广西矿区土壤镉、铅污染状况研究

A study on contamination status of the Cd and Pb in the mines soil of GuangXi

对广西德保几个矿区尾矿土壤中镉和铅含量进行了测定,并初步探讨了土壤的污染状况。结果显示:土壤中镉和铅含量都超出了广西土壤环境质量标准的背景值(Cd 0.08 mg.kg-1,Pb 20 mg.kg-1),且镉含量明显超标,而铅在国家土壤环境质量标准下几乎无污染,但是已经达到广西土壤环境质量标准下的轻度污染;铜矿尾矿土壤中Cd的含量最高达2.16 mg.kg-1,已超过国家的三级标准,对生态开始产生影响;硫铁矿尾矿下游土壤中Pb的含量达83.53 mg.kg-1对生态基本无影响。土壤中Cd的含量随着pH值的升高而显著增加,而Pb的含量随着pH值的升高有所减少;土壤中Cd的含量不管就环境质量标准来说,还是单项污染指数,都属于严重污染级别,应减轻对生态环境的危害。因此应该引起相关部门的重视,及时采取措施控制污染源或者减轻污染程度。

In this article, the Cd and Pb contents of soil were determined and their contaminations were studied in several miners tailings ofGuangxi Debao. The results showed that the Cd and Pb contents in soil had all surpassed the background value of soil environment quality standard of Guangxi in concentration （Cd 0.08 mg·kg^-1 and Pb 20 mg·kg^-1）. Moreover, the Cd content was obvious exceeding. Pb had no pollution according to the soil environment quality standard of China, but it had already achieved mild pollution according to the standard of GuangXi. The Cd content of soil in copper mine tailing arrived to 2.16 mg·kg^-1 and exceeded the tertius standard of our country and it had began to affect the environment. The Pb content in lower reaches soil of the sulphurous iron ore tailing was 83.53 mg·kg^-1 and had no impact on the environment. The Cd content in soil increased significantly with pH increasing, while Pb content was decreased with pH increasing. The Cd content in soil arrived to serious pollution level as far as the environmental quality standards and individual pollution index were concerned. It should mitigate the harm to the ecological environment. There fore the correlated departments should emphasize the soil contamination by Cd and Pb in miners tailings, and adopt promptly some measures to control the pollution source and reduce the pollution degree.