【摘要】 为探究湖北省阳新县复垦工矿废弃地土壤重金属污染状况及其潜在生态风险,对研究区采集的69个复垦工矿废弃地表层土壤样品中As、Cd、Cr、Cu、Hg、Ni、Pb和Zn 8种重金属元素的含量进行了测定,在此基础上分别采用内梅罗综合污染指数法和潜在生态风险指数法对复垦土壤中重金属污染程度和潜在生态风险进行了评价。结果表明:研究区复垦土壤中重金属元素Cd、Cu、Hg、Pb和Zn的含量均值高于湖北省土壤元素背景值,存在一定程度的富集,部分复垦土壤中重金属元素As、Cd、Cu和Ni的含量超过《土壤环境质量农用地土壤污染风险管控标准(试行)》(GB 15618—2018)中的土壤污染风险筛选值,超标率分别为8.7%、4.3%、10.1%和1.4%;复垦土壤中无清洁级别,预警、轻度污染、中度污染和重度污染土壤分别占1.48%、69.57%、18.84%和10.14%,各类型复垦土壤中重金属污染程度依次为金属矿采选废弃地>其他工矿废弃地>砂石场废弃地>煤矿采选废弃地,复垦土壤中各重金属单因子污染指数依次为Cd>Cu>Hg>Pb>Zn>Ni>As>Cr;复垦土壤中重金属元素As、Cr、Cu、Ni、Pb和Zn的单项潜在生态风险均处于低生态风险级别,而Cd和Hg最高分别达到较高和极高生态风险级别,复垦土壤重金属综合生态风险中,低生态风险、中等生态风险和高生态风险级别的土壤分别占66.67%、30.43%和2.90%,无极高生态风险级别的土壤。总体而言,研究区复垦土壤中重金属元素Cd和Cu的污染较突出,但考虑到毒性响应,复垦土壤中重金属Hg和Cd的污染更应引起警惕。更多还原

【Abstract】 To explore the heavy metal pollution and potential ecological risk of soil from reclaimed industrial and mining wasteland in Yangxin County,Hubei Province,this paper collects 69 surface soil samples from reclaimed wasteland in the study area and measures the contents of 8 heavy metals(As,Cd,Cr,Cu,Hg,Ni,Pb and Zn) and applies The Nemerow comprehensive pollution index method and the potential ecological risk index method to the heavy metal pollution and potential ecological risk assessment respectively.Results show that there is certain enrichment and pollution of heavy metals in the reclaimed soil;the contents of Cd,Cu,Hg,Pb and Zn in the reclaimed soil are higher than the background values of Hubei province,and the contents of As,Cd,Cu and Ni in some reclaimed soils exceed the screening values in Soil Environment Quality Risk Control Standard for Soil Contamination of Agriculture Land(GB 15618—2018) are 8.7%,4.3%,10.1% and 1.4% respectively.Results of heavy metal pollution assessment show that the reclaimed soil has no cleanliness level,and the early warning,mild pollution,moderate pollution and heavy pollution accounted for 1.48%,69.57%,18.84% and 10.14% respectively;the heavy metal pollution degree of each type of reclaimed soil is metal mining wasteland>other industrial and mining wasteland>abandoned gravel field>coal mining wasteland,and the single factor pollution index of each heavy metal is Cd>Cu>Hg>Pb>Zn>Ni>As>Cr.Results of potential ecological risk assessment indicate that the potential ecological risks of As,Cr,Cu,Ni,Pb and Zn are all at low ecological risk level,while the highest Cd and Hg levels reach relatively high and extremely high ecological risk levels respectively.Among the comprehensive potential ecological risk,low ecological risk,medium ecological risk and high ecological risk level account for 66.67%,30.43% and 2.90% respectively,and there was no extremely high ecological risk level.In general,Cd and Cu pollution was more prominent in reclaimed soils in the study area.With respect to the toxic response factor,Hg and Cd pollution should be more vigilant.更多还原