gourlay-Larour, Francois Cavallo, Anne-Laure Brochet, Jean Hars, Gregoire Massez, Thierry George, Pierre-Yves Perroi, Veronique Jestin, et al.
In Ibis, 158(4) (October 2016), 743-753
En ligne : onlinelibrary.wiley.com[...]
Concerns about the spread of avian influenza viruses (AIVs) have led to cloacal swab sampling of hundreds of thousands of birds worldwide as part of AIV surveillance schemes, but the effects of cloacal swabbing have not been adequately evaluated. We tested for differences between swabbed, swabbed and bled, and non-sampled wild ducks in terms of live re-encounter and dead recoveries for Common Pochard Aythya ferina and Tufted Duck Aythya fuligula, and also determined re-encounter and recovery rates for Mallard Anas platyrhynchos and Common Teal Anas crecca. No effects of sampling methods were detected, except in Teal. Re-encounter rates were lower in sampled Teal than in controls, with annual re-encounter probabilities being 25% and 35% lower in males and females, respectively. Teal possibly left or avoided sampling sites, or sought sites where they were less detectable after sampling. In general, no deleterious effects were found, suggesting that cloacal swabbing and blood sampling are suitable methods for conducting AIV surveillance in ducks.
de Tina Rambonilaza, Olivier Joalland, Elodie Brahic
In Journal of Environmental Management, 180 (September 2016), 272-279
En ligne : www.sciencedirect.com[...]
Within Europe, flood and coastal risk management is undergoing a major paradigm shift as it moves from an approach dominated by investment in flood defence and control infrastructure to another one in which non-structural measures are favoured. One research challenge consists in developing a better understanding of local population risk perception and its effects on prevention and preparedness actions in order to improve social acceptability of adaptive flood risk management. Landowners’ involvement in wetland management offer benefits beyond the line of their property. Accordingly, the purpose of this study is to achieve an empirical understanding of risk perception and self-protective behaviour among the landowners of the riparian marshes in the Gironde Estuary, in France. Application of the psychometric approach reveals that flood risk perception among landowners can be characterised by three synthetic variables that indicate on the degree of exposure, the sense of control and knowledge of the risk. Examining the relationships between these perceived risk dimensions and landowners’ participation in water structures management provides three profiles of self-protective behaviour distinguishing “vulnerable”, “autonomous”, and “passive” individuals. Finally, implications of our findings for the management of flood risk in estuarine environment which is often drained areas are discussed.
de Helen R. Sofaer, Susan K. Skagen, Joseph J. Barsugli, Benjamin S. Rashford, Gordon C. Reese, Jennifer A. Hoeting, Andrew W. Wood, Barry R. Noon
In Ecological Applications, 26(6) (September 2016), 1677-1692
En ligne : onlinelibrary.wiley.com[...]
Climate change poses major challenges for conservation and management because it alters the area, quality, and spatial distribution of habitat for natural populations. To assess species’ vulnerability to climate change and target ongoing conservation investments, researchers and managers often consider the effects of projected changes in climate and land use on future habitat availability and quality and the uncertainty associated with these projections. Here, we draw on tools from hydrology and climate science to project the impact of climate change on the density of wetlands in the Prairie Pothole Region of the USA, a critical area for breeding waterfowl and other wetland-dependent species. We evaluate the potential for a trade-off in the value of conservation investments under current and future climatic conditions and consider the joint effects of climate and land use. We use an integrated set of hydrological and climatological projections that provide physically based measures of water balance under historical and projected future climatic conditions. In addition, we use historical projections derived from ten general circulation models (GCMs) as a baseline from which to assess climate change impacts, rather than historical climate data. This method isolates the impact of greenhouse gas emissions and ensures that modeling errors are incorporated into the baseline rather than attributed to climate change. Our work shows that, on average, densities of wetlands (here defined as wetland basins holding water) are projected to decline across the U.S. Prairie Pothole Region, but that GCMs differ in both the magnitude and the direction of projected impacts. However, we found little evidence for a shift in the locations expected to provide the highest wetland densities under current vs. projected climatic conditions. This result was robust to the inclusion of projected changes in land use under climate change. We suggest that targeting conservation towards wetland complexes containing both small and relatively large wetland basins, which is an ongoing conservation strategy, may also act to hedge against uncertainty in the effects of climate change.
de Wen-Yong Guo, Carla Lambertini, Xiao Guo, Xiu-Zhen Li, Franziska Eller, Hans Brix
In Biological Invasions, 18(9) (2016/09/01), 2551-2561
En ligne : link.springer.com[...]
The environmental conditions in the new ranges of introduced plant species are often different from the conditions in their native ranges, and invasive plant species have been assumed to adapt to different environmental conditions by rapid ecological evolution in the invasive range after the introduction. Another interpretation of the change in plant traits after their introduction, however, is ecological fitting, which is based on the inherently high phenotypic plasticity of the species rather than on evolution. The Mediterranean haplotype M1 lineage of the wetland grass Phragmites australis was introduced to the coastal wetlands along the Gulf Coast of North America, where it is exposed to a different climate compared to its original range. The climate in the native range is arid or temperate with dry and hot summers, whereas the climate in the introduced range is warmer and has a higher and more uniform precipitation than that in the native range. This warmer and more humid environment is likely to pose different selection pressures to the plants in the introduced range and thus cause rapid evolutionary change and phenotypic differentiation in the introduced range. Here, we compared phenotypic traits of the M1 lineage from the native and introduced ranges in a common garden experiment to study the processes assisting the successful spread in the introduced range. Overall, the native and introduced groups were similar, but we detected a few phenotypic traits that diverged. Ecological fitting could be the fundamental mechanism by which the P. australis M1 lineage survives and spreads in the introduced Gulf Coast region. However, further research is needed to assess how the diverging traits observed in our study in Denmark (lower photosynthetic rates, lower chlorophylls concentration and higher leaf K concentration for the introduced than for the native genotypes) are expressed in the two ranges.
de L. L. Pardo-Domènech, A. Tifrea, M. N. Grigore, M. Boscaiu, O. Vicente
In Plant Biosystems, 150(5) (September 2016), 904-915
En ligne : dx.doi.org[...]
Proline (Pro) and glycine betaine (GB) contents were determined in two Mediterranean halophytes, Plantago crassifolia and Inula crithmoides, to assess their possible role in salt tolerance of both taxa. Plant material was collected in a littoral salt marsh under different environmental conditions, and from plants subjected to salt treatments in a growth chamber. Relative growth inhibition by NaCl indicated that I. crithmoides is more salt-tolerant than P. crassifolia, in agreement with the distribution of the two species in nature. Field and laboratory data confirmed GB as the major osmolyte responsible for osmotic adjustment in I. crithmoides, but with only a minor role – if any – as “osmoprotectant” in the salt tolerance of P. crassifolia. Under natural conditions, Pro contents were very low in both taxa, but increased to levels high enough to contribute significantly to osmotic balance when plants were artificially treated with 450–600 mM NaCl – higher salt concentrations than those they would normally encounter in their natural habitats. These data suggest that halophytes possess built-in mechanisms, such as accumulation of additional osmolytes, to rapidly adapt to increasing salinity levels in their natural ecosystems; for example, those expected to be caused by climate change in salt marshes in the Mediterranean region.Peregrine Falcon (Falco peregrinus) may affect local demographic trends of wetland bird prey species
de Risto Tornberg, Veli-Matti Korpimäki, Pentti Rauhala, Seppo Rytkönen
In Ornis Fennica, 93(3) (September 2016), 172-185
En ligne : www.ornisfennica.org[...]
de B. Duarte, J. C. Marques, I. Caçador
In Biological Invasions, 18(8) (2016/08/01), 2189-2205
En ligne : link.springer.com[...]
