Landscape structure and breeding bird distribution in a sub-Mediterranean agro-ecosystem

摘要: Richness, abundance and distribution of birds were investigated in the Aulella watershed,a mountainous area 300 km2, located extreme northwestern corner Tuscany, Italy spring summer, 1995. The study encompasses five vegetation types (from Mediterranean maqui to upland beech forest) three main land use categories (woodlands, mixed cultivated + urban areas, montane prairies). recent history abandonment has produced a rapid expansion shrubland woodland, reducing areas small patches interspersed woodland matrix. recorded at 414 points, randomly selected along secondary roads, using Global Positioning System (GPS), compared with topography, type Geographic Information Systems (GIS) grid cell resolution 200 × m. Bird richness (55 species all) are correlated: (a) negatively increasing altitude distance from areas; (b) positively woodlands mountain prairies. Slope orientation appears have negligible effect on bird assemblages. significantly correlated type. Cultivated support highest that increase patch size areas. Local extinction and/or reduction within-species expected continue if process continues.