洪湖东分蓄洪区黏性土淋滤水质试验研究

Leaching experiment on water quality of vadose clay in eastern flood storage area of Honghu Lake

为分析洪湖东分蓄洪区在分洪条件下,洪水对地下水水质的影响,采集了蓄洪区4组有代表性的包气带原状土样在室内开展了淋滤试验以分析滤出液中污染物浓度的变化规律。试验分析结果表明:洪湖分蓄洪区包气带黏性土对硝酸盐和K+有一定的吸附性,不同土质吸附性能也不同;而Ca2+、Mn2+、Cu2+、Pb2+主要表现为解吸作用,从土壤中解吸出来进入下伏含水层,导致地下水硬度增大和重金属污染加重。分蓄洪区蓄洪后,地下水污染加重这一现象应引起相关部门密切关注。

In order to analyze the influence of flood diversion on underground water quality,4 groups of typical undisturbed soil samples were taken in the vadose zone of eastern flood storage area of Honghu Lake and an indoor leaching experiment was conducted to analyze the variation law of pollutant concentration in the leaching liquid. The experiment indicates that the vadose clay in flood storage area of Honghu Lake could absorb nitrate and K^＋ to some degree and the absorbability differs in different soil; but other ions such as Ca^2 ＋、Mn^2 ＋、Cu^2 ＋、Pb^2 ＋mainly dissolve into the quaternary aquifer,leading to groundwater hardness augment and heavy metal pollution,which should be focused after the impoundment of the flood storage area.