浙西南典型耕地土壤重金属空间分布及污染评价OA北大核心CSTPCD

[Objective]The heavy metal contamination of farmland in one town of Liandu District,was comprehensively mapped through soil sample collection and analysis,providing a scientific basis for subsequent comprehensive soil safety management and comprehensive pollution management.[Method]The principal component analysis(PCA),single-factor pollution index method(Pi),the Nemero index method(Pc),the land accumulation index method(Igeo),the potential ecological risk index method(IR)and ecological risk early warning index(IER)were used to analyze pollution assessment,and source analysis of heavy metal pollution in the study area.[Result]The exceedance rates of Cd and Pb(risk screening value)were 60.71%and 39.29%,respectively,but both were lower than the risk control value of soil pollution on agricultural land.The average value Piof Cd was 1.31,indicating a slightly polluted level,while Pivalue of the other heavy metals was less than 1,indicating in the clean.Pc value was 1.10,indicating a slightly polluted level.The Igeo value of Cd and Pb was 1.74 and 0.79,indicating in moderate pollution and no pollution-moderate pollution respectively,the rest of the heavy metals was in the clean.The average potential ecological hazard coefficient Eir of five heavy metals was less than 40,indicating a slight ecological risk.The average value of IR was 48.87,indicating a slight ecological risk.IER reached the slight early warning.Hg and Cr were influenced by both human and natural factors,while Cd,Pb and As were mainly caused human activities such as mining pollution and livestock manure application.[Conclusion]The soil in the study area is generally slightly polluted.Cd and Pb are the most important ecological elements in agricultural soils,and subsequent treatment and dynamic detection should be increased to ensure the safety of agricultural products.[Ch,4 fig.6 tab.37 ref.]