Studies Of Diversity Of Butterflies Community In North Luo-River Of Yanan

Diversity of butterflies community in North Luo-River of Yanan are investigated and studied by using Fauna, species-abundance model, diversity index and clustering and so on in this paper. The results are as follows:1.This experiment has collects 4056 butterflies, subiect to 6 families 54 genera and 75 species i.e. Papilionidae 2 genera and 3 species, Pierdae 7 genera and 10 species, Satyridae 10 genera and 13 species, Nymphalidae 15 genera and 25 species, Lycaenidae 11 genera and 15 species, Hesperiidae 8 genera and 9 species. Among them, 34 species were single species of single genera, 5 species were first recorded in Shannxi Province.2. The distribution of butterfly is very uneven in this area. The Palaercyic species 36 species occupies 48.0%, the Oriental species 4 species occupies 5.3%, and the widespread species 35 species occupies 46.7%. Pieris rapae,Polyommatus eros and Colias erate are the dominant species in this area, which occupies 42.0% in total.3. The variational trend of diversity index in different months is the following: H is July﹥August﹥September﹥May;The trend of R, PIE and E are the same as H; Dm reflects the dominance of species, so its trend is opposite to H. Namely, May﹥September﹥August July. The variational trend of diversity index in different sites is the following: H is Fuxian﹥Luochuan﹥Ganquan﹥Zhidan﹥Huangling﹥Wuqi; The trend of R and PIE are the same as H; The variational trend of E is Luochuan﹥Fuxian﹥Ganquan﹥Zhidan﹥Huangling﹥Wuqi; The trend of Dm is opposite to H. Namely, Wuqi﹥Huangling﹥Zhidan﹥Ganquan﹥Luochuan﹥Fuxian. The variational trend of diversity index in different habitats is the following: H is woodland﹥grassland﹥riverside and road﹥farmland; The trend of E and PIE are the same as H; The variational trend of R is grassland﹥riverside and road﹥Woodland﹥farmland; The trend of Dm is opposite to H. Namely, farmland﹥riverside and road﹥grassland﹥Woodland.4. The species-abundance model of different months, sites and habitats all match baxically to Preston's lignormal distribution. This distribution has been hoped to appear in many communities. It reflects the constructive composing of butterfly community and the principle that many species coexist in the community. Namely, the dominant and rare species are few, and the species in the intermediate state are rich comparatively。5. The clustering results of different months show that similarity of August and September is the highest, July and August is the higher; The clustering results of different sites show that similarity of Luochuan and Huangling is the highest,Wuqi and Zhidan is the higher, Fuxian closes to Luochuan and Huangling; The clustering results of different habitats show that similarity of grassland and riverside and road is the highest, another habitats are fewer.6. The results of PCA to climate factors and butterfly community of different sites show: the cumulative percent of principal components of climate and butterfly community of different sites reach respectively 94.459% and 100.000%, which also occupy mass information and may represent the characteristics of the whole community. The results of PCA are very ideal.7. The results of stepwise regression to climate factors and butterfly community show: the climate factors affecting the species and numbers of butterfly are the highest temperature uttermostly, the highest precipitation of May to September, the lowest precipitation of May to September, accumulated temperature of exceed or equal to 10℃and time without frost et al.