The Study On The Structures And Diversities Of Bird Communtiy In Different Landscapes At Forest-steppe Ecotone

The bird communities were studied in three different landscapes of Sehanba national forest park from May to Septmber 2005:the composition of the bird communities and fauna of analysis;the structural of bird communities change in different landscapes;the vertical structure of bird communities change in different landscapes;the niche of bird communities change in different landscapes;the relations between bird communities and landscape heterogeneity;the relation between bird communities and vegetation structures.The major conclusions from this research are following;The bird resource was investigated in Sehanba of Hebei.There were 44 species of birds belonging tol7families and8 orders.There were 15 species and 8 families belonging to non-Passeriforme,accounting for 34.1%of total numbers of species,29sp-cies and 9 families belonging to Passeriforme,accounting for 65.9% of total numbers of species.Among non-Passeriforme,Falcaniforme were 5 species and 2 familier,acco-unting for 11.4% of the total numbers of species;Galliforme were 4 speciesk,accounti-ng for 9.1% of the total numbers.It embodied the composition characteristics of bird communities in forest-stepped ecotone from forest zone to steppe zone gradually trastion.To statistics with resident,there were 22 species(50%) of summer resident,17 species (38.6%) of resident,4 species(9.1%) of travelers and 1 species of stragglers.A-mong them,6 species were national Second-grade protected wildlife,including Falco-tinnunculus, Falco vespertinus, Falco subbuteo ,Falco lamurensis, Accipiter nisus and Athene noctua.There were distinct characterisitics of the Northe China avifauna and the Pacific monsoon area avifauna,and 3 6species of palearotic birds(73.3%),9 epidemic(20%),3 oriental(6.7%).Under three different landscapes,the sequence of species richness was:forest landscapes>meadow-steppe landscape > forest-meadow landscape;the diversity indices bird communities was:forest landscape> meadow-steppe landscape> forest-meadow landscape.Space heterogenerity higher, the more complex structure of bird communit-ies.Each bird had its own suitable breeding habitats, so that the different habitats of the birds had its own unique communities.Under three different landscapes, the similarity of bird communities between vertical space was: meadow-steppe landscape > forest-meadow landscape > forestlandscape, the higher the coefficient of similarities, the smaller different between vertical space. The reason for this different was caused by different lanscapes of the different levels of vegetation.To study respectively niche breadth and niche overlap of four similar birds under three different landscapes,thus analysis the niche change and bird communities for the use of resource. The niche change of four birds under three different landscapes was: forest landscape > meadow-steppe landscape > forest-meadow landscape.This trend reflectd the change of four birds for resource with habitat changed.The degree of landscape heterogeneity under three different landscapes was: forest landscape > meadow-steppe landscape > forest-meadow landscape. The higher degree of landscape heterogeneity, the higher indices diversity of bird communities. The change of three different types of landscape heterogeneity and the change of diversity of bird communities were consistent.Through researched relation between birds communities and vegetation structure under three different landscapes, and found out the characteristics affecting composition of bird communities. In the forest landscape, the major factors impacted bird communities were canopy over and canopy closure;in the forest-meadow landscape, the major factors impacted bird communities were canopy over and average height;in the meadow-steppe landscape, the major factors impacted bird communities were stand age and canopy closure.