目的了解洞庭湖移民建镇地区1996年以来溃垸前、后钉螺情况。方法对4个溃垸的有螺地点进行纵向调查,采用系统抽样结合环境抽查方法查螺,5m×5m设框,钉螺鉴定死活后,解剖镜下判定感染螺。结果垸外每年查螺14万m2,活螺框出现率16.25%,钉螺感染率1997年低于1996年洪水后,2000,2003年螺情与1996年基本相近。垸内,每年查螺20万m2,调查880框,无感染螺。活螺密度比溃垸前低或查不到活螺。结论溃垸后垸内钉螺面积均有不同程度的扩散,有必要对螺情进行严密监测。 Objective To understand the situation of snails before and after collapse of embankment in Dongting Lake since 1996. Methods Longitudinal investigation was conducted on four snail embankment sites. Sampling was conducted by systematic sampling combined with environmental sampling method. After identification of 5m × 5m box and identification of snails, the infected snails were determined by dissecting microscope. The results of the embankment check snail 140,000 m2 per year, living screw frame rate of 16.25%, snail infection rate in 1997 was lower than in 1996 after the flood in 2000 and 2003, the snail almost the same as in 1996. Embankment, the annual snail 200,000 m2, investigation 880 boxes, no infection spiral. Live spiral density than the collapse before embankment low or check the live snail. Conclusions After the embankment embankment within the snail area have varying degrees of proliferation, it is necessary to carry out close monitoring of the snail.