【摘要】 为提高植物修复重金属污染土壤的效率。以紫花苜蓿(Medicago sativa L.)为原材料，采用土培盆栽法研究比较了难降解螯合剂EDTA与易降解螯合剂没食子酸(Gallic acid)强化紫花苜蓿修复Cd、Pb污染土壤的修复效能。研究结果表明：两种螯合剂均能有效促进紫花苜蓿吸收土壤中的Cd与Pb,提高植物修复效率。当外源Cd浓度为0～20 mg/kg时，EDTA作用下紫花苜蓿对Cd的提取效率提高了3.56～0.22倍，Gallic acid作用下Cd的提取效率提高了4.2～0.32倍；当Pb的浓度为0～1 000 mg/kg时，施加EDTA后Pb的提取效率提高了1.03～5.01倍，施加Gallic acid后Pb的提取效率提高了0.8～4.99倍。同时研究发现，螯合剂在促进植物吸收富集重金属时会对植物的生长发育产生不利影响，且EDTA产生的毒害作用大于Gallic acid,但因Gallic acid在自然环境中易于降解，不易造成二次污染，故在植物修复领域，Gallic acid的环保应用潜力更大。更多还原

【Abstract】 In order to improve the phytoremediation efficiency of heavy metal contaminated soil.Alfalfa(Medicago sativa L.) was used as raw material to study the effects of EDTA and Gallic acid on remediation of Cd and Pb contaminated soil.The results show that the two chelating agents could effectively promote the absorption of Cd and Pb by alfalfa and improve the phytoremediation efficiency.When the concentration of exogenous Cd is 0～20 mg/kg, the extraction efficiency of Alfalfa for Cd increased by 3.56～0.22 times under EDTA,and 4.2～0.32 times under Gallic acid; when the concentration of Pb is 0～1 000 mg/kg, the extraction efficiency of Pb is increased by 1.03～5.01 times and 0.8～4.99 times by Gallic acid.At the same time, it is found that chelating agents will have adverse effects on the growth and development of plants when they promote the absorption and enrichment of heavy metals, and the toxic effect of EDTA is greater than that of Gallic acid.Because Gallic acid is easy to degrade in the natural environment, it is not easy to cause secondary pollution.Therefore, in the field of phytoremediation, Gallic acid has greater potential for environmental protection.更多还原