表层土壤重金属元素污染特征及潜在生态风险评价:以山东省东部为例

Characteristics of Heavy Metal Pollution Surface Soil and Potential Ecological Risk Assessment: Example from the Eastern Shandong Province

针对当前土壤污染研究中存在的问题,提出了一种模糊识别土壤重金属元素污染评价的方法。并对瑞典学者(Hakan-son)提出的潜在生态危害指数法进行了改进,用以评价重金属元素潜在生态风险。采用建立的方法对山东省东部地区土壤重金属元素潜在生态风险进行了评价,结果表明:本区土壤重金属元素污染程度为Hg>Cd>Cu>Pb>Zn>Cr>As;而重金属元素潜在生态风险大小则依次为Hg、Cd、As、Pb、Cu、Cr、Zn。总体来看,山东省东部地区存在一定程度的重金属元素污染,其潜在生态风险为强和很强的土壤占13.75%,这种综合危害特征主要受Hg和Cd元素制约,主要分布在莱州—招远—烟台和牟平—乳山金矿集中区以及人口密集的城镇地带,且已对农作物安全产生影响。认为地质背景和人类活动(采金污染、工业生产、城市人口密集生活等)的共同作用,是造成局部环境中潜在生态风险较高的主要原因。

This paper presents a method that is able to vaguely evaluate heavy metal pollution in soil to solve the occurring soil pollution problems.The authors redefined the potential ecological risk index which was proposed by Hakanson,a Sweden researcher,in order to evaluate the potential ecological risk of heavy metals.The presented method was adapted to evaluate the potential ecological risk of heavy metals in soil of eastern Shandong Province.The results demonstrate that the degree of heavy metal pollution in soil in the study area is as the decreasing order of Hg＆gt;Cd＆gt;Cu＆gt;Pb＆gt;Zn＆gt;Cr＆gt;As.Particularly,the potential ecological risk of heavy metals is identified as the order of Hg,Cd,As,Pb,Cu,Cr,Zn.A certain degree of heavy metal pollution occurred in the eastern Shandong Province,leading to the 13.75% soil with the high potential ecological risk caused by heavy metal pollution.The integrated features of damage were constrained by Hg and Cd,distributed in the area of Laizhou-Zhaoyuan-Yantai and Mouping-Rushan where gold mines are concentrated and towns with intensive population.And safety of the crop production has already been affected.It is considered that the geological background and human activities（including pollution from gold exploration,industry,the city with a dense population） are the main factors resulting in the high potential ecological risk in the local environment.