四种改良剂对Cu、Cd复合污染土壤中Cu、Cd形态和土壤酶活性的影响

Effects of four amendments on Cu and Cd forms and soil enzyme activity in Cu-Cd polluted soil

以黑麦草(Lolium perenne L.)作为修复植物进行田间试验,研究了石灰、磷灰石、蒙脱石、凹凸棒石4种改良剂对铜镉复合污染土壤中Cu、Cd形态和土壤酶活性的影响。结果表明,改良剂提高了污染土壤pH,降低了土壤可交换态(EX)Cu、Cd含量;改良剂提高了土壤脲酶、酸性磷酸酶和过氧化氢酶活性,每种改良剂对土壤酶活性增加幅度随其添加剂量增加而增大;土壤酶活性与土壤EX态Cu、Cd含量呈显著或极显著负相关关系,与土壤pH呈显著或极显著正相关关系;高剂量石灰(石灰占污染土壤耕作层质量的0.4%)和高剂量磷灰石(磷灰石占污染土壤耕作层质量的2.32%)处理钝化污染土壤中Cu、Cd及提高土壤酶活性效果最好。

The objective of this study was to investigate effects of lime,apatite,montmorillonite and attapulgite on Cu and Cd forms in soil and soil enzyme activity where perennial ryegrass（Lolium perenne L.） was planted for in-situ remediation.The results indicated that all amendments resulted in an increase in soil pH,but a decrease in the exchangeable Cu（EX-Cd） concentration.The activities of urease,acid phosphatase and catalase in soil was greater for amendment treated soil compared to untreated soil.The level of soil enzyme activity was higher with increasing amount of each amendment.All enzyme activities were negatively correlated with soil EX-Cu and exchangeable Cd,but positively correlated with soil pH.High level of lime（0.4% lime of tillable soil layer） and apatite（2.32% apatite of tillable soil layer） treatments have the best effects of passivation of Cu and Cd in soil,and increasing soil enzyme activities.