酸雨对Cu在长三角地区4种典型土壤中的解吸影响

Desorption of copper by citric acid in the different parent material soils of Yangtze River delta

主要研究在不同环境条件下,长江三角洲地区不同母质发育土壤中铜解吸规律.试验采用具有代表性的长江三角洲地区4种母质发育而成的土壤,加入外源铜培育污染土样,以不同pH酸雨为解吸液对污染土样进行解吸.结果表明:随着酸雨的加入,已污染土壤中Cu的解吸量增加;在酸雨pH相同时,酸雨对Cu的解吸量与污染土样中Cu含量呈正变关系;在已污染土壤中Cu含量相同时,Cu的解吸量随着酸雨pH的下降而增加.比较不同母质发育而成的土壤,在pH=3.0、4.0、5.6时,已污染土壤中Cu的解吸量由强到弱的顺序为:沟沟堆积母质、湖相沉积物母质、河相沉积物母质,海相沉积物母质.在pH=2.0时,河相沉积物母质、海相沉积物母质Cu的解吸量增加迅速.

The desorption of copper under different conditions in four kinds of typical soils formed by different parent materials in Yangtze River delta was studied.The soils polluted by the copper were desorbed by acid rain.The result revealed that the acid rain could promote the desorption of the copper and the desorption of the copper in polluted soil was enhanced with the pH decreasing of the acid rain.For different parent material soils,the desorption of the copper by the acid rain with pH of 3.0,4.0 and 5.6 followed the order： depositlake sedimentriver sedimentsea sediment.In the river sediment and the sea sediment,the desorption of the copper by acid rain with pH of 2.0 increased rapidly.