The recent IPCC WG2 5th Assessment Report (IPCC 2014), notes an increase in the frequency and duration of extreme climatic events, especially for the Mediterranean region. Together with climate change, the invasion of natural communities by non-indigenous species (NIS) constitutes a serious threat to biodiversity. One of these NIS is the American Spartina patens, now present in Western European marshes. The present study aims to understand the biochemical and photochemical responses of S. patens compared with S. maritima under extreme temperature events. Under normal and extreme heat conditions, S. patens had a higher photosynthetic efficiency (α), compared with cold wave events, where the native S. maritima was far more efficient. This reduced photosynthetic efficiency was mostly due to a decrease in the connectivity between photosystem II (PSII) antennae. This was accompanied by severe damage to the oxygen-evolving complex of PSII. On the other hand, S. patens oxygen evolving complexes (OECs) seem to be temperature insensitive. The light absorption capacity was maintained due to a higher net rate of reaction centre (RC) closure as a counteractive measure of the reduced number of RC, especially in S. maritima. The loss of connectivity between PSII antennae and damage in OECs under heat stress leads to a severe reduction in the maximum yield for photochemistry enhanced by the low probability of each absorbed quanta to produce electronic work. However, while S. maritima presents high energy losses under heat stress, S. patens developed efficient quenching mechanisms under thermal stress, through auroxanthin. In S. patens, cold wave-treated individuals also displayed a very active line of enzymatic defences for reactive oxygen species scavenging. In fact, only cold treated individuals of this species presented higher activities of anti-oxidant enzymes, revealing some degree of adaptation to this new environment. In contrast, in S. maritima the exposure to extreme heat periods led, in most cases, to a decrease in the enzymatic defences, leaving the cell prone to oxidative damage. In summary, S. patens appears to have a higher fitness for the incoming climatic scenarios, being more tolerant to heat stress, while S. maritima will have its photobiological fitness decreased. This will impose a shift in the salt marsh biodiversity, favouring the non-indigenous S. patens expansion.
de Stuart E. Newson, Nick J. Moran, Andy J. Musgrove, James W. Pearce-Higgins, Simon Gillings, Philip W. Atkinson, Ryan Miller, Mark J. Grantham, Stephen R. Baillie
In Ibis, 158(3) (July 2016), 481-495
En ligne : onlinelibrary.wiley.com[...]
The timing of migration is one of the key life-history parameters of migratory birds. It is expected to be under strong selection, to be sensitive to changing environmental conditions and to have implications for population dynamics. However, most phenological studies do not describe arrival and departure phenologies for a species in a way that is robust to potential biases, or that can be clearly related to breeding populations. This hampers our ability to understand more fully how climate change may affect species’ migratory strategies, their life histories and ultimately their population dynamics. Using generalized additive models (GAMs) and extensive large-scale data collected in the UK over a 40-year period, we present standardized measures of migration phenology for common migratory birds, and examine how the phenology of bird migration has changed in the UK since the 1960s. Arrival dates for 11 of 14 common migrants became significantly earlier, with six species advancing their arrival by more than 10 days. These comprised two species, Blackcap Sylvia atricapilla and Chiffchaff Phylloscopus collybita, which winter closest to Britain in southern Europe and the arid northern zone of Africa, Common Redstart Phoenicurus phoenicurus, which winters in the arid zone, and three hirundines (Sand Martin Riparia riparia, House Martin Delichon urbicum and Barn Swallow Hirundo rustica), which winter in different parts of Africa. Concurrently, departure dates became significantly later for four of the 14 species and included species that winter in southern Europe (Blackcap and Chiffchaff) and in humid zones of Africa (Garden Warbler Sylvia borin and Whinchat Saxicola rubetra). Common Swift Apus apus was the exception in departing significantly earlier. The net result of earlier arrival and later departure for most species was that length of stay has become significantly longer for nine of the 14 species. Species that have advanced their timing of arrival showed the most positive trends in abundance, in accordance with previous studies. Related in part to earlier arrival and the relationship above, we also show that species extending their stay in Great Britain have shown the most positive trends. Further applications of our modelling approach will provide opportunities for more robust tests of relationships between phenological change and population dynamics than have been possible previously.
de Ceyda Ozfidan-Konakci, Baris Uzilday, Rengin Ozgur, Evren Yildiztugay, A. Hediye Sekmen, Ismail Turkan
In Functional Plant Biology, 43(7) (2016/07/13), 575-589
En ligne : www.publish.csiro.au[...]
The worst case scenario of global climate change predicts both drought and salinity would be the first environmental factors restricting agriculture and natural ecosystems, causing decreased crop yields and plant growth that would directly affect human population in the next decades. Therefore, it is vital to understand the biology of plants that are already adapted to these extreme conditions. In this sense, extremophiles such as the halophytes offer valuable genetic information for understanding plant salinity tolerance and to improve the stress tolerance of crop plants. Turkey has ecological importance for its rich biodiversity with up to 3700 endemic plants. Salt Lake (Lake Tuz) in Central Anatolia, one of the largest hypersaline lakes in the world, is surrounded by salty marshes, with one of the most diverse floras in Turkey, where arid and semiarid areas have increased due to low rainfall and high evaporation during the summer season. Consequently, the Salt Lake region has a large number of halophytic, xerophytic and xero-halophytic plants. One good example is Eutrema parvulum (Schrenk) Al-Shehbaz & Warwick, which originates from the Salt Lake region, can tolerate up to 600 mM NaCl. In recent years, the full genome of E. parvulum was published and it has been accepted as a model halophyte due to its close relationship (sequence identity in range of 90%) with Arabidopsis thaliana (L. Heynh.). In this context, this review will focus on tolerance mechanisms involving hormone signalling, accumulation of compatible solutes, ion transporters, antioxidant defence systems, reactive oxygen species (ROS) signalling mechanism of some lesser-known extremophiles growing in the Salt Lake region. In addition, current progress on studies conducted with E. parvulum will be evaluated to shed a light on future prospects for improved crop tolerance.
de D. Kizil, I.B., Ismail, Anthony Olivier, K. Cicek
In Amphibians and Reptiles Conservations, 10(1) (June 2016), pp. 28-33
En ligne : amphibian-reptile-conservation.org[...]
