摘要
以天津港及其周围的矿产品堆场为研究区域,选取6个受污染的堆场土壤作为样本,用王水-HF-H2O2作为消解液,经微波消解后采用等离子体发射光谱仪(ICP-AES)测定土壤中Cu、Pb、Cd、Ni、Zn、As、Cr的质量比,并用Hakanson生态风险指数法对土壤污染程度进行潜在生态风险评价。结果表明:土壤中的Cd、As污染严重,污染水平超过三级土壤水平;土壤的潜在生态风险指数RI处于极高风险程度,Cd和As在潜在生态风险指数中的贡献比例超过95%,Ni、Pb、Cu、Cr和Zn等元素的影响可以忽略不计;堆场中20 cm深度土壤的潜在生态风险指数RI大于60 cm深度的土壤,地表以下60 cm深度的土壤也受到了一定程度的污染。为防止天津港矿产品堆场内的重金属元素向周围继续迁移、扩散,应减少高镉高砷矿石的进口,在堆场的土壤污染监测中应重点关注Cd、As,防止土壤酸化。
This article intends to provide our evaluation of the heavy metal pollution in the soil in-situ of the mineral products in the stor- age yards of Tianjin Port Harbor. For our research purpose, we have collected investigation samples from six highly selected points of the storage yard and a neighbor spot. As an analysis device, we have chosen to use the ICP- AES technique to determine the content and concentration of the samples, under study, including such metals as Cu, Pb, Cd, Ni, Zn, As and Cr, after the microwave pretreatment with aqua regia, HF and H202. While doing our analysis, we have introduced Hakanson＇s ecological risk index into our work in hoping to evaluate the potential ecological risk of the minerals which are like- ly to lead to the contaminated soil. The results of our investigation and analysis can be shown as follows： （1） The soil samples chosen prove to be heavily polluted and contaminated by the hazardous cona-pounds containing Cd and As, whose concentration turns to be far be- yondthe specified scope that Grade III of the soil pollution standard has given; （2） The ecological risk index （RI） reveals that the area under investigationJ^hould be classified into heavily contaminated and environmentally severe damaged one, whose contaminated concentra- tion of Cd and As is as high as to 95 % of the RI value, though the contamination induced by Ni, Pb, Cu, Cr and Zn seem to be negligi- ble; （3） In spite of the fact that the RI value of the soil sample col- lected in the depth of 60 cm is smaller than that in depth of 20 cm, strong evidence can still be found that the soil in the deep layer was still gradually polluted. In order to prevent further exacerbation and extension of the pollution by the heavy metal contamination from the mineral storage yards around Tianjin Port Harbor, it is necessary to reduce and restrict the import of minerals containing high concentra- tion of Cd and As. At the same time, it is also necessary to enhance the soil survey of the mineral storage yards and stress the analysis of the soil＇s damage and pollution hazards with the focused determina- tion of the content of Cd and As to reduce the soil＇s acidification.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2013年第4期146-150,共5页
Journal of Safety and Environment
基金
国家质检总局科技计划项目(2011IK046)
关键词
环境学
重金属污染
矿产品堆场
潜在生态风险评价
environmentalology
heavy metal pollution
mineral stor- age yards
potential ecological risk evaluation
