不同钝化剂对重金属污染土壤中酶活性、阳离子交换量和矿质元素的影响

Effects of Different Passivators on Enzyme Activity, Cation Exchange Capacity and Mineral Elements in Heavy Metal Contaminated Soil

摘要: 本研究通过室内盆栽试验，研究不同钝化剂及钝化剂+有机肥联合作用对铜、镉、锌和铅四种重金属混合污染土壤中主要的酶活性和阳离子交换量的影响。结果显示，仅添加钝化剂的处理酶活性变化差异不显著；不同有机肥添加量均显著提高土壤中脲酶、过氧化氢酶、磷酸酶和蔗糖酶的含量。高有机肥的ZH、SH和PH处理脲酶含量分别为9.5 NH₃-N mg•g⁻¹、8.3 NH₃-N mg•g⁻¹和8.2 NH₃-N mg•g⁻¹，分别较CK提高了126.2%、97.6%和95.2%；而添加高浓度有机肥处理后土壤中磷酸酶和蔗糖酶表为ZH > SH > PH。不同钝化剂和有机肥处理显著影响土壤中离子的交换量。ZH处理的阳离子交换量最高，为45.8 cmol/kg，较CK (28.5 cmol/kg)提高了60.7%；不同处理对土壤中水溶性的Ca²⁺、Mg²⁺、Na⁺和有效态Si、Fe、Mn均有不同程度的促进作用。综合分析，以高浓度的有机肥有利于提高污染土壤中酶活性、阳离子交换量和水溶性矿质元素的含量。其中以高有机肥+沸石的处理效果最佳。

Abstract: This study investigated the effects of different passivators and the combined effects of passivators + organic fertilizers on the main enzyme activities and cation exchange capacity in soils contaminated with four heavy metals of copper, cadmium, zinc and lead through indoor pot experiments. The results showed that there was no significant difference in enzyme activity in the treatment with only the addition of passivating agent; different organic fertilizers added significantly increased the content of urease, catalase, phosphatase and invertase in the soil. The urease content of ZH, SH and PH treatments of high organic fertilizer were 9.5 NH₃-N mg•g⁻¹, 8.3 NH₃-N mg•g⁻¹ and 8.2 NH₃-N mg•g⁻¹, respectively, which were increased by 126.2 compared with CK. %, 97.6% and 95.2%; and the phosphatase and invertase tables in the soil after adding high-concentration organic fertilizer treatment are ZH > SH > PH. Different passivation agents and organic fertilizer treatments significantly affect the exchange of ions in the soil. The cation exchange capacity of ZH treatment is the highest, 45.8 cmol/kg, which is 60.7% higher than that of CK (28.5 cmol/kg); different treatments promoted the water-soluble Ca²⁺, Mg²⁺, Na⁺ and available Si, Fe, Mn in the soil to varying degrees. Comprehensive analysis shows that high-concentration organic fertilizer is beneficial to increase the enzyme activity and cation exchange capacity in contaminated soil. Among them, the treatment effect of high organic fertilizer + zeolite is the best.