A report of the occurrence of a dimorphic population of Smooth Newts in Lake Sazlı (Izmir, Western Anatolia, Turkey). During fieldwork on March 2015, 29 aquatic individuals (seven males, 22 females) were captured and of these individuals, five were paedomorphic (four males, one female). The metamorphic (83%) and paedomorphic (17%) ratio of the population is skewed to metamorphic. The mean snout-vent length (SVL) was 28.30 mm (range = 26.00−30.41), and total length (TL) was 57.66 mm (53.35−61.40) in paedomorphs. The average exterior gill length was 4.12 mm (2.64–4.71). The SVL was 39.99 mm (range = 33.44−39.93), and TL was 69.06 mm (66.19−79.17) in metamorphs. The possible reasons for the presence of facultative paedomorphosis in the population are discussed, with the dimorphic paedomorph hypothesis supportedAdaptation services of floodplains and wetlands under transformational climate change
de Matthew J. Colloff, Sandra Lavorel, Russell M. Wise, Michael Dunlop, Ian C. Overton, Kristen J. Williams
In Ecological Applications, 26(4) (June 2016), 1003-1017
En ligne : onlinelibrary.wiley.com[...]
Adaptation services are the ecosystem processes and services that benefit people by increasing their ability to adapt to change. Benefits may accrue from existing but newly used services where ecosystems persist or from novel services supplied following ecosystem transformation. Ecosystem properties that enable persistence or transformation are important adaptation services because they support future options. The adaptation services approach can be applied to decisions on trade-offs between currently valued services and benefits from maintaining future options. For example, ecosystem functions and services of floodplains depend on river flows. In those regions of the world where climate change projections are for hotter, drier conditions, floods will be less frequent and floodplains will either persist, though with modified structure and function, or transform to terrestrial (flood-independent) ecosystems. Many currently valued ecosystem services will reduce in supply or become unavailable, but new options are provided by adaptation services. We present a case study from the Murray–Darling Basin, Australia, for operationalizing the adaptation services concept for floodplains and wetlands. We found large changes in flow and flood regimes are likely under a scenario of +1.6°C by 2030, even with additional water restored to rivers under the proposed Murray–Darling Basin Plan. We predict major changes to floodplain ecosystems, including contraction of riparian forests and woodlands and expansion of terrestrial, drought-tolerant vegetation communities. Examples of adaptation services under this scenario include substitution of irrigated agriculture with dryland cropping and floodplain grazing; mitigation of damage from rarer, extreme floods; and increased tourism, recreational, and cultural values derived from fewer, smaller wetlands that can be maintained with environmental flows. Management for adaptation services will require decisions on where intervention can enable ecosystem persistence and where transformation is inevitable. New ways of managing water that include consideration of the increasing importance of adaptation services requires major changes to decision-making that better account for landscape heterogeneity and large-scale change rather than attempting to maintain ecosystems in fixed states.
de Danijel Ivajnšič, Nina Šajna, Mitja Kaligarič
In Landscape and Urban Planning, 150 (June 2016), 79-86
En ligne : www.sciencedirect.com[...]
Understanding the causes of patterns in plant distribution is especially important when we want to create new terrain for vegetation development for conservation purposes. In Škocjan Inlet Nature Reserve it was carefully planned for new mudflats and islets to be created along a microaltitudinal gradient, aiming to achieve the spontaneous development of at least three target habitat types (mudflats not covered by seawater at low tide, Mediterranean glasswort swards and Mediterranean saltmarsh scrubs, including the transitional forms between them) through the primary succession pathways. Thus, this study was actually projected as a field experiment, on the one hand, and as a practical conservation measure, to recover a degraded area, on another. Vegetation cover on the newly constructed mudflats changed by 92% over 6 years of succession. In general, un-vegetated mudflats decreased from 71% to 26%. In contrast to this, Mediterranean glasswort swards increased from 6.5% to 28.2%, whereas saltmarsh scrub had the longest positive trend, constantly gaining area from 2008 (0.6%) to 2012 (28.9%). Detailed mapping showed rather deterministic successional pathways, which make restoration plans for halophyte communities more predictable. The study shows that this “ecological experiment” might have concrete implications for the restoration or re-creation of halophyte plant communities along sedimentary seacoasts—in general, all priority habitats in the European Union. The approach of creating artificial terrain within coastal protected areas is especially important in the light of the climate change-driven rise in sea level, often in conjunction with the “coastal squeeze” phenomenon.
de Ahmed Megharbi, Fatiha Abdoun, Benamar Belgherbi
In La Terre et la Vie, 71(2) (juin 2016), 142-155
En ligne : documents.irevues.inist.fr[...]
Les marais de la Macta sont classés en site Ramsar et bénéficient actuellement à la fois de l’attention des autorités et des scientifiques. L’objectif de cet article est de réaliser une étude sur les rapports entre les facteurs environnementaux et les groupements végétaux le long d’un transect… /
The Macta marshes are classified as a Ramsar site and currently profit at the same time from the attention of both authorities and scientists. The aim of this article is to make a study on the relationship between the environmental factors and the plant groupings along a transect…
de I. Anza, D. Vidal, J. Feliu, E. Crespo, R. Mateo
In Applied and Environmental Microbiology, 82(10) (May 2016), 3092-3099
En ligne : aem.asm.org[...]
Avian botulism kills thousands of waterbirds every year, including endangered species, but information about the differences between species in vulnerability to botulism outbreaks and the capacity to act as carriers of Clostridium botulinum is still poorly known. Here, we estimated the vulnerability to botulism of 11 waterbird species from Mediterranean wetlands by comparing the number of affected birds with the census of individuals at risk. The capacity of different species to act as carriers was studied by detecting the presence of the C. botulinum type C/D botulinum neurotoxin (BoNT) gene in fecal samples and prey items of waterbirds in the wild and by the serial sampling of cloacal swabs of birds affected by botulism. We found differences among species in their vulnerabilities to botulism, probably related to feeding habits, season of arrival, turnover, and, possibly, phylogenetic resilience. The globally endangered white-headed duck (Oxyura leucocephala) showed mortality rates in the studied outbreaks of 7% and 17% of the maximum census, which highlights botulism as a risk factor for the conservation of the species. Invasive water snails, such as Physa acuta, may be important drivers in botulism epidemiology, because 30% of samples tested positive for the BoNT gene during outbreaks. Finally, our results show that birds may excrete the pathogen for up to 7 days, and some individuals can do it for longer periods. Rails and ducks excreted C. botulinum more often and for longer times than gulls, which could be related to their digestive physiology (i.e., cecum development).
IMPORTANCE Botulism is an important cause of mortality in waterbirds, including some endangered species. The global climate change may have consequences in the ecology of wetlands that favor the occurrence of botulism outbreaks. Here, we offer some information to understand the ecology of this disease that can be useful to cope with these global changes in the future. We have found that some species (i.e., coots and dabbling ducks) are more vulnerable to botulism and have a more relevant role in the onset and amplification of the outbreaks than other species (i.e., flamingos and grebes). Feeding habits can explain these differences in part; in addition to the well-known role of necrophagous fly maggots, we found here that water snails are frequent carriers of Clostridium botulinum. This is relevant, because these water snails can thrive in eutrophic and polluted wetlands, exacerbating other changes driven by climate change in wetlands.
de Julia Chacón-labella, Marcelino de la Cruz, David S. Pescador, Adrián Escudero
In Oecologia, 180(4) (April 2016), 975-987
En ligne : link.springer.com[...]
