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Résumé :
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The temporary ponds have been less studied in Northern Africa than in Mediterranean Europe. Moreover, no study is devoted to the ecology of these ponds in Numidia (North-Eastern Algeria). Thus to fill this gap, we have surveyed 26 temporary ponds and we have examinated the fluctuations of plant assemblages and hydrology. These samples were performed monthly (nine months) during the hydroperiod and along three annual cycles (19982001). The studied ponds are distributed along two transects of 90 km. We obtain a table of 539 releves and 136 plant taxa. This table was submitted to an ACP and then to a Discrimin : Between analysis. This analysis allows to distinguish temporal and spatial effects : the first describes the succession of taxa, and the second the typology of ponds. Our results show that the temporal effect conveyied two periods (summer-autumn and winter-spring) with respectively Panicum repens and Ranunculus baudotii. The spatial effect permits to divide the twenty-six temporary ponds into three groups: group 1, Characeae and Juncus acutus; group 2, Callitriche obtusangula and Isoetes velata subsp. typica; group 3, C. obtusangula and Alisma plantago-aquatica.An appendix includes a detailed description of these 26 temporary ponds, with some data related to plant richness and a focus about the most outstanding biogeographic elements present within the "afrotropical relict pocket".
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