In order toeliminate the potential harm of heavy metal contaminants to human health in the soil and meet the requirements of the subsequent development of the site after restoration, the soil near the waste residue field of lead-zinc mine in Huiyang district was selected as the research object. Mineral amendment was synthesized with a variety of ingredients (mainly are Ca2Al2SiO7, Ca2MgSi2O7, Ca3MgSi2O8) as repair material. The effects of mineral amendment on pH, heavy metal leaching concentration, lead and copper fractions and mineral elements (K, Ca, Mg, and Si) were studied in this paper to provide the basis for restoration of contaminated soil. The results showed that the application of the mineral amendment increased the pH value of 0.33~2.62 units and the sustained effect is better. The stabilization efficiency of amendment to Pb and Cu were up to 100%, when the application rate was 4 g·kg-1. The contents of acid extractable Pb and Cu were reduced by 39.01%~44.2% and 46.71%~53.07%, respectively. It reduced the bioavailability of heavy metals in the soil environment. The addition of mineral amendment increased the content of available K, available Si, exchangeable Ca and exchangeable Mg in the soil. The correlation analysis showed that there was a significant negative correlation between mineral elements content and acid extractable heavy metals in soil (P<0.05). This amendment can inhibition of soil acidification, reduce the bioavailability of heavy metals and have a good remediation effect on lead and copper contaminated soil.%为了重金属污染土壤的修复提供参考,以惠阳区某铅锌矿废渣场附近土壤为研究对象,采用人工合成的含多种成分(主要为Ca2Al2SiO7、Ca2MgSi2O7和Ca3MgSi2O8)的矿物质钝化剂为修复材料,研究其对铅、铜复合型污染土壤pH、重金属浸出浓度、铅和铜的形态及矿质元素(K、Ca、Mg和Si)含量的影响.试验结果表明:该矿物质钝化剂的施用升高了0.33~2.62个单位的土壤pH值,对土壤修复持效性好;在施用量为4 g·kg-1时,钝化剂对Pb和Cu的稳定效率高达100%;钝化剂的施用使弱酸提取态Pb和Cu的含量分别减少了39.01%~44.02%和46.71%~53.07%,降低了重金属在土壤环境中的生物有效性;添加矿物质钝化剂使土壤中有效钾、有效硅、交换性钙和交换性镁的含量增加.由相关性分析可知,矿质元素含量与弱酸提取态重金属之间呈显著负相关关系(P<0.05).因此,该矿物质钝化剂能抑制土壤酸化,降低土壤中铅和铜的生物有效性,对铅、铜复合型污染土壤具有很好的修复作用.
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