Evaluating community assembly through the use of functional traits is a promising tool for testing predictions arising from Niche and Coexistence theories. Although interactions among neighboring species and their inter-specific differences are known drivers of coexistence with a strong spatial signal, assessing the role of individual species on the functional structure of the community at different spatial scales remains a challenge. Here, we ask whether individual species exert a measurable effect on the spatial organization of different functional traits in local assemblages. We first propose and compute two functions that describe different aspects of functional trait organization around individual species at multiple scales: individual weighted mean area relationship and individual functional diversity area relationship. Secondly, we develop a conceptual model on the relationship and simultaneous variation of these two metrics, providing five alternative scenarios in response to the ability of some target species to modify its neighbor environment and the possible assembly mechanisms involved. Our results show that some species influence the spatial structure of specific functional traits, but their effects were always restricted to the finest spatial scales. In the basis of our conceptual model, the observed patterns point to two main mechanisms driving the functional structure of the community at the fine scale, “biotic” filtering meditated by individual species and resource partitioning driven by indirect facilitation rather than by competitive mechanisms.
de Héctor Rodríguez-pérez, Samuel Hilaire, François Mesléard
In Hydrobiologia, 767(1) (March 2016), 333-345
En ligne : link.springer.com[...]
Temporary ponds, acknowledged for their conservation value, are colonized by the invasive crayfish Procambarus clarkii. We have tested the consequences of this colonization for the ecosystem under two contrasted scenarios: one single individual arrival or three individuals arrival. We recreated the temporary pond ecosystem in 1 m2 tanks to investigate the impact of the two crayfish densities. We studied the macrophyte community composition and abundance, chlorophyll a and total suspended solids concentrations, and the diversity and functional composition of micro-crustacean and macro-invertebrate communities. We observed a reduction of macrophyte biomass in experimental crayfish mesocosms in comparison with control tanks, nearly 80 and 40% less in 3 and 1 crayfish/m2 tanks, respectively. The macrophyte community shifted, followed by a filamentous algae development, an increase of bare sediment and turbidity in crayfish tanks. The macro-invertebrate community suffered a richness loss of 28 and 22%, in 3 and 1 crayfish/m2 tanks, respectively. Functionally, macro-invertebrate diversity reduction most strongly affected the grazer, detritivore and predator trophic groups. Microcrustaceans seemed not to be affected by the introduction of the crayfish. The introduction of the crayfish greatly altered the ecosystem structure and subsequently the ecosystem functioning.
de Medwet, Paula Sainot, Abderrahim Smari
Paris, France : MedWet, Février 2016, 48p
En ligne : medwet.org[...]
de Michael J. Osland, Nicholas M. Enwright, Richard H. Day, Christopher A. Gabler, Camille L. Stagg, James B. Grace
In Global Change Biology, 22(1) (January 2016), 1-11
En ligne : onlinelibrary.wiley.com[...]
Due to their position at the land-sea interface, coastal wetlands are vulnerable to many aspects of climate change. However, climate change vulnerability assessments for coastal wetlands generally focus solely on sea-level rise without considering the effects of other facets of climate change. Across the globe and in all ecosystems, macroclimatic drivers (e.g., temperature and rainfall regimes) greatly influence ecosystem structure and function. Macroclimatic drivers have been the focus of climate change-related threat evaluations for terrestrial ecosystems, but largely ignored for coastal wetlands. In some coastal wetlands, changing macroclimatic conditions are expected to result in foundation plant species replacement, which would affect the supply of certain ecosystem goods and services and could affect ecosystem resilience. As examples, we highlight several ecological transition zones where small changes in macroclimatic conditions would result in comparatively large changes in coastal wetland ecosystem structure and function. Our intent in this communication is not to minimize the importance of sea-level rise. Rather, our overarching aim is to illustrate the need to also consider macroclimatic drivers within vulnerability assessments for coastal wetlands.
de M. Malavasi, R. Santoro, M. Cutini, A. T. R. Acosta, M. Laura Carranza
In Plant Biosystems, 150(1) (January 2016), 73-82
En ligne : dx.doi.org[...]
We analyze the spatial patterns of natural dune cover patches and their plant richness, comparing coastal sites with different levels of human pressure in central Italy. We created a detailed land cover map of dune sites. The spatial pattern of natural dune cover types was characterized by computing a set of patch-based metrics. To quantify patch plant richness, we used 16 m2 vegetation plots, randomly distributed on coastal dune cover types. For each patch, the richness of the entire pool of species and of three guilds (i.e., typical dune, ruderal, and alien species) was considered. We compared different levels of human pressure on coastal dunes focusing on pattern metrics and floristic information by using the nonparametric Kruskal–Wallis test. In sites with high human pressure, we have observed a general simplification in the natural dune spatial pattern and a decline of plant richness but with a specific response for each cover type. Alien and ruderal species presented low richness in all patches. In coastal dunes, the harsh ecological conditions and the strong sea–inland gradient shape the distribution of human activities and control the number of ruderal species. The approach effectively describes fragmentation and biodiversity in dune ecosystems.
de Stéphanie Fayolle, Céline Bertrand, Maxime Logez, Evelyne Franquet
In Annales de Limnologie, 52 (January 2016), 1-11
En ligne : www.limnology-journal.org[...]Tracking global change in ecosystem area:The Wetland Extent Trends index
de M.J.R. Dixon, J. Loh, N.C. Davidson, C. Beltrame, R. Freeman, M. Walpole
In Biological Conservation, 193 (January 2016), 27-35
En ligne : linkinghub.elsevier.com[...]
We present a method for estimating broad trends in ecosystem area based on incomplete and heterogeneous data, developing a proof-of-concept for the first indicator of change in area of natural wetland, the Wetland Extent Trends (WET) index. We use a variation of the Living Planet Index method, which is used for measuring global trends in wild vertebrate species abundance. The analysis is based on a database containing 1100 wetland extent time-series records and the method identifies and addresses ecological and biogeographic biases in the dataset. Globally, the natural WET index, excluding human-made wetlands, declined by about 30% on average between 1970 and 2008. Declines varied between regions from about 50% in Europe to about 17% in Oceania over the same period. The WET index fills an important gap in the ecosystem coverage of global biodiversity indicators and can track changes related to a number of current international policy objectives. The same method could be applied to other datasets to create indicators for other ecosystems with incomplete global data.Waterfowl foraging in winter-flooded ricefields: Any agronomic benefits for farmers?
de Anne Brogi, Claire Agnès Pernollet, Michel Gauthier-Clerc, Matthieu Guillemain
In AMBIO, 44(8) (DEC 2015), 793-802
En ligne : link.springer.com[...]
