Biodiversity gradients in the Alps: the overriding importance of elevation

摘要: Land abandonment is causing woodland expansion and loss of open habitats in the Alps, coupled with a shift forestry practices from coppice management to high forest. Despite such rapid large-scale changes, there has been very little investigation environmental predictors biodiversity Alpine landscape. We assessed richness amphibians, reptiles breeding birds (n = 189 species), used as surrogate biodiversity, 58 quadrats 100 km2, located within well surveyed area province Trento (central-eastern Italian Alps). The surrogates were then related series variables by means stepwise multiple regression. Depending on analysed, species declined linearly or quadratically elevation, increased habitat heterogeneity availability grassland arid-rocky habitats. same results obtained when incorporating measure threat into estimates. Different positively inter-correlated, probably because common response factor, namely which was only variable enter all models. Such elevational gradient produced clear peak low-elevation areas, generating potential conflict between efficient conservation economic interests linked human development, scenario applies many mountain regions worldwide. current network protected areas quite satisfactory terms covered but biased towards high-elevation scenic beauty relatively low animal value. Low-elevation reserves small isolated. Proposed targets include establishment corridors increasing connectivity promotion incentives for extensive grassland, an agro-ecosystem historical biological