Composition and Distribution of Soil Spider Assemblages in Three Natural Secondary Forests in Ziwuling, Gansu

Soil spiders were pitfall-trapped once every month in three forest vegetation types of Ziwuling natural secondary forest region, Gansu Province from April to October, 2004. A total of 2164 spiders were collected, belonging to 43 species in 19 families, captured in 630 pitfall trap collections. Linyphiidae, Gnaphosidae and Lycosodae were found to be the dominant families in all habitat types, and the composition of soil spider assemblages was different between the three habitats. Ecological indices of diversity, richness and evenness were significantly different between the three habitats (P<0.05). The relative abundance of guilds (based on numbers of individuals) varied greatly (P<0.01), which may reflect resource availability within habitat types. The existence of different patterns within the assemblages reflects the importance of maintaining habitat heterogeneity and vegetation types in order to preserve soil spider biodiversity.