Winter-flooding of ricefields provides foraging habitat to waterfowl, which in return may bring agronomic benefits to farmers. Our study experimentally tested the effect of mallards (Anas platyrhynchos) on the standing stalks and weed seed bank in the Camargue (France), both of which present major challenges for farmers. Three duck densities were tested: (D1) 5 ducks ha(-1) (historical nocturnal density), (D2) 23 ducks ha(-1) (present nocturnal density), and (D3) 300 ducks ha(-1) (Asian rice-duck farming density). The ducks reduced the stalks significantly: -27 % (D1), -52 % (D2), and -91 % (D3). Conversely, they decreased the number of seeds by only 3 % (D3) and the seed mass by about 21 % (D1 and D3), which was not significant. Besides they had no effect on seed species richness. This study clearly demonstrates that the winter-flooding effect on straw decomposition can be enhanced by waterfowl foraging, hence showing an agronomic benefit from ducks to farmers. However, there was no clear effect in terms of seed bank reduction.
de Katrin Lowe, J. Guy Castley, Jean-Marc Hero
In Marine and Freshwater Research, 66(10) (October 2015), 886-899
En ligne : www.publish.csiro.au[...]
Amphibians that utilise temporary wetlands with unpredictable hydrology are living on the edge, maintaining viable populations under variable climatic conditions. Information on their breeding ecology will provide insight into their adaptive capacity and resilience to climate change. The environmental factors influencing breeding of a temporary wetland breeding frog (Litoria olongburensis) from eastern Australia were examined over two breeding seasons from August 2009 to March 2011. The influence of biotic and abiotic wetland characteristics on the abundance and seasonality of L. olongburensis aquatic larvae was quantified throughout the latitudinal range of the species. Substantial variation in yearly precipitation resulted in changes to the timing of breeding, and patterns of tadpole and predator abundance, which also varied along a hydroperiod gradient. Litoria olongburensis displayed adaptive strategies, including breeding when hydrological conditions were likely to last longest, and short time to hatching and metamorphosis. Concentrating breeding efforts early during wetland filling coincided with low predator densities. These pre-adaptations may reflect an adaptive capacity to predicted changes in frequency and reliability of precipitation as a result of climate change, and may apply to other temporary wetland species. Their conservation depends on preserving wetlands with a variety of hydroperiods within a landscape matrix.
de C. H. Greenberg, S. Goodrick, J. D. Austin, B. R. Parresol
In Wetlands, 35(5) (October-November 2015), 899-911
En ligne : link.springer.com[...]
Hydroregimes of ephemeral wetlands affect reproductive success of many amphibian species and are sensitive to altered weather patterns associated with climate change. We used 17 years of weekly temperature, precipitation, and water-depth measurements for eight small, ephemeral, groundwater-driven sinkhole wetlands in Florida sandhills to develop a hydroregime predictive model. To illustrate its utility for climate-change planning, we forecasted weekly wetland water-depths and hydroperiods (2012–2060) using our model and downscaled climate data from the CSIRO Mk3.5 Global Circulation Model under an A1B emissions scenario. We then examined how forecasted water depths and hydroperiods might alter reproductive success, and thereby populations, of five anuran species. Precipitation and water-depth from the prior week were significant predictors of water depth. Our model forecasted shallower depths and shortened hydroperiods for most wetlands when used with the CSIRO Mk3.5 A1B scenario. The forecasted hydroregimes would likely provide adequate reproductive opportunity for only one of the five species we examined. We demonstrate the utility of our model in examining how different climate-change scenarios might affect hydroregimes and, indirectly, biological diversity. Climate change uncertainty highlights the importance of retaining multiple, hydrologically diverse wetlands on landscapes to maximize the potential for successful reproduction by species having differing hydroregime requirements.The phenology of wetland submerged macrophytes related to environmental factors
de Sara Calero, William Colom, María Antonia Rodrigo
In Limnetica, 34(2) (2015), 425-438
En ligne : dialnet.unirioja.es[...]
Little information is available about the phenology (i.e., the timing of recurrent events in life cycles) of submerged aquatic plants although they play a key role in wetlands. To establish a long-term data series concerning the phenology of aquatic plants, we are monitoring an artificial shallow pond in a depression between sand dunes in Albufera de València Natural Park (Spain). The macrophyte diversity in the pond is moderate: two angiosperms (Potamogeton pectinatus and Utricularia australis) and four charophytes (Nitella hyalina, Chara aspera, Chara vulgaris and Chara hispida). We continuously monitored the underwater temperature, at two sites and depths, through the use of probes with data-loggers. Other water variables (such as sestonic chlorophyll a, salinity, pH and oxygen) were monitored monthly. Samples of macrophytes were collected frequently to record the emergence and maturation of flowers/seeds in angiosperms, and sexual organs/oospores in charophytes. The relationship of phenological features to water temperature was tracked by calculating growing degreedays (GDD). The timing of the emergence and maturation of the sexual organs (antheridia and oogonia) of C. hispida was
dependent on the water depth: both sexual organs had already ripened by 70 GDD in shallower water (where there was no clear interruption of sexual reproduction), whereas in deeper water antheridia achieved this at 270 GDD, oogonia at 325 GDD. Oospores required twice as much heat to ripen in deeper water as in shallower water. Although N. hyalina had a similar phenology, it required more time and accumulated heat to become fertile: more than 1000 GDD were needed to ripen the sexual organs and oospores. C. vulgaris’ sexual reproduction was detected in spring, whereas C. aspera specimens remained fertile during the whole year. Both studied angiosperms flowered in late spring and mid-summer. P. pectinatus produced fruits at 900 GDD, whereas neither fruits nor seeds were detected for U. australis. These initial data represent a first glance at the life cycle of the submerged macrophytes inhabiting this pond as well as at the basic environmental conditions that affect their phenology and which, in turn, are also influenced by climate change. It represents the first detailed study of the phenology of Mediterranean charophytes from wetlands, and it lays the foundation for our forthcoming research.
de Sidi Imad Cherkaoui, Saâd Hanane, Najib Magri, Mohamed-Aziz El Agbani, Mohamed Dakki
In Wetlands, 35(5) (2015), 913-922
En ligne : link.springer.com[...]
Since 2005, Morocco has designated 28 Important Bird Areas (IBA) and Ramsar wetlands for waterbirds, yet little is known about how waterbird communities are changing over time and space, within and between sites. We assessed the relationships between species numbers of overall breeding waterbirds, as well as those of Anatidae, Rallidae and Podicipedidae, and geographical, topographical and macrohabitat factors. Species richness of overall waterbirds and Anatidae were positively correlated with: (i) extent of emergent vegetation, (ii) number of plant species present, and (iii) altitude. Species richness of Rallidae was positively correlated with: (i) latitude, and (ii) different beds of emergent vegetation, while that of Podicipedidae was exclusively correlated with altitude. These results suggest that breeding waterfowl are significantly related to habitat characteristics, most importantly vegetation structure, and altitude. Our findings give support to the idea that large mountain wetlands protected areas provide valuable habitat to breeding waterbirds in this region, by providing larger buffer zones with fewer human activities, such as hunting, urbanization and tourism disturbance. This study provides a platform from which we can advance the scientific research on Moroccan IBA and Ramsar wetlands.Wetland Suitability and Connectivity for Trans-Saharan Migratory Waterbirds
de Ronny Merken, Evelien Deboelpaep, Joachim Teunen, Santiago Saura, Nico Koedam
In PLOS ONE, 10(8) (August 2015), e0135445
En ligne : journals.plos.org[...]
