【摘要】 采用盆栽试验,通过对锰尾矿区、恢复区和模拟锰污染土壤中加入不同质量摩尔浓度的抗坏血酸、酒石酸和EDTA,研究加入螯合剂对超富集植物短毛蓼累积土壤中锰的影响。结果表明:短毛蓼对不同土壤中锰的累积效果有很大不同,添加螯合剂能显著提高短毛蓼对尾矿区和恢复区锰的累积,却抑制了其对模拟区锰的吸收;EDTA对提高短毛蓼富集、转运土壤中锰的影响明显大于抗坏血酸和酒石酸,其中,10 mmol/kg EDTA对尾矿区短毛蓼地上部富集能力的影响达到了最大;植物对重金属的迁移总量与地上部生物量有密切关系,而螯合剂对植物有一定毒害作用,如果浓度过高会严重影响植物的产量,如10 mmol/kg EDTA使地上部的生物量减产过半。总的来说,不同浓度的不同螯合剂对短毛蓼累积锰的调控效应各不相同,从修复潜力和潜在的环境风险来看,5 mmol/kg EDTA是提高锰尾矿区短毛蓼对锰的转运能力和修复效率的最佳调控螯合剂。更多还原

【Abstract】 With pot experiment,the effect of removing manganese in soil by planting the hyperaccumulator Polygonum pubescens Blume is studied in this paper,through adding chelating agents of different mass molar concentrations such as ascorbic acid,tartaric acid and EDTA to the soil from manganese ore tailings area and restoration area and the simulation area for research of manganese pollution.Results show that for different soil types,the accumulation effect of P.pubescens to manganese show great diversity,which can be significantly improved in manganese ore tailings area and restoration area by adding chelating agents to the soil,while in simulation area it is restrained.Compared with ascorbic acid and tartaric acid,EDTA has a better effect on P.pubescens’s cumulation for manganese.When the concentration of EDTA reaches 10 mmol/kg,the accumulation capacity of P.pubescens’s shoot gets the maximum value.The cumulation capacity of plants to heavy metal has a close connection with the phytomass.To a certain degree,chelating agents are poisonous to plant,high concentration of which will seriously affect plant yield.Overground parts of plant will decline more than 50% when EDTA concentration amounts to 10 mmol/kg.Generally speaking,P.pubescens’s cumulation effect for manganese differs by adding different chelating agents of different concentration.In regard of remediation potential and latent environmental risk,EDTA is the best chelating agent for the restoration of manganese ore tailings by planting P.pubescens and the removal efficiency of manganese is optimum when the concentration of EDTA is 5 mmol/kg.更多还原