Investigation On Relationship Between Species Diversity Of Land Snails And Environment In Pogang Nature Reserve And Xianheping National Forest Park In Guizhou, China

In this paper, based on the relationship between species diversity of land snails and environment, the impacts of different environmental factors - season, soil, community, and so on - on the distribution of land snails from Pogang Nature Reserve and Xianheping National Forest Park, Guizhou, China, were discussed. The possible distribution actuality of land snails in these areas was searched as well.Three sampling sites were selected in Pogang Nature Reserve, namely: Jianxie- quan, Yangping and Rongnan. Within each site, random sampling was carried out in different habitats - forest covered by good vegetation, bushes and farmland. Five samples (20cm×20cm) in a 5m×5m random sample were set according to the diagonal sampling method. Larger specimens were collected within each site during the fieldwork. Smaller specimens were extracted from litter and surface soil (depth from 3 to 5cm) by using mesh sieves with apertures between 2mm and 0. 5mm. Individuals and species of land snails in different kinds of habitats were analyzed comparatively. In Xianheping National Forest Park, five sampling sites -Xianheping, Rongjiang, Ronghua, Tiantangshan and Luoshuidong- were sampled in different altitudes with the same methods that had been applied in Pogang Nature Reserve. Additionally, researches were processed in two months in May and October in 2005 for exploring the possible relationship between season and distribution of land snails.In Pogang Nature Reserve, a total specimens of 5,536 land snails were collected, which belong to 57 species (including 14 undefined species), 32 genera, 14 families and 2 subclasses. And a total specimens of 6,925 land snails were collected, which belong to 73 species (including 18 undefined species), 35 genera, 16 families and 2 subclasses in Xianheping National Forest Park.In Pogang Nature Reserve, the main element of fauna was Oriental realm that were 47 species occupying 87.04% of the total, among these there were 2 species distributing only in South-western China district, 8 species distributing only in Southern China district and 9 species distributing only in Central China district. The element of Palaearctic realm was zero and Carychium sibiricum was a world-wide distribution species. While in Xianheping National Forest Park, the main element of fauna was Oriental realm that were 56 species occupying 84.85% of the total, among these there were 8 species distributing only in South-western China district, 10species distributing only in Southern China district and 8 species distributing only in Central...