To complete their life cycle waterbirds rely on patchily distributed and often ephemeral wetlands along their migration route in a vast unsuitable matrix. However, further loss and degradation of remaining wetland habitats might lead to a configuration and size of stopovers that is no longer sufficient to ensure long-term survival of waterbird populations. By identifying optimal conservation targets to maintain overall habitat availability en route , we can accommodate an as yet absent functional connectivity component in larger management frameworks for migratory waterbirds, such as the Ramsar Convention and the EU Natura 2000 Network. Using a graph-based habitat availability metric (Equivalent Connected Area) we determine the functional connectivity of wetland networks for seven migratory waterbirds with divergent habitat requirements. Analyses are performed at two spatial extents both spanning the Mediterranean Sea and centered around Greece (Balkan-Cyrenaica and Greece-Cyrenaica). We create species-specific suitable habitat maps and account for human disturbance by species-specific disturbance buffers, based on expert estimates of Flight Initiation Distances. At both spatial extents we quantitatively determine the habitat networks’ overall functional connectivity and identify wetland sites that are crucial for maintaining a well-connected network. We show that the wetland networks for both spatial extents are relatively well connected and identify several wetland sites in Greece and Libya as important for maintaining connectivity. The application of disturbance buffers results in wetland site-specific reduction of suitable habitat area (0.90–7.36%) and an overall decrease of the network’s connectivity (0.65–6.82%). In addition, we show that the habitat networks of a limited set of species can be combined into a single network which accounts for their autoecological requirements. We conclude that targeted management in few but specific wetland complexes could benefit migratory waterbird populations. Deterioration of these vital wetland sites in Greece and Libya will have disproportionate consequences to the waterbird populations they support.
de Rossano Bolpagni, Andrea Piotti
In Phytocoenologia, 45(1-2) (2015-07-01), 69-84
In the European plains, up to eighty percent of riverine wetlands have been lost due to alteration of hydrological regime and catchment exploitation. This condition is expected to be further negatively exacerbated by climate change. To better understand the observed change in distribution patterns of hydro-hygrophilous vegetation in temperate and Mediterranean floodplains, a vegetation survey was conducted within the lower Oglio River reach in Northern Italy. This river is a mid-size, altered and nutrient-rich left tributary of the Po River. During the 2008 growing season, a total of 60 marginal aquatic habitats were investigated. Overall, 37 vegetation communities were detected, showing a clear predominance of hygrophilous herbaceous plant communities both in terms of representativeness (55.1%) and diversity (54.1%) with respect to woody (22.9% and 10.8%, respectively), and obligate aquatic vegetation (22.0% and 35.1%, respectively). Our main findings were (1) the widespread presence of highly opportunistic, non-native and invasive hygrophilous plant communities (largely dominated by Amorpha fruticosa, Phragmites australis s.l., Amaranthus spp., Bidens spp., and Cyperus spp.), and (2) the limited distribution of hydrophyte vegetation usually dominated by pleustophytes (e.g., Spirodela polyrhiza and Lemna spp.). The present study confirms the dominance of secondary plant communities characterized by the widespread presence of alien species in lowland over-exploited riverscapes, coupled with a low local representativeness of native willow (Salix alba, S. cinerea) communities and anchored macrophyte (batrachid, ceratophyllid, elodeid, myriophyllid) meadows. Total vegetation diversity is consistent with previous studies in similar ecological contexts; on the other hand, at the site scale, the diversity values were extremely low. This is especially true for the aquatic vegetation, and can be related to the high water turbidity and chlorophyll-a concentrations that prevent the establishment and colonization of submerged and rooted hydrophytes. Consequently, we stress the need for metabolic and biogeochemical indicators to assess the actual trophic status of lowland wetlands in order to clarify their potential to be restored.Competition Is a Strong Driving Factor in Wetlands, Peaking during Drying Out Periods
de A. Merlin, A. Bonis, C. Damgaard, François Mesléard
In PLOS ONE, 10(6) (June, 2015), e0130152
En ligne : journals.plos.org[...]
The aim of the study is to investigate the relative importance of plant-plant interactions with regard to flooding and drought effect on perennial plant performances in wetlands. Flooding is expected to be the major driver and, accordingly, the importance of drought is hardly if ever taken into account. Focusing on five widespread species, the growth, the survival and the competitive ability of plants were monitored on permanent plots spread along two elevation gradients. Flooding duration and drought intensity were found to vary substantially along the ~ 0.5 meter range elevation gradient. Flooding and drought alternate over the hydrological year and the pin-point surveys were thus conducted over the course of one year. The data were modeled taking into account survival, recruitment and competitive growth throughout flooding and drying out periods. Flooding and drought both directly impacted the plant performances and their competitive effect, with the effect of drought being much more general among species and of higher magnitude than flooding. The importance of competition was found to be high for all species, particularly during the drying out period. It varied more along the flooding gradient than along the drought gradient. The higher flooding tolerance shown by the studied species compared to drought may be related to species specific growth timing together with efficient response traits. These results offer new insights into the filters operating over the species pools. This suggests that the drying out period and drought conditions may be even more important for species’ relative success and the importance of competition than the flooding pattern. The general applicability of this result, obtained in mild Atlantic climate and fertile wetlands, remains to be studied.
de Claire Duchet, Evelyne Franquet, Laurent Lagadic, Christophe Lagneau
In Ecotoxicology and Environmental Safety, 115 (05/2015), 272-278
En ligne : linkinghub.elsevier.com[...]
To optimize their efficacy, some insecticides used for mosquito control are introduced into aquatic ecosystems where mosquito larvae develop (marshes, ponds, sanitation devices) and cannot escape from the treated water. However, this raises the question of possible effects of mosquito larvicides on nontarget aquatic species. Bacillus thuringiensis var. israelensis (Bti), which is well-known for its selectivity for Nematocera dipterans, is widely used for mosquito control all over the world. Spinosad, a mixture of spinosyns A and D known as fermentation products of a soil actinomycete (Saccharopolyspora spinosa), is a biological neurotoxic insecticide with a broader action spectrum. It is a candidate larvicide for mosquito control, but some studies showed that it may be toxic to beneficial or non-target species, including nonbiting midges. The present study was therefore undertaken to assess the impact of Bti and spinosad on natural populations of Polypedilum nubifer (Skuse) and Tanytarsus curticornis Kieffer (Diptera: Chironomidae) in field enclosures implemented in Mediterranean coastal wetlands. Unlike Bti, spinosad had a strong lethal effect on P. nubifer and seems to affect T. curticornis at presumed recommended rates for field application. Differences in the sensitivity of these two species to spinosad confirm that population dynamics need to be known for a proper assessment of the risk encountered by chironomids in wetlands where larvicide-based mosquito control occurs.Movement ecology of five Afrotropical waterfowl species from Malawi, Mali and Nigeria
de John Y. Takekawa, Shane R. Heath, Samuel A. Iverson, Nicolas Gaidet, Julien Cappelle, Tim Dodman, Ward Hagemeijer, William D. Eldridge, Scott A. Petrie, Gregory S. Yarris, et al.
