摘要
利用植物修复尾矿库模型实验装置,对紫穗槐根际不同深度的尾矿土进行分层采样和Cu,Zn,Pb,Cd,Cr 5种重金属检测,分析在不同深度的尾矿土中重金属含量,剖析其纵向迁移规律。分析结果表明,不同深度的根际尾矿土中,Zn,Cu,Cr,Pb含量明显高于Cd,其中,Cd含量均最低,Zn含量均最高;Cr含量随深度的增加呈现先降低后增高的趋势;Zn含量在20~40 cm深度范围内随深度的增加而降低,40~60 cm深度范围内含量变化不大;Pb含量随深度的增加而减少。紫穗槐吸收尾矿土中Pb的能力最强,其次是Zn。紫穗槐根茎间对5种重金属的转运系数顺序为Cd>Zn>Pb>Cu>Cr,紫穗槐对Zn,Cd和Pb具有超转运能力。紫穗槐根对5种重金属的富集系数顺序为Cr>Zn>Cd>Cu>Pb,紫穗槐茎对5种重金属的富集系数顺序为Cr>Cd>Zn>Pb>Cu,紫穗槐根富集Cu和Cr重金属能力高于茎,富集Zn,Cd和Pb的能力低于茎,紫穗槐根对Cr具有超富集能力,茎对Cd和Cr具有超富集能力。紫穗槐修复尾矿土重金属纵向迁移主要来源于雨水淋滤作用、土壤吸附作用以及植物富集和转运作用,Cu迁移受雨水淋滤作用最大,Cd和Zn迁移受植物富集和转运作用最大,Pb迁移受土壤吸附作用最大,植物富集作用对Cr迁移的影响较高。研究结果对重金属污染尾矿库的植物修复具有参考价值。
By the model experimental device of phytoremediation tailings pond,stratified samples were taken of tailings soil at different depths in Amorpha Fruticosa rhizosphere,and the heavy metals Cu,Zn,Pb,Cd and Cr were detected.Analysis of heavy metal content at different depths,and the longitudinal migration law is analyzed.The analysis results show that:The contents of Zn,Cu,Cr and Pb in the tailings soil at different depths in the Amorpha Fruticosa rhizosphere were significantly higher than contents of Cd,among them,Cd content is the lowest,Zn content is the highest.With the increase of depth,Cr content decreased first and then increased.The content of Zn decreases with the increase of depth in the range of 20-40cm depth,and the content changes little in the range of 40-60cm depth.Pb content decreases with the increase of depth.The results showed that the ability of Pb enrichment was strongest of Amorpha Fruticosa in tailings soil,the second is Zn.The sequence of transfer coefficients of five heavy metals between roots and stems of Amorpha Fruticosa:Cd>Zn>Pb>Cu>Cr,and the supertransport capacity of Zn,Cd and Pb was obtained.The sequence of enrichment coefficients of five heavy metals by roots of Amorpha Fruticosa:Cr>Zn>Cd>Cu>Pb,The sequence of enrichment coefficients of heavy metals in the stems of Amorpha Fruticosa:Cr>Cd>Zn>Pb>Cu,the enrichment capacity of Cu and Cr heavy metals in root was higher than that in stem,while that in Zn,Cd and Pb was lower than that in stem,the root of Amorpha Fruticosa had superenrichment of Cr,and the stem had superenrichment of Cd and Cr.The vertical migration of heavy metals in the tailings of remediation of Amorpha Fruticosa was mainly caused by rainwater leaching,soil adsorption,plant enrichment and translocation.Cu migration is most influenced by rainwater leaching.The migration of Cd and Zn was most influenced by plant enrichment and transport.Pb migration was affected most by soil adsorption and least by rainwater leaching.The effect of plant enrichment on Cr migration was highe
出处
《环境保护与循环经济》
2020年第10期18-23,28,共7页
environmental protection and circular economy
基金
辽宁省自然科学基金项目(20180550192)
辽宁省科技计划项目(2019JH8/10300107)
辽宁省百千万人才资助项目(辽百千万立项〔2015〕33号)。
关键词
尾矿土
重金属
迁移
分布
富集
转运
tailings soil
heavy metals
migration
distribution
enrichment
transshipment
