Tang Meng, Zhu Hui-bin, Hu You-ping, Fan Jian-ru, Xu Liang, Luo Feng, Huang Yi, Wu Zi-song
Zhongguo Xue Xi Chong Bing Fang Zhi Za Zhi. 2015 Aug;27(4):406-9.
To master the Oncomelania hupensis snail situation in wetlands surrounding reservoirs in hilly areas in Danling County, Sichuan Province, so as to provide the reference for improving the snail control in these areas.
A medium-sized reservoir (Meiwan Reservoir) and a small-sized reservoir (Zhulinkan Reservoir) were chosen respectively , and the snail situation of the environments surrounding the reservoirs were investigated , the indexes such as the occurrence rate of frames with snails and the density of living snails at the upstream and downstream of the reservoirs as well as the surrounding environments were calculated and compared. Meanwhile , the data of the snail situation of the adjacent villages in the irrigation district at the downstream of the reservoirs year by year were collected to analyze the variation trend.
The Meiwan Reservoir was located in the deep hill, the occurrence rate of frames with snails was 4.29%, the highest and average densities of living snails were 28.00 snails/0.1 m2 and 0.38 snails/0.1 m2, respectively. There was a statistically significant difference between the occurrence rates of frames with snails at the upstream and downstream, which were 0.17% and 22.16%, respectively (χ2 = 1,267.40, P < 0.05), and the rate of spillway was the highest (51.69%). The highest and average densities of living snails in the downstream were 7.00 and 656.10 times higher than those in the upstream respectively. The Zhulinkan Reservoir was located in the shallow hill, the occurrence rate of frames with snails was 17.29%, and the highest and average densities of the living snails were 38.00 snails/0.1 m2 and 0.61 snails/0.1 in 2, respectively. There was a statistically significant difference between the occurrence rates of frames with snails at the upstream and the downstream, which were 12.95% and 50.92% respectively (χ2 = 194.68, P < 0.05), and the rate of spillway was the highest (65.74%). The highest and average densities of living snails in the downstream were 5.43 and 10.00 times higher than those in the upstream respectively. After the construction of the two reservoirs, the snail area in the irrigation districts of the adjacent villages at the downstream was 57.26% of that before and after the construction (398,030 m2/695 160 m2). The snail area showed a down-ward tendency with repeatedly rebound since the 1990s.
The wetland surrounding the reservoir in hilly region is suitable for snail breeding, and the snail situation in the shallow hill is more serious than that in the deep hill. There exists a risk for the repeatability of snail situation in this type of area where the snails can easily diffuse.
掌握四川省丹棱县丘陵地区水库周边湿地的钉螺情况，为改进该地区的灭螺工作提供参考。
分别选取一座中型水库（梅湾水库）和一座小型水库（竹林坎水库），调查水库周边环境的钉螺情况，计算并比较水库上下游及周边环境的有螺框出现率、活螺密度等指标。同时，收集水库下游灌区相邻村庄历年的钉螺情况数据，分析其变化趋势。
梅湾水库位于深山，有螺框出现率为4.29%，活螺最高密度和平均密度分别为28.00只/0.1平方米和0.38只/0.1平方米。上下游有螺框出现率差异有统计学意义，分别为0.17%和22.16%（χ2 = 1267.40，P < 0.05），溢洪道处出现率最高（51.69%）。下游活螺最高密度和平均密度分别是上游的7.00倍和656.10倍。竹林坎水库位于浅山，有螺框出现率为17.29%，活螺最高密度和平均密度分别为38.00只/0.1平方米和0.61只/0.1平方米。上下游有螺框出现率差异有统计学意义，分别为12.95%和50.92%（χ2 = 194.68，P < 0.05），溢洪道处出现率最高（65.74%）。下游活螺最高密度和平均密度分别是上游的5.43倍和10.00倍。两座水库建成后，下游相邻村庄灌区的钉螺面积是建库前后的57.26%（398030平方米/695160平方米）。自20世纪90年代以来，钉螺面积呈下降趋势，但有反复反弹。
丘陵地区水库周边湿地适宜钉螺孳生，浅山地区的钉螺情况比深山地区更严重。在这类钉螺易扩散的地区，存在钉螺情况反复的风险。