In Ostrich, 86(1-2) (May 2015), 155-168
En ligne : dx.doi.org[...]
Habitat availability for Afrotropical waterbirds is highly dynamic with unpredictable rainfall patterns and ephemeral wetlands resulting in diverse movement strategies among different species. Movement strategies among waterfowl encompass resident, regional and intercontinental migrants, but little quantitative information exists on their specific movement patterns. We studied the movement ecology of five Afrotropical waterfowl species marked with satellite transmitters in Malawi, Mali and Nigeria. Resident species, including White-faced Whistling Ducks Dendrocygna viduata, Fulvous Whistling Ducks Dendrocygna bicolor and Spur-winged Geese Plectropterus gambensis, remained sedentary during the rainy season and only flew limited distances during other months. In contrast, Knob-billed Ducks Sarkidiornis melanotos made short regional movements >50 km in all months and showed little site fidelity to previously used habitats in subsequent years. Garganey Anas quequedula followed an intercontinental strategy and made long-distance jumps across the Sahara and Mediterranean to their Eurasian breeding grounds. Most species flew farthest during the dry season, as mean daily movements varied from 1.5 to 14.2 km and was greatest in the winter months (January–March). Total distance moved varied from 9.5 km for White-faced Whistling Ducks (October–December) to 45.6 km for Knob-billed Ducks (April–June). Nomadic behaviour by Knob-billed Ducks was evidenced by long exploratory flights, but small mean daily movements suggested that they were relying on previous experience. Improving our understanding of these movement strategies increases our ability to assess connectivity of wetland resources that support waterfowl throughout their annual cycle and focuses conservation efforts on their most important habitats.
de Michela Faccioli, Antoni Riera Font, Catalina M. Torres Figuerola
In Environmental Management, 55(3) (March 2015), 550-563
En ligne : link.springer.com[...]
Climate change will further exacerbate wetland deterioration, especially in the Mediterranean region. On the one side, it will accelerate the decline in the populations and species of plants and animals, this resulting in an impoverishment of biological abundance. On the other one, it will also promote biotic homogenization, resulting in a loss of species’ diversity. In this context, different climate change adaptation policies can be designed: those oriented to recovering species’ abundance and those aimed at restoring species’ diversity. Based on the awareness that knowledge about visitors’ preferences is crucial to better inform policy makers and secure wetlands’ public use and conservation, this paper assesses the recreational benefits of different adaptation options through a choice experiment study carried out in S’Albufera wetland (Mallorca). Results show that visitors display positive preferences for an increase in both species’ abundance and diversity, although they assign a higher value to the latter, thus suggesting a higher social acceptability of policies pursuing wetlands’ differentiation. This finding acquires special relevance not only for adaptation management in wetlands but also for tourism planning, as most visitors to S’Albufera are tourists. Thus, given the growing competition to attract visitors and the increasing demand for high environmental quality and unique experiences, promoting wetlands’ differentiation could be a good strategy to gain competitive advantage over other wetland areas and tourism destinations.
de S. Guareschi, P. Abellán, A. Laini, A. J. Green, J. A. Sánchez-Zapata, J. Velasco, A. Millán
In Ecological Indicators, 49 (February 2015), 204-215
En ligne : www.sciencedirect.com[...]
Wetlands are among the most threatened habitats and the species they support among the most endangered taxa. Measuring and monitoring wetland biodiversity is vital for conservation, restoration and management, and often relies on the use of surrogate taxa. Waterbirds are commonly used as flagships of biodiversity and are the subject of major conservation initiatives. Therefore, it is important to assess the extent to which waterbirds indicate the general biodiversity of wetlands and serve as surrogates.
We explore the relationships between community composition and species richness of waterbirds and aquatic macroinvertebrates in 36 Ramsar wetlands in southern Spain to assess if waterbirds are good surrogates for other taxonomic groups. Specifically, we aimed to (i) test the congruence of patterns of species composition and richness among waterbirds and aquatic macroinvertebrates; and (ii) investigate which environmental variables are associated with the biodiversity patterns of waterbirds and macroinvertebrates, with the purpose of identifying key factors explaining potential discordance in these patterns.
We found a limited concordance between assemblage patterns of both taxonomic groups that may be related to their contrasting responses to environmental gradients. Assemblages of waterbirds appear to be more affected by climate variables and water surface area, whereas conductivity was the most important factor influencing macroinvertebrate communities. Furthermore, we found a negligible or inverse relationship in their patterns of richness, with wetlands with higher waterbird species richness showing significantly lower richness of Hemiptera and macroinvertebrate families, and no significant relationship with Coleoptera. In addition, GLM models showed that, in general, different environmental variables are related with the richness patterns of the different taxonomic groups.
Given the importance of the Ramsar convention for the conservation of an international network of wetlands, our findings underline the limited potential of waterbirds as aquatic biodiversity indicators in Mediterranean wetlands, and the need for caution when using waterbirds as flagships. An integrative analysis of different biological communities, using datasets from different taxonomic groups, is a necessary precursor for successful conservation policies and monitoring. Our results illustrate the need to create a diversified and complete network of protected sites able to conserve multiple components of wetland biodiversity.
de Roberta Aretano, Teodoro Semeraro, Irene Petrosillo, Antonella De Marco, Maria Rita Pasimeni, Giovanni Zurlini
In Ecological Modelling, 295 (janvier 10, 2015), 163-175
En ligne : www.sciencedirect.com[...]
The challenge for conservation managers is to ensure the long-term sustainability of an area by preserving its ecological and cultural values against predictable and unpredictable natural and human pressures and, at the same time, ensuring the fruition of the environmental resources. This research proposes an integrated use of GIS–based Decision Support System (DSS) with a conceptual linear model of vulnerability to foster conservation strategies in protected areas, by identifying: (1) the most vulnerable areas, requiring specific protection measures to enhance the natural features, as well as the prevention of natural and human risks; (2) the most effective management interventions to reduce system vulnerability to fire. The development of such a tool has been tested on the natural protected area of Torre Guaceto, through the selection of suitable indicators that enable discrimination among different levels of sensitivity and pressures, in order to provide evidence of its potential utility for the management of protected areas and the mitigation of their vulnerabilities. The results highlight that the most vulnerable areas are represented by contiguous patches of wetlands, the load of fuel at wetlands-agricultural lands interface areas, and the small patches of century-old forests, Mediterranean maquis and coastal dunes. On the basis of the results it is desirable that future researches on vulnerability should not only consider the “of what to what”, but also consider “for who, where and when” with a focus on the spatial and temporal scale dimensions of vulnerability.
de P. Ezanno, M. Aubry-Kientz, S. Arnoux, P. Cailly, G. L’Ambert, C. Toty, T. Balenghien, A. Tran
In Preventive veterinary medicine, 120 (January 1, 2015), 39-50
En ligne : www.sciencedirect.com[...]
