Contamination zoning for soil heavy metal at county scale in developed area

Soil heavy metal contamination is a hot issue of social concern, and its regionalization is the basis of remediation. The integrated approaches of geo-statistical, cluster analysis, and principal component analysis were applied to conduct the soil heavy metals contamination zoning of Kunshan at county scale. The results of zoning included two grades, five soil contamination zones and ten soil contamination sub-zones according to cluster analysis of soil contamination and contamination-forming environment. The integrated approach of the two-step cluster analysis not only revealed the spatial differences of heavy metals contamination distribution in this area, but also further reflected the key factors which caused the contamination from outside of each unit. The research can provide some references to the heavy metal contamination control and remediation.