东至县七里湖江外滩钉螺及阳性钉螺分布的研究

DISTRIBUTION FO SNAIL AND INFECTED SNAIL IN THE YANGTZE RIVER BEACH OF QILI LAKE, DONGZHI COUNTY

采用本统抽样法，调查了乐至县七里湖江外滩钉螺及阳性可螺的分布状况。结果表明，芦滩活螺密度及活螺框出现率明显高于早滩、柳林滩及杉不意杨滩；退垦还滩２０年的芦滩和草滩钉螺密度及活螺框出现率仍低于历史芦滩和草滩，但同时退垦的芦滩活螺密度及活螺框出现率明显高于草滩；阳性钉螺的分布与滩地野粪污染程度有关。上述结果为滩地综合治理提供了科学资料。

The distribution of snail and infected snail was surveyed by way of spetemstic sampling in the beaCh of the Yangtze River in Qili Lake, Dongzhi County. The results showed that the positive rate of frame (0. 11m2) with living snail and the snail density in reed land were higher than in any other vegetation land, such as grass land, willow woods land etc', and that in reed and grass land which had neVer been reclaimed were higher than in new reed and grass land which had been reclaimed 20 years before, and that in new reed land were higher than in new grass land, and that the distribution of infeCted snail was related to the faecal contamination of land.The results will provide scientific foundation for the snail control in the beach.