Abstract:

Three Gorges reservoir area is located between Jianghan Plain and Chengdu Plain,where schistosomiasis is epidemic.Before the dam,the distribution of Oncomelania which is the only intermediate host of schistosoma has never been found in Chongqing segment of the Three Gorges reservoir.However,after the dam,the water flow rate of the Changjiang River and tributaries slows down,sedimentation increases,and alluvial bottomland comes into being.Combined with the suitable climatic conditions,it is likely to cause the breeding and proliferation of Oncomelania which can make the spread of schistosomiasis.In this paper,we developed method to find out the potential breeding region of Oncomelania in the Three Gorges reservoir area based on GIS and RS.Major data used in this study included meteorological data of 56 stations during 1971~2000,hydrological data of the main channel and tributaries of the Changjiang River,and ETM remote sensing data.With the evaluation of refined meteorological element distribution maps,waterlevelfluctuation zone,vegetation and other key ecological parameters,we found the potential breeding region of Oncomelania in the Three Gorges reservoir area,and selected two focus regions of Qukou in Kaixian and Dachang in Wushan for further monitoring.