Cd、Zn、Pb单因素及复合污染对土壤酶活性的影响

通过Ｃｄ、Ｚｎ、Ｐｂ单因素处理和复合因素处理的对比性研究发现，无论是单因素或复因素对土壤酶活性的抑制效应顺序均为 Ｃｄ＞ Ｚｎ＞ Ｐｂ；在所研究的 ４种土壤酶中，脲酶受重金属的抑制作用最为敏感； Ｃｄ、 Ｚｎ、 Ｐｂ复合污染与各单因素的影响有较大差异，同时，Ｃｄ、Ｚｎ、Ｐｂ复合污染对４种土壤酶活性的影响效应亦不同。其复合污染对脲酶表现出协同抑制负效应的特征；对过氧化氢表现出一定的屏蔽作用或拮抗作用；转化酶和碱性磷酸酶主要因Ｃｄ浓度的变化而变化。

Effects of Single Element and Compound Pollution of Cd, Zn and Pb on Soil Enzyme Activities

By comparing Cd, Zn ac Pb single element with compound pollution in the experiment, the effects of Cd, Zn and Pb on soil enzyme activities are studied. The results show that the inhibiting effects of Cd, Zn and Ph single element as well as their compound pollution on soil enzymes have a toxicity order: Cd>Zn>Pb. In the four studied soil enzymes, Urease is the most sensitive to the inhibition of heavy metals. Effect of Cd, Zn and Pb single element on soil enzymes is different from that of Cd-Zn-Pb compound pollution. Meanwhile, influence of Cd-Zn-Pb compound pollution on the four soil enzymes is different too. The characteristics of Cd-Zn-Pb compound pollution for urease exhibites synergistic inhibition effect. The three-element compound pollution for catalase activities exhibites protective effect to some extent. Under the combination of Cd-Zn-Ph, invertase and phosphatase changes significantly, mainly with the changing contents of Cd.