Abstract:

Objective To evaluate the snail control effect of a film covering method in fish ponds and ditches. Methods Two fish ponds and 2 ditches with Oncomelania snails were selected as pilots, and 1 fish pond as Group A1 and I ditch as Group B1 received niclosamide spraying + film covering, and another fish pond as Group A2 and another ditch as Group B2 received niclosamide spraying only. The snail control effects were observed at 15, 30, 90 d and 360 d after the test, and the fish and other aquatic were also observed. Results In Group A1, the adjusted mortality rates of snails were 92.31%, 99.36% and 100% at 15 , 30 d and 90 d after the test, respectively; in Group B1, the adjusted mortality rates of snails were 91.45,%, 95.84% and 100% at 15, 30 d and 90 d after the test, respectively; and there was no death of fish. The densities of snails were 0 and 0.07 snails/0.1 m2 one year after the test, respectively. In Group A2, the adjusted mortality rates of snails were 75.36%, 72.59% and 65.76% at 15 d, 30 d and 90 d after the test, respectively; in Group B2, the adjusted mortality rates of snails were 70.36%, 72.87% and 75.82% at 15, 30 d and 90 d after the test, respectively; and there was death of fish. The densities of snails were 0.11 snails/0.1 m2 and 0.13 snails/0.1 m2 one year after the test, respectively. Conclusion In ponds and ditches with snails, the niclosamide spraying + film covering method is very effective and safe.

Key words: Snail, Plastic film, Fish pond, Ditch, Snail control effect

摘要：

目的 评价薄膜覆盖法杀灭鱼塘及周边沟渠环境钉螺的效果。方法 选择有螺鱼塘及周边有螺沟渠， 分别采用 “氯硝柳胺药物喷洒+薄膜覆盖”（“药物+覆膜” 法） 和单纯氯硝柳胺药物喷洒 （药物喷洒法） 进行灭螺试验， 并于灭后15、 30、 90 d 和360 d进行灭螺效果观察； 同时观察灭螺现场的鱼类等水生动物死亡情况。结果 “药物+覆膜” 法在鱼塘和沟渠环境15、 30、 90 d的钉螺校正死亡率分别为92.31%、 99.36%、 100%和91.45%、 95.84%、 100%， 未发生鱼类死亡现象， 1年后活螺密度分别降为0和0.07只/0.1 m2 ； 而单纯药物喷洒法在两种环境中的钉螺校正死亡率分别为75.36%、 72.59%、 65.76%和 70.36%、 72.87%、 75.82%， 且有鱼类等水生动物死亡， 1年后的活螺密度分别为0.11只/0.1 m2 和0.13只/0.1 m2 。结论 在鱼塘及周边沟渠特殊有螺环境， 应用 “药物+覆膜” 法， 既可显著提高灭螺效果， 又可有效避免药物灭螺对鱼类等水生动物的毒性影响， 值得推广应用。

关键词: 钉螺；塑料薄膜；鱼塘；沟渠；灭螺效果