三峡建坝后长江安徽段江洲滩变化趋势及其对血吸虫病流行的影响

本文根据长江水利委员会提供的三峡建坝后长江安徽段来水来沙变化和冲淤情况，结合安徽段河道、江洲滩现状和血吸虫病流行的状况调查，分析论证了三峡建坝后长江安徽段河道冲淤变化及其对血吸虫病流行的影响。结果显示，三峡建坝后来水变化对长江安徽段河道影响不大，来沙变化对下游影响较大，水库建成后１～８０年内安徽段河道一直处于淤积势态，支流淤塞，滩地面积可能会有所增加。现况调查结果显示，目前皖江段涨滩明显，６年内涨滩１４７９．８万ｍ２，建坝后水沙变化可能进一步促使滩地增长。据涨滩后生长植被，然后孳生钉螺的规律，预测三峡建坝后长江安徽段江洲滩地区钉螺面积可能会有所增加

THE CHANGE TENDENCY OF BEACH AND ISLET IN ANHUI SECTION OFTHE YANGTZE RIVER BY THE THREE GORGES RESERVOIR ANDITS INFLUENCE ON TRANSMISSION OF SCHISTOSOMA JAPONICUM

The change tendency of beach and islet in Anhui section and its influence on transmission of Schistosoma japonicum were analyzed and discussed. Predictive data of water level and sedimentation in Anhui section of the Yangtze River after building the Three Gorges Reservoir were supplied by Changjiang Water Conservancy Committee. The general situation of Anhui section of the Yangtze River and schistosomiasis were surveyed. The results showed that the fluctuation of water level would have little influence on channel pattern of Anhui section. But the variation of silt would lead to great changes in the channel pattern, The river sedimentaiton in Anhui section would continue deposit within 80 years after building the reservoir. The silts in minor channels would be easier to deposit. The areas of islets would possibly increase consequently. The results from field investigation showed that the area of islets increased rapidly in Anhui seciton at latest several years. Annual average areas of growth accounted for 2 466 000 square meter. The variations of water level and sedimentation would accelerate the growth of beach and islet. It is quite possible that the area of snail distribution will be increased as the increase of the area of the marshlands and variegation.