三峡建坝后湖北监利县长江干流河道变化与钉螺动态的预测研究

三峡建坝后因水位泥沙的变化将导致坝下河道河势改变，从而影响长江中游江滩钉螺的消长，通过回顾性调查及现场观测，对监利县在建坝后的河道变化及钉螺消长作出前瞻性预测，结果证明地处下荆江的监利县在建坝20年内，河道以淤积为主，河床将淤高0.26m，河道则淤窄67m，从而使江滩面积较建坝前增加9.04km2，这有可能成为新的钉螺孳生地，为此提出以截弯取直的水利工程和大坝的适时调度，以及江滩综合治理等防治对策，以防止因建坝带来血吸虫病扩散的不良后果。

Forecast of the River way Change and the Distribution of Snails after Construction of Sanxia Dam of Yangtze River in Jianli County of Hubei Provence

The change in water level and silt after construction of Sanxia dam would result in the changes in the river way and the river bank down reaches of the dam, which would influence the distribution of On- comelania hupensis in river beach of middle and lower of the Yangtze valley. The changes in river way and dis- tribution of snails in Jianli county after construction of dam were prospectively studied by using the reviewed in- vestigation and the field inspection. The results showed that the change of river way was mainly deposit and riverbed should rise 0.26 m in depth and the river way should reduce 67m in width in Jianli county within 20 years of dam construction. Because of the change of river way the areas of riverbeach should increase by 9.06 km2, could result in the formation of a new distributive area of snails. The countermeasures including irrigation works to take out the meanders to add straight of river and management appropriate to dam and harness com- prehensive way to the beach etcetera three prevent countermeasure on the paper for prevent spread of snail.