为了研究膨润土对铜污染土壤的修复机理，通过油菜盆栽试验研究了粘土矿物膨润土对铜污染土壤酶活性的影响。结果表明：随着铜污染程度的增加，土壤脲酶、碱性磷酸酶、过氧化氢酶、硝酸还原酶的活性都受到不同程度的抑制。膨润土的施加能显著提高铜污染的土壤酶活性，土壤脲酶、碱性磷酸酶、过氧化氢酶、硝酸还原酶的活性分别提高了6.4%~15.4%、4.0%~19.3%、1.26%~1.85%和4.6%~10.9%，且对4种酶活性的增加幅度为：碱性磷酸酶>脲酶>硝酸还原酶>过氧化氢酶，并表现出在高污染下对土壤脲酶和碱性磷酸酶的增幅大于低浓度污染，在低浓度污染下对土壤过氧化氢酶和硝酸还原酶的增幅大于高浓度铜污染。说明膨润土对铜污染的土壤有一定的修复能力。

In order to study on the remediation mechanism of bentonite on copper contaminated soil, a pot experiment of rape was conducted to study the effects of clay minerals about bentonite on soil enzyme activity of copper contaminated soil. The results showed that: activities of urease, alkaline phosphatase, catalase and nitrate reductase in soil were significantly restrained with increase of concentration of copper in contaminated soil. Bentonite significantly increased activities of urease, alkaline phosphatase, catalase and nitrate reductase by 6.4%-15.4%, 4.0%-19.3%, 1.26%-1.85%, 4.6%-10.9% in the copper contaminated soil, respectively and the increase rates of 4r enzyme activity were in order: alkaline phosphatase＞urease＞nitrate reductase＞catalase. Increase rates of urease and alkaline phosphatase activities were greater in high concentration copper contaminated soils than in the low concentration of copper contaminated soils, but catalase and nitrate reductase activities were greater in low concentration than in high concentration of copper contaminated soils. Therefore, bentonite could amend copper contaminated soils.