摘要
对湘南某钨矿区土壤的污染现状和当地植物修复能力进行调查,采用BCR连续提取法和改进后的逐步提取法,分别分析土壤和植物中As、Cd、Cr、Pb、Zn的形态,评价钨矿区土壤中As、Cd、Cr、Pb、Zn的生态风险。结果表明,尾矿库、垅下河区域Cd、As、Zn为主要污染,选厂和废石坝区As、Cd、Pb为主要污染。根据植物重金属形态分布、富集系数、转移系数,得出尾矿库、垅下河区域适合小蓬草和一年蓬原位修复,选厂和废石坝区域适合一年蓬和五节芒原位修复。
This paper is intended to make an analysis of the distributive features of As,Cd,Cr,Pb and Zn in the soil and the botanic feautres of a tungsten in the southern part of Hunan as the research goal,correspondingly,by using the BCR continuous extraction method. What we want to achieve is to improve step by step the extraction features through an evaluation of the ecological risk likely to be brought about by the above said metallic pollutants in the soil of tungsten ore zone via the enrichment coefficient method and the potential ecological risk index analysis.The result of our research shows that the existence of Cd in the soil as the contaminant acid,which are soluble and oxidizable,whereas the contaminants of As,Cr,Pb exist in the soil as reducible and residual. In comparison,Zn is mainly present as a kind of acid being soluble and reducible. All this has made the evaluation of the heavy metal enrichment and joint serious contamination correspondingly due to the heavy contamination of As and Cd in the soil,though the pollution of Cr,Pb and Zn is slight or pollution free. Thus,generally speaking,the contamination of Cd is serous and therefore can result in the greatest hazard. Thus,according to the analysis results of the heavy metal contaminant distribution,the enrichment coefficient and transfer coefficient of plants have enabled us to find that conyza canadens tends to have the greatest capability of beneficial potential to remove the pollutants of Cd and Zn. What is more,the erigeron annuus tends also to have a stronger beneficial capability for As,Cr and Pb than that of Conyza canadensis. Apart from it,erigeron annuus also presents an ability to transport As,Cr,Cd,Pb and Zn,with the transfer coefficient of Cr,much greater than that of conyza canadensis and miscanthus floridulus. Furthermore,miscanthus floridulus tends to bring about strong burden of transportation of Cd and Cr,especially,with the transfer coefficient of Cd higher than that of the others. Since conyza canadensis enjoys greatest transfer coeffi
作者
阳雨平
杨田杰
陈国国
YANG Yu-ping;YANG Tian-jie;CHEN Guo-guo(School of Resources and Safety Engineering,Central South University,Changsha 410083,China)
出处
《安全与环境学报》
CAS
CSCD
北大核心
2019年第5期1752-1760,共9页
Journal of Safety and Environment
关键词
环境工程学
重金属污染
植物修复
重金属形态
生态风险
environmental engineering
heavy metal pollution
phytoremediation
heavy metal morphology
ecological risk
