Oncomelania Distribution Characteristic And Relationship With Environment Factors In The Hilly And Mountains District

This research focuses on the Oncomelania in view of the present need of preventing and controlling Schistosomiasis in China. Hilly and mountainous district with Schistosomiasis in the upstream of the Yangtze River, Yejiang River drainage basin , Renshou Country, Sichuan was chosen. Vegetation, soil environment factors and snails are sampled according to the different land utilization/cover (LUC) types. SPSS and ForStat 2.0 statistical software were applied for analyzing relationship between snail distribution and environment factors. The main results are as follows:1. The mean Oncomelania density is 4.05/0.11 m~2, and the living snail frame occurrence rate is 34% in different land utilization/cover (LUC) types. The regularity for Oncomelania density is paddy fields> irrigation canal > wastelands> beaches > arable lands>forest. Another regularity for the living snail frame occurrence rate is paddy fields> beaches > wastelands> irrigation canal > arable lands >forest.2. The Oncomelania distributes in a certain vegetation and soil environment. In that, the coverage of herb communities is 70%~90%, the mean height is 23cm~30cm, the richness is 8~14, the soil temperature is 18℃~23℃, the conductivity is 120mS/m~150mS/m, the soil water content is 25%~40%.3. 6 Mathematics equations have been developed by analyzing relationship between the Oncomelania density and environment factors:(1) The density of Oncomelania and the richness of the herb communities: y = -0.0594x~2 +...