Pollution assessment and source analysis of soil heavy metals in a concentrated distribution area of agricultural in Chongqing
The problem of soil heavy metal pollution is becoming increasingly serious.Identifying the sources of soil heavy metal pollution has important guiding roles for pollution prevention and risk management control.A concentrated distribution area of agricultural soils in Chongqing was selected to study the pollution characteristics and sources of heavy metals in soils by multiple methods including geo-accumulation index,pollution load index,correlation analysis,principal component analysis and positive matrix factorization.The results showed that the average concentrations of heavy metals(Cd,Hg,As,Pb,Cr,Cu,Zn and Ni)in the surface soil all exceeded the soil background value in Chongqing,showing different levels of enrichment.The highest cumulative element in surface soil was Hg,followed by As and Cd,and their average concentrations were 54.70,3.03,1.50 times of the soil background values of the Chongqing.The statistical results of the geo-accumulation index indicated that Hg and As were pollutants in the study area with a high pollution level.The evaluation results of the pollution load index method showed that the study area was slightly polluted as a whole,and the comprehensive pollution load index(Pzone)of the study area was 1.76.The results of positive matrix factorization showed that the accumulation of As and Pb in the soil of the study area were mainly caused by industrial activities and traffic emissions,and Cr,Cu,Zn and Ni in the soils were mainly from natural geological background,and Cd in the soils was mainly caused by agricultural production activities,and Hg in the soils was mainly caused by mining of mercury ore.
万方数据
维普
