南水北调东线一期工程实施后水流水势变化对钉螺北移的影响

目的了解南水北调东线一期工程实施后水流水势变化对钉螺北移的影响。方法调查南水北调东线一期工程实施前后调水量、水流、水位资料,比较分析工程实施后水流水势变化及对钉螺北移扩散的影响。结果南水北调东线一期工程实施后比江水北调现状计划增加抽江水量38亿m3,增调水量主要在10月至次年5月,枯水期增调水量占78.51%~92.36%。一期工程输水规模扩大,但输水河道输水水位基本不变。夹江、芒稻河等水源河道钉螺面积为255.96hm2,阳性钉螺面积为8.27hm2;输水河道钉螺面积为2.09hm2。GPS定位调查表明输水河道钉螺局限分布在里运河高邮段,西岸钉螺分布北端位于北纬32°54.076′,东岸钉螺分布北端位于北纬32°53.293′。结论东线一期工程实施后枯水期调水量增加,避让了汛期钉螺漂流扩散的风险;冬春季输水河道长时间维持高水位可抑制钉螺的繁殖,因此南水北调东线一期工程实施后水流水势变化未明显增加钉螺漂流北移的风险。

Impact of water flow on transmission towards north of Oncomelania hupensis after the first phase of the east route of South-to-North Water Diversion Project

Objective To understand the impact of the water flow on the transmission towards north of Oncomelania hupensis after the first phase was implemented in the east route of South-to-North Water Diversion Project. Methods The volume of water diversion, the flow direction and the water level were investigated before and after the first phase project being finished. The impact of the water flow on the transmission towards north of the snails after the first phase was studied. Results The volume of water diversion from the Yangtze River should be increased by 3.8 billion m3 after the first phase project. These increased water volume from the October to May of the next year, and the increased water should be 78.51%-92.36% in the low-water period. The change of water level should be slight in the water-transporting channel after the first phase project. There were the snail areas of 255.96 hm2 and the infected snail areas of 8.27 hm2 in the waterhead riverway. There were the snail areas of 2.09 hm2 in the water-transporting riverway. The snails in the water-transporting riverway were stable at the Gaoyou segment along the Grand Canal. Conclusion The risk of the transmission towards north of Oncomelania hupensis is not increased by the impact of the water flow after the first phase is implemented in the east route of South-to-North Water Diversion Project.