西双版纳热带雨林环境变化对蝗虫区系成分和物种多样性的影响

Influences of habitat changes in the tropical rainforest on the fauna and species diversity of Acridoidea in Xishuangbanna

西双版纳地区已经记录蝗总科６科４８属７９种。其中８６．１％的种类是东洋区成分，包括２２个特有种，其余１３．９％为广布种。随着雨林的垦伐和生境的变化，物种成分正在发生明显的变化。不仅物种数量逐渐下降，而且东洋区物种成分减少，广布种成分增加，特有的物种也因生境的单调化而减少甚至消失。多样性指数和均匀度指数沿着雨林—灌丛—农田—橡胶林生境梯度的变化呈显著下降的趋势。龙山部分地保持了雨林生境的特征，但是对保持蝗虫物种多样性方面的作用很有限。

Hitherto, six families, 48 genera and 79 species of Acridoidea have been recorded in the tropical region of Xishuangbanna. Of them, 68 species accounting for 86.1% of the total species are oriental, including 22 endemic species. The other 11 species are widely distributed. As the destruction of the tropical forest, cultivation of crops and other plants of economical importance, habitats with tropical rainforest characters have been changing in this area. The fauna and the species diversity of Acridoidea are influenced. The number of species is gradually reducing. The ratio of the oriental species decreases and that of widely distributed species increases. Some endemic species decline or even extinct because of the environmental change. The diversity analysis showed that species diversity index and evenness index of Acridoidea will significantly decrease from 1.240 to 0.761 and from o.887 to 0.585 respectively along the rainforest—bush—farmland—rubber trees habitats. Holy hills can maintain some characters of rainforest habitats, but its role in the conservation of grasshopper species is limited.