The Springer and Summer Spiders\' Diversity and Its Formation Mechanism in Mountains of Northwest of Jiangxi

• 1、Department of Biology, East China University of Technology, Nanchang 330013
• 2、College of Life Science, Gannan Normal University of Technology, Ganzhou 341000

Abstract：Spiders are important nodes in the food chain or web of plants and insects. It is important to study the diversity of spiders in order to reveal the stability of agro-forestry ecosystem structure and the energy and material cycle. This survey on spider resources and fauna in spring and summer of the Yunjushan of Yongxiu county（A）, the Yangshan of Fengxin county（B）, the guanshan of Yifeng county（C）,the Mingyueshan of Yichun city（D）, the Wugongshan of Pingxiang city（E）and the Dagangshan of Xinyu city（F）, all of which located in the northwest of Jiangxi province, had obtained 2232 copies of spider specimens. It was discovered by classification and identification that they were attached to 20 families, 96 generas and 169 species, of which 19 species were new records of Jiangxi and 55 species were undetermined. Through the comparative analysis of spider species, community structure and predation function diversity index, as well as the cluster analysis of community similarity and the statistical analysis of the action factors of regional characteristic species, this paper focuses on the characteristics and formation mechanism of spider diversity in summer and autumn in this area. A cluster analysis of the similarity of its spider community showed that the similarity between these mountains was A=B-C-D=E-F. A statistical analysis on formative factors of endemic species\' diversity showed that the community structure richness, the predation functional dominance, the predation functional diversity, and the predation functional richness were four main factors affecting their diversity forms in those mountains of northwest Jiangxi, and there was a common relativity between these index variables. The diversity of spiders of crypt type, surface type, network type and vagabundae type were respectively affected by heterogeneity of ground surface (topography), plant debris cover, vegetation vertical structure and vegetation horizontal structure. Additionally, functional diversity is associated with availability and abundance of prey. In short, the typical tropical forest vegetation, a high landscape heterogeneity degree and the abundant moisture in Poyang Lake and Ganjiang from their northeast resulted in the relevance in diversity of spiders in different mountains. Moreover, the difference in height, distance, vegetation and moisture condition, and human disturbance degree between these mountains guided respectively the formation and exchange for their spider community structure and prey functional diversity. As a result, endemic spiders take an occupying proportion among all spider species during spring and summer in the mountain areas of northwest Jiangxi. There exists a small amount of other common species in agricultural and residential areas as well.

Keywords： the southwest of Jiangxi；mountains；spring and summer；spider；diversity；community structure predation function.