三峡建坝后江汉平原土壤含水量及气温对钉螺生态的影响

IMPACT ON SNAIL ECOLOGY BY SOIL HUMIDITY AND TEMPERATURE IN JIANGHAN PLAIN AFTER THE THREE GEORGES DAM PROJECT

目的 了解三峡建坝后长江水位的变化 ,引起地下水位、土壤含水量、气温等因素变化对钉螺生态的影响程度。方法 采用调查与实验的方法 ,对钉螺在不同土壤含水量和气温条件下分布与产卵等情况进行观察。结果 在 4月份距水线 0 .33m的环境钉螺分布最多 ;5月份在土壤含水量为 36 .9%的环境钉螺产卵的数量最多 ;春季随着气温逐渐升高 ,钉螺产卵孵出的时间亦随之缩短。结论 三峡建坝后引起的地下水位改变 ,对钉螺生态有一定的影响 。

Objective To investigate and analysis the influence on snail ecology by water level of the Yangtze River, water table, soil humidity and air temperature after the Three Gorges Dam Project.Methods The snail distribution and egg-laying in different soil humidity and air temperature conditions were investigated by means of observation and experiment.Results There were most snail distribution on the environment of 0.33 m from water line in April, and the most eggs-laying on the condition that soil humidity was 36.9% in May. The hatch time of snail eggs became shorter with air temperature grew up in spring. Conclusion The change of the water table will affect the snail ecology in Jianhan Plain after the Three Gorges Dam Project, The measures of snail control according to the change of environment will work out.