丹阳市不同环境药物灭螺效果

Effects of molluscicides at different environments on Oncomelania hupensis snail control in Danyang City

目的评价在有螺江滩、河道、渠道连续使用氯硝柳胺乙醇胺盐后的灭螺效果。方法选择丹阳市后巷镇北魏江滩、陵口镇肖梁河、云阳镇老庙渠道作为研究现场，采用4％氯硝柳胺乙醇胺盐粉剂50g/㎡和26％四聚杀螺胺（2～4）g/㎡实施灭螺。综合利用历史资料和现场调查资料，评价连续应用灭螺药物后的效果。结果至2013年，北魏江滩、肖梁河、老庙渠道钉螺面积较首次复现时分别下降了82．80％、63．14％和70．00％，钉螺面积与钉螺密度均呈显著正相关（r=0．931、0．975、0．916，P均〈0．05）；灭螺后活螺平均密度较首次复现时下降了92．34％、87．91％和97．66％。灭螺后钉螺校正死亡率与次年活螺平均密度均呈负相关（r=-0．998、-0．999、-0．970）；活螺密度下降率与次年活螺平均密度均呈负相关（r=-0．997、-0.998、-0．868）。结论药物灭螺在压缩钉螺面积、降低钉螺密度、控制血吸虫病传播等方面效果明显．

Objective To evaluate the effects of continuous application of niclosamide ethanolamine salt on Oncomelania hu pensis snail control in a marshland, river and channel. Methods The Beiwei marshland in Houxiang Town, the Xiaoliang River in Lingkou Town and Laomiao channel in Yunyang Town in Danyang City were selected as study sites, and 4% niclosamide etha nolamine salt and 26% niclosamide powder were used to kill the snails. Based on the historical records and field investigations, the effects of continuous application of niclosamide ethanolamine salt on snail control were evaluated. Results Compared with the first time of snail repetition, the snail areas decreased by 82.80%, 63.14% and 70.00% in the Beiwei marshland, Xiaoliang River and Laomiao channel, respectively, in 2013. There was a positive correlation between the area and density of snails （r ： 0.931, 0.975 and 0.916, respectively; all P values 〈 0.05）. The average densities of living snails decreased significantly by 92.34%, 87.91% and 97.66%, respectively. There was a negative correlation between the corrected mortality of snails and the average densi ty of living snails in the following year, and a negative eorrelalion between the reduction rate of living snail density and the average density of living snails in the following year. Conclusion Molluscicides plays an important role in compressing the snail area, re ducing the snail density, and controlling the schistosomiasis transmission.