添加钠基蒙脱石对重金属污染红壤的影响  

Effects of Adding Na-montmorillonite on Red Soil Polluted by Heavy Metals

作　　者：林云青[1,2] 章钢娅[1] 龚华[1] 

机构地区：[1]土壤与农业可持续发展国家重点实验室中国科学院南京土壤研究所,江苏南京210008 [2]中国科学院研究生院,北京100049

出　　处：《安徽农业科学》2009年第21期10090-10092,10114,共4页Journal of Anhui Agricultural Sciences

基　　金：国家重点基础研究发展规划(973)项目(2007CB936604);中国科学院知识创新工程重要方向项目(KSCX2-YW-N-38)资助

摘　　要：[目的]研究添加钠基蒙脱石对重金属污染红壤中Cu、Zn、Pb和Cd的改良效应。[方法]以采自江西贵溪铜尾矿污染红壤为样品,通过室内恒温培养试验,设5个处理(添加钠基蒙脱石0、1%、2%、4%、8%),测定处理后各样品的土壤有效态重金属含量、水浸提液的Na+、电导率及pH值,分析它们之间相关性。[结果]添加4%和8%的钠基蒙脱石能显著降低重金属污染红壤中有效态Cu、Zn、Pb和Cd的含量,与对照相比,分别降低33.8%和40.2%、33.2%和37.2%、28.4%和32.7%、35.7%和34.5%;随钠基蒙脱石添加量的增加,土壤水浸提液的Na+和电导率以及土壤的pH值逐渐升高。[结论]钝化机理分析表明,重金属污染土壤添加钠基蒙脱石使土壤的pH值升高,增加土壤的吸附性能,使重金属离子与钠基蒙脱石中的Na+发生了置换反应。[ Objective ] The purpose was to study the modified effect of Na-montmorillonite on Cu, Zn, Pb and Cd in heavy metal polluted red soil. [ Method] In the indoor experiment by constant temperature culture, with polluted red soil from the Guixi Copper Tailings in Jiangxi Prov- ince as samples, 5 treatments of adding 1%, 2%, 4% and 8% Na-montmorillonite and non-adding Na-montmorillonite were set up, the available heavy metal, Na^＋ in water extract, electric conductivity and pH in soil from each sample were measured and their correlations were analyzed. [ Result] Adding 4% and 8% Na-montmorillonite could significantly decrease the contents of available Cu, Zn, Pb and Cd in heavy metal polluted red soil, being 33.8% and40.2%, 33.2% and 37.2%, 28.4% and 32.7%, 35.7% and 34.5% lower than that in CK, resp ectively. Na^＋ in water extract, electric conductivity and pH in soils was gradually increased with the increase of Na-montmorillonite adding amount. [ Conclusion ] Analysis on the passivation mechanism showed that the addition of Na-montmorillonite in heavy metal polluted red soil could rise the pH value of soil and increase its adsorption properties, which made the heavy metal ions produce replacement reaction with Na^＋ in montmorillonite.

关 键 词：钠基蒙脱石 有效态重金属 Na+ 电导率 

分 类 号：X53[环境科学与工程—环境工程]