Characterization and source analysis of topsoil heavy metal pollution in Nanjing,Yangtze River Delta Region
This study examined the pollution characteristics of heavy metals(Cd,Cr,Cu,Mn,Ni,Pb,and Zn)in the shallow soils of Nanjing's urban core,a typical industrial city in the Yangtze River Delta.The sources of heavy metals in the soil were interpreted using kriging and multivariate statistical analysis methods.The results showed that Cd,Cr,Cu,Mn,Ni,Pb,and Zn were all enriched in the soil of the main urban area of Nanjing,with average contents of 0.24,76.9,36.45,707.22,35.48,32.65,and 99.75mg/kg,respectively.From the perspective of spatial distribution characteristics,it was found that the contents of heavy metal elements Zn,Cu,Cd,and Pb in the soil of Nanjing were higher in industrial areas.High values of Zn,Cu,and Pb were observed in the old urban areas.The contents of Ni and Cr were generally higher in industrial areas and lower in the old urban areas.The distribution trend of Mn was relatively gentle and significantly different from the other six heavy metal elements.Based on the results of principal component analysis and cluster analysis,it could be determined that Zn,Cu,Cd,and Pb in the soil of Nanjing were mainly affected by industrial and transportation activities.Ni and Cr were primarily influenced by industrial activities,while Mn was mainly from natural sources.Industrial and transportation activities were identified as important causes of heavy metal pollution in the soil of industrial cities in the Yangtze River Delta region.They were also crucial directions for the prevention and control of soil heavy metal pollution in the Yangtze River Delta region.
urban topsoilsoil heavy metalspatial distributionsources analysisYangtze River DeltaNanjing
NETL
NSTL
万方数据
