Diversity and community structure of beetles in Yunwu Mountain grassland, NingXia

In order to investigate the community structure and species diversity of beetles in five sampling areas including core grassland region, core forest region, caragana land, buffer grassland region, experimental grassland region in Yunwu Mountain National Nature Reserve of Ningxia, the survey combined pitfall trap and sweep net was conducted from June to September in 2013. A total of 8 841 beetles, belonging to 95 species from 23 families, were collected. Carabidae, Cetoniidae, Tenebrionidae, Scarabaeidae and Silphidae were dominant groups in Yunwu Mountain National Nature Reserve because Carabidae had 4 762 individuals which was maximum, accounted for 53.86%, and Cetoniidae was second maximum, accounted for 19.32%, and Tenebrionidae, Scarabaeidae and Silphidae had more individuals than other families. Both Shannon diversity index and species richness index of beetles were the highest in the core forest region which was 2.25 and 7.55, respectively. Both dominance index and species richness index were the lowest in core grassland region. Both Shannon diversity index and evenness index were the lowest in the caragana land. There were no significant difference（P＞0.05） for evenness index between these five sampling sites. The similarity analysis showed that the similarity coefficient buffer area and experimental area was 0.514 7 which was moderately similar, the similarity coefficient between the others ranged from 0.25 to 0.5 which was moderately dissimilar.