Community Diversity of Litter-layer Beetles in the Baijitan National Nature Reserve of Ningxi

The community structure and species diversity of litter-layer beetles in five habitats in Baijitan National Nature Reserve of Ningxia were surveyed from July to September in 2006. A total of 1896 beetles were collected by pitfall traps and other methods during field research. The result showed that all specimens belong to seventeen families. The individual of Tenebrionidae was the maximum, accounts for 25.58%; Chrysomelidae takes the second place, accounts for 20.99%; the individuals of Eumolpidae, Meloidae and Coccinellidae were also rich more than other families. These five families were considered as dominant groups. Among the five habitats, the individuals and species abundance of litter-layer beetles were the highest in the Baijitan plot, but the lowest in the Maanshan plot. The indices of species richness, diversity and evenness were the highest in the Changliushui plot, while the lowest in the Maanshan plot. Cluster analysis showed that the community structures and habitats were similar among the Daquan plot, Ciyaobao plot, Changliushui plot as well as Baijitan plot. It is particularly more similar between Changliushui plot and Ciyaobao plot. The community composition and diversity of litter-layer beetles were closely related to the spatial heterogeneity which was restored by the practice of desertification control.