{A model for integrating the habitat requirements of threatened animal species and the physionomical structure of vegetation of the territory applied to the building of the Ecological Network in Marches region (Italy)}

The extreme difficulty in relating data on the presence, diffusion and dispersion of the populations of middle-and large-sized vertebrates and the heterogeneity of the ecological structure (habitat) of the territory is evident in the scientific literature. Studies on vegetation have produced very plausible and effective models, and maps of the different vegetation typologies distribution, according to middle-long term variables, which can be well represented by means of cartography. On the contrary, the ability of "mobility and contemporary use of several habitat", which is typical of birds and mammals, does not allow to characterize easily and exactly the spatial distribution of the populations of the different species. Furthermore, the variability of the models of animal diffusion and dispersion (phylopatry and migration) does not allow producing univocal and reliable cartographic representations, except for populations homogeneously distributed in stable and wide natural habitats. However, the millenary anthropic action has generally led in Europe and also in Italy to an increasing fragmentation of the territory and the habitats. This fact calls into question also the hypotheses on the potential faunistic distribution, which are regrettably widely used with lack of thought. We have wondered how to characterize single animal species, birds in this case, in relation to the use that they make of the habitats in their phenological moments (breeding, feeding, resting and migration), which are basic for the survival and conservation of the population. The goal of this work has been the integration of the wide and reliable information available in the scientific literature on the various species, concerning their reproductive and alimentary habitat and microhabitat selection, and the connection of these data, by means a GIS system, to the real distribution of vegetation (represented by phytosociological method), to the real land use and the structural and physionomical features of the whole vegetation typologies of the territory. Several surveys carried out in 2004-2005 on the presence and distribution of the species in SIC and ZPS have allowed to realize a cartographic representation of the real distribution of the species of community interest, and relate it to the change and the variability of the habitats. This methodology also allows also to realize reliable maps of the potential distribution of bird species, because they are connected to the real use of the present habitats and to the specific ecological and ethological features (dispersion models included) of the various species of the existing community. {\textcopyright} Societ{\`{a}} Italiana di Scienza della Vegetazione.