The case study on soil fauna diversity in different ecological system in Shilin national park, Yunnan, China
C. Xiang, L. Song , P. Zhang , G. Pan - (32/2,2003)
A preliminary study of the distribution and diversity of soil fauna in a sequence of ecosystem degradation in the Shilin National Park, Yunnan, China has been made. The degraded ecologic system includes 5 types of vegetation cover: (1) natural bush, (2) human planted cypress forest, (3)natural grass, (4)secondary grass and (5) bared red earth. A quadrate of 1m_1m in each eco-tessera was sampled for soil fauna collection. The animals were obtained either by picking up or by heat-removing. The soil fauna were dominated by Acarina, Collembola, Nematode, Coleoptera,and Opistopora in these soils. However, Erchytraeidae, Araneida, Lepidoptera and Diptera were also common groups. The diversity index H turned to be less than 1.5, drastically decreasing with the vegetation degradation trend. In the karst soils, Parholaspidae was one of the most populous among the mites. The biomass of Trhypochthoniidae and Ologamasidae was very concentrated in the natural bush ecosystem, showing high sensitivity of mites to vegetation degradation. The biomass ratio of Acarina to Collembola in the studied soils ranged from 0.70 to 1.50, which was in great discrepancy to the results reported of the natural soils at similar latitude. The small soil fauna biomass and less diversity indicated that the studied soil was in a state of deterioration of soil fauna habitats and, in turn, the soil ecosystem health. The results also evidenced that the soil fauna in the karst soil was definitely vulnerable as regarded to the sustainable development of the Shilin Park.