摘要:土壤重金属污染问题日益严重,铬污染是其中之一,植物修复技术是目前应用较多的一类土壤重金属污染修复技术。菌根可以促进植物对重金属的提取与富集,生物降解螯合剂可以减弱重金属与土壤的固定从而促进菌根植物对重金属的吸收,我们可以将二者有效的结合起来辅助植物修复土壤重金属污染。本实验在27种真菌发酵液和三种螯合剂中筛选出Cenococcum geophilum(Cg)菌的菌液为最佳螯合剂,并借助盆栽实验、根袋实验,比较了植物生长状况,测定了植物地上部、地下部干重、以及根际区土壤中脲酶、酸性磷酸酶活力等指标。研究表明,重金属铬可以明显抑制植物生长;菌根化或螯合剂处理可以促进植物对可溶态铬的吸收从而提高植物修复效率,但重金属污染较严重的土壤可能会对修复植物造成一定程度的损害;两者的协同促进作用则更加明显。28114
关键词:菌根植物;生物降解螯合剂;Cr污染;联合修复
Study on the remediation of Cr contaminated soil by mycorrhizal plants and biodegradable chelating agents
Abstract:Heavy metals pollution in soilsis becoming increasingly serious. Chromium pollution is one of the types of heavy metal pollution in soils.Phytoremediation is one of the most widely used techniques for soil heavy metals pollution remediation.Mycorrhizae can promote plants to absorb heavy metals in soil and enrich them in plants.So we can repair the heavy metal pollution in the soil by removing plants.Mycorrhiza can promote the extraction and enrichment of heavy metals in plants.Biodegradable chelating agents can reduce the immobilization of heavy metals and soil which can promote the absorption of heavy metals by mycorrhizal plants.Therefore,it can effectively repair heavy metal pollution in soil by means of plants.In this experiment, 27 strains of fungus fermentation liquid and the three kinds of chelating agents were selected.The fungus fermentation liquid of Cg is the best chelating agent.With the method of pot experiment and root bags experiment, the form of plant samples was compared, and the length of root and shoot were measured.The experiment also included determining of urease and acid phosphatase activity in the matrix.The result can prove that that heavy metals can significantly inhibit the growth of plants.Mycorrhizal or chelating agent can promote plant uptake of soluble chromium so as to improve the efficiency of phytoremediation.but serious heavy metal pollution in soil may cause some degree of damage to repair plant.The effect of combined treatment of mycorrhiza and chelating agent was better than any one of them.
Key words:Mycorrhizal plant;Biodegradable chelating agents;Chromium pollution;Remediation
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