| The current situation, problems, development and orientation of the insect species diversity researches in China are analyzed and discussed briefly. The diversity of insect species in Huping Mountain Natural Reserve was investigated during 2002-2003. The insect specimens were collected by means of sweeping and gathering on the sample lines. Two samples, each with 100 nets, were collected in every sample plot. Totally 13655 specimens were collected, among them, 5782 belonging to Diptera (42.60% in ratio), 2845 to Hymenoptera (20.96%), 1822 to Homoptera (13.42%), 1357 to Coleoptera (10.00%), 751 to Orthoptera (5.53%), 674 to Hemiptera (4.76%), 151 to Lepidoptera (1.11%), 119 to larvae, and 86 to other insect orders. Three a diversity indices, Simpson index D(dominance), Shannon-Wiener index H'(diversity) and evenness index J, were used to analyze the diversity of insect species of the region. A computer program named Computing System of Diversity Index (CSDI) was developed to cope with the great number of data. The program improves the efficiency and precise degree of computing index in our research. Those obtained indices and the changing tendency were compared by using Excel and SPSS. The affecting factors were grouped into three: environmental factors, collecting time and artificial factors. The results and conclusions are: 1) there are not significant differences between the first and the second samples sweeping in the same site on the computations of indices; 2) it is confirmed that dominance, diversity and evenness of insect species in Huping Mountain do not dramatically change as the variation of altitude gradient; 3) diversity of insect species is low in the evergreen broadleaved forest belt and high in the evergreen broadleavcd and deciduous broadleaved mixed forest belt with the altitude gradient of 1500 meters or so; 4) it is proved that disturbance of human conspicuously changed the community structure of insects and original community of insects of reserve in natural situations which are substituted by species of insects highly related to human activity when comparing and analyzing diversity of insect species at local slope aspect; 5) the affection of anthropic factors on local insect community manifests mainly on developing mountains, building roads and embarking on agricultural actions; 6) the time rank of diversity index is July, August, June, September (from high to low); the order of dominance index is June, August, July and September (from high to low); and there are not obvious differences on index of evenness except the higher value of July when time is discussed. There are many factors that affect the diversity of insect species, in which phytocommunity is the more important one. Altitude, month, exposure and anthropogenic factor affect occurrence and distribution of insects and further change species diversity of insect community by changing appearance of phytocommunity and microenvironment of habitat such as temperature, moisture and light. Compared with the former researches, this study may have more time span, more collection times, more extensive and comprehensive range, and higher precision. Furthermore, it provides a research system appropriate for computing a large amount of indexes, which supplies with more abundant referencable basic data and credible instruments for discussing researches, assessments and monitor of community diversity of insect in mountainous regions in future.
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