Spatial Distribution Characteristics of Urban Topsoil Heavy Metals

By using R software and the geo-statistical methods,a model was established for analyzing the spatial distribution features of eight heavy metals in urban topsoil and the main impact factors.The results showed that the experimental variogram models of the As,Cd,Cr,Cu,Hg,Ni,Pb and Zn in the topsoil fitted well.All the heavy metals,except Cu and Hg,showed obvious spatial variation,the accumulation of heavy metals was mainly caused by human activities in the industrial,traffic,living areas and the fertilizers and pesticides,and there was a potential risk of mixed noxious contamination of heavy metals.