An accurate understanding and prediction of mosquito population dynamics are needed to identify areas where there is a high risk of mosquito-borne disease spread and persistence. Simulation tools are relevant for supporting decision-makers in the surveillance of vector populations, as models of vector population dynamics provide predictions of the greatest risk periods for vector abundance, which can be particularly helpful in areas with a highly variable environment. We present a generic weather-driven model of mosquito population dynamics, which was applied to one species of each of the genera Anopheles, Culex, and Aedes, located in the same area and thus affected by similar weather conditions. The predicted population dynamics of Anopheles hyrcanus, Culex pipiens, and Aedes caspius were not similar. An. hyrcanus was abundant in late summer. Cx. pipiens was less abundant but throughout the summer. The abundance of both species showed a single large peak with few variations between years. The population dynamics of Ae. caspius showed large intra- and inter-annual variations due to pulsed egg hatching. Predictions of the model were compared to longitudinal data on host-seeking adult females. Data were previously obtained using CDC-light traps baited with carbon dioxide dry ice in 2005 at two sites (Marais du Viguerat and Tour Carbonnière) in a favourable temperate wetland of southern France (Camargue). The observed and predicted periods of maximal abundance for An. hyrcanus and Cx. pipiens tallied very well. Pearson's coefficients for these two species were over 75% for both species. The model also reproduced the major trends in the intra-annual fluctuations of Ae. caspius population dynamics, with peaks occurring in early summer and following the autumn rainfall events. Few individuals of this species were trapped so the comparison of predicted and observed dynamics was not relevant. A global sensitivity analysis of the species-specific models enabled us to identify the parameters most influencing the maximal abundance of mosquitoes. These key parameters were almost similar between species, but not with the same contributions. The emergence of adult mosquitoes was identified as a key process in the population dynamics of all of the three species considered here. Parameters associated with adult emergence therefore need to be precisely known to achieve accurate predictions. Our model is a flexible and efficient tool that predicts mosquito abundance based on local environmental factors. It is useful to and already used by a mosquito surveillance manager in France.
de Helen Moor, Kristoffer Hylander, Jon Norberg
In AMBIO, 44(1) (2015/01/01), 113-126
En ligne : link.springer.com[...]
Wetlands provide multiple ecosystem services, the sustainable use of which requires knowledge of the underlying ecological mechanisms. Functional traits, particularly the community-weighted mean trait (CWMT), provide a strong link between species communities and ecosystem functioning. We here combine species distribution modeling and plant functional traits to estimate the direction of change of ecosystem processes under climate change. We model changes in CWMT values for traits relevant to three key services, focusing on the regional species pool in the Norrström area (central Sweden) and three main wetland types. Our method predicts proportional shifts toward faster growing, more productive and taller species, which tend to increase CWMT values of specific leaf area and canopy height, whereas changes in root depth vary. The predicted changes in CWMT values suggest a potential increase in flood attenuation services, a potential increase in short (but not long)-term nutrient retention, and ambiguous outcomes for carbon sequestration.
de Matthieu Guillemain, Claire Agnès Pernollet, Gregoire Massez, F. Cavallo, G. Simon, Jocelyn Champagnon
2015
A large body of research has accumulated on the impact of climate change on wildlife movements and distributions, especially for migratory birds. We used large ringing datasets for the Common Teal (Anas crecca) from the Camargue, southern France, to compare historic (from 1956-1975) spatiotemporal patterns of teal recovery with those seen in modern (2002-2012) years and assess whether the migration phenology of these ringed birds and their use of the Camargue as winter quarters has changed. Because teal are short-distance migrants (i.e., they breed in northern Europe and winter north of the Sahara), they would be predicted to delay their autumn migration in response to climate change. Conversely, ring recoveries showed that teal are now arriving much earlier: a stable 80 % of the recoveries were made locally in the Camargue each week between mid-November and late January in the modern dataset, whereas this percentage was only 53 % on average in the older data, and the proportion of recoveries made locally in the Camargue gradually increased through the autumn and winter until late January. This suggests that Camargue habitats have changed markedly and become more attractive to teal compared to other potential wintering areas, consistent with known changes in local habitat management practices and improvements in the body condition of the birds. Despite the fact that global climate change will likely be one of the main drivers of wildlife distribution over the long term and at large spatial scales, local habitat management should not be overlooked, as it can increase habitat attractivity to migratory birds.Native European eel as a potential biological control for invasive crayfish (2015)
de C. Musseau, C. Boulenger, Alain Jean Crivelli, I. Lebel, M. Pascal, S. Boulêtreau, F. Santoul
2015
de Jean-Yves Mondain-Monval, P. Defos Du Rau, Matthieu Guillemain, Anthony Olivier
2015Development of an Indicator to Monitor Mediterranean Wetlands (2015)
de A. Sanchez, D. Abdul Malak, Anis Guelmami, Christian Perennou
2015
de Gaëtan Lefebvre, Christophe Germain, Brigitte Poulin
2015
Mediterranean wetlands are increasingly managed to maintain their functions and services following modification in water allocation, embankment and climate change, calling for proactive and adaptive water management. In a first step, we used long-term monitoring of water levels in 37 adjacent embanked marshes in the Camargue as a repeated non-controlled experiment to build a hydrological model. Without information on water input/output by marsh users, we could nevertheless estimate evapotranspiration under flooding and dry conditions, and soil water coefficient. The model provided a high predictive accuracy (adjusted R-2 = 0.73-0.83) of monthly water levels when applied to an independent sample of 12 marshes. In a second step we developed an interactive decision-aid tool that allows users to visualize the impact of their management strategy (desired water level at a specific month) on subsequent water levels, and their consequence on different components of the ecosystem over a 10-yr period. (C) 2015 Elsevier Ltd. All rights reserved.
de Philippe Lambret, A. Besnard, N. Matushkina
2015
de Philippe Lambret, A. Besnard, N. Matushkina
2015
Biotic and abiotic features impact the breeding success of animals and thereby induce selection pressures for habitat selection. Little is known about the plant selection by predatory insects which lay their eggs within plants. In previous work, the authors have highlighted that during oviposition males of Lestes macrostigma—an endangered dragonfly species—prefer to land on Bolboschoenus maritimus and dead shoots of Juncus maritimus but disfavour living shoots in that species, and that females seem to prefer dead material during substrate examination. In this study the authors assessed behavioural preference in females during substrate examination, substrates suitability for oviposition, the effort females had to make to lay their eggs and their resulting oviposition rate. We show L. macrostigma has a preference for B. maritimus and, albeit to a lesser extent, for dead substrates.Pododermatitis in Captive and Free-Ranging Greater Flamingos (Phoenicopterus roseus) (2015)
de F. Wyss, V. Schumacher, C. Wenker, S. Hoby, S. Gobeli, Antoine Arnaud, M. Engels, M. Friess, C. E. Lange, M. H. Stoffel, et al.
2015
