长江沿线排灌站和船闸引起钉螺向堤内扩散调查

目的分析长江沿线16座排灌(闸)站和1座船闸(以下简称17座闸)闸下钉螺向闸上扩散的原因,为下一步采取有效防控措施提供依据。方法收集整理排灌(闸)站和船闸建成年份、使用时间频度和闸(站)调水功能,采用系统抽样方法结合环境抽样调查闸(站)内外钉螺分布情况。收集排灌(闸)站使用以来的气温、雨量、发生洪水等自然因素情况。结果 17座(闸)站均位于流行区,建于1953—2003年。1998—2008年有记录的15座排灌站引江灌溉累计17164 h,总容量为352005.13万m^3。17座闸下均有钉螺,发现钉螺最早为1956年,最晚为2001年。共调查504万m^2,调查25362框,其中活螺4157框,活螺20607只,活螺平均密度0.81只/0.1 m^2,活螺框出现率16.39%。有4个闸上发现有钉螺,最早于2001年在裕溪船闸,最晚是2008年在汤沟站闸,共调查36万m^2,调查10257框,其中活螺487框,活螺1607只,活螺平均密度0.16只/0.1 m^2,活螺框出现率4.75%。结论钉螺可以通过排灌站或船闸向堤内扩散,但扩散面积小,距离短。通过在排灌(闸)站上下建立拦螺设施和硬化引江渠道,加强对渔船民健康教育和在排灌站周边监测等措施可有效控制钉螺向内河扩散。

Diffusion of snails to embankments by the drainage and irrigation (sluice) stations and locks along the Yangtze River

Objective The causes of snail spreading from 16 drainage and irrigation (sluice) stations to one ship lock along the Yangtze River (hereinafter referred to as 17 locks) are analyzed, and to provide basis for effective prevention and control measures. Methods The construction year, use time frequency and slice(slice station) water transfer function of the discharge and irrigation(sluice) station and lock were collected and sorted out, adopt system sampling method combined with environment sampling to investigate the distribution of oncomelania inside and outside the slice station, etc. Collect natural factors such as temperature, rainfall and flood situation since the use of drainage and irrigation (slice) station. Results All 17 stations were located in epidemic areas. The first one was built in 1953 and the latest in 2003. From 1998 to 2008, a total of 17 164 hours of irrigation were recorded in 15 drainage and irrigation stations, with a total capacity of 3 520 051 300 m³. Brake station outside all had the snail, found that the first snail was 1956, the latest was 2001. A total of 5.04 million m² and 25 362 frames were investigated, including 4 157 live snails and 20 607 live snails. The average density of live snails was 0.81/0.1 m², and the occurrence rate of live snails was 16.39%. Snail situation in the station: snail was found in 4 locks, first in Yuxi lock in 2001, and last in Tonggou lock in 2008. A total of 360 000 m² were surveyed and 10 257 frames were surveyed. 487 frames of live snails, 1 607 live snails, the average density of live snails was 0.16/0.1 m², and the occurrence rate of live snails was 4.75%. Conclusion Oncomelania snails can diffuse into the embankment through irrigation and drainage stations or ship locks, but the diffusion area was small and the distance was short. Effective control measures can effectively control the spread of Oncomelania hupensis to inland rivers by establishing snail facilities and hardening river diversion channels up and down drainage and irrigation stations, strengthening health education and long-term monitoring of fishermen and the surrounding areas of drainage and irrigation stations.