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Résumé :
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Following an introduction to urban geography and ecology, in which villages and towns are characterized by their basic features, a short review is given to human settlement history in Central Europe. In the area that today is Germany, the first villages and towns were only built about 2000 years ago. According to the land-use statistics of the Federal Republic of Germany, 11.8% of the total area is covered by settlements and traffic structures, while 5.9% of the total area have an urban character. These areas provide habitats for large numbers and quite a variety of birds, but represent distribution gaps for numerous other species. The specific environmental conditions of settlement ecosystems are characterised and essential habitat types are described. The urbanisation process in birds is an adaptation to specific environmental conditions of settlement areas. By modifying and extending the scheme of SEAMANN (1970), I distinguish species with preference for rural villages, for larger towns and cities, for settlements in general, species increasingly colonising settlements and neutral species. Bird communities of settlements are described in a table listing indicator species ('Leitarten') and other characteristic species. Whilst few species show real synanthropy, the process of urbanisation involves many species; some examples documented in literature are reviewed with emphasis on possible causes. Primary habitats of these species are, on the hand, rocks for which they find a substitute in buildings and, on the other hand, bushy and woodland areas of a structure similar to urban parks and gardens. Nature conservation must include concepts of conserving birds in villages and towns, including the various processes that (re)create the habitats they require. Birds and bird communities can serve as indicators of the quality of the urban environment. Ornithology and nature conservation should integrate their knowledge into the discussion about sustainable village and urban development that has been instigated by the Agenda 21.
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