某金矿尾矿库土壤重金属污染特征及来源分析

Characteristics of soil pollution by heavy metal and ananlysis of pollution source of tailings pond of a certain gold mine

尾矿中含有的重金属通过介质向环境缓慢释放,重金属进入土壤后,会对周围土壤、生态环境造成影响,危害人类身体健康和安全。本文以某金矿尾矿库为研究对象,对尾矿库流域内土壤重金属进行取样调查,确定尾矿库及周边土壤重金属污染现状,分析重金属来源及污染特征。对尾矿库及周边的土壤进行pH、氰化物、锑、砷、镉、铜、铅、锌、汞等元素含量测试,采用单项污染指数与内梅罗指数法进行重金属污染程度分析与评价;同时运用主成分分析法,探究尾矿库及周边区域土壤重金属形成原因和污染特征。研究结果表明:尾矿库流域内地表土样处于重污染状态,污染区主要集中在尾矿库东北侧,污染范围较大;氰化物、锑、镉、铜、铅、锌存在着不同程度的相关性,表明研究区内存在这6种元素不同程度的复合污染或这些元素具有同源性,重金属污染主要来源为矿石开采和工业活动等人为来源;土壤中砷的吸附、迁移与土壤pH值关系密切。调查和分析尾矿库土壤污染情况,查明尾矿库污染形成原因和污染特征,对尾矿库的综合治理具有重要意义。

The heavy metals contained in the tailings are slowly released to the environment through the medium.When the heavy metals enter the soil environment,they will cause impacts on the surrounding soil and ecological environment and harm human health and safety.Taking a gold mine tailings pond as the research object,the soil heavy metal in the tailing pond basin was sampled to determine the current situation of heavy metal pollution in the tailing pond and surrounding soil,and the source and pollution characteristics of heavy metals were analyzed.Soil samples were taken from the tailing pond and its surroundings to test the contents of pH,cyanide,Sb,As,Cd,Cu,Pb,Zn,Hg sampling detection,and the pollution degree of heavy metals was analyzed and evaluated by single pollution index and nemero index method.At the same time,the principal component analysis was conducted to explore the formation causes and pollution characteristics of heavy metals in the soil of the tailings pond and surrounding areas.The results show that the topsoil samples in the inland area of tailings pond are heavily polluted,and the polluted area is mainly in the northeast side of the tailings pond,and the pollution range is large.The correlation of cyanide,Sb,Cd,Cu,Pb and Zn in different degrees indicates that these 6 elements have compound pollution or homology in different degrees in the study area.The main sources of heavy metal pollution are artificial sources such as ore mining and industrial activities.The adsorption and migration of As in soil are closely related to the pH value of soil.It is of great significance to investigate and analyze the soil pollution of tailings pond and find out the causes and characteristics of the pollution of tailings pond.