Distribution Characteristics and Potential Ecological Risk Assessment of Asenic and Mercury in Vegetable Soils of Changchun Suburb

The vegetable soils in Changchun suburb were investigated to study the concentration, distribution characteristics and potential ecological risk assessment of As,Hg.The results indicated that the concentrations of As and Hg were lower than the China Soil Environment Quality Standard level II,,that is,the concentrations of As and Hg in soil were not detrimental to plant growth and thus suitable for vegetable planting,however they both generally exceeded the Changchun baseline values. Distribution characteristics showed that coal burning in industries was the main source of As and Hg,and the highest contents of As,Hg were both located in the northeast and southwest part of Changchun suburb.The correlation analysis showed As and Hg had the same source,and there was no significant correlation between the contents of As and Hg and pH due to the influence of anthropogenic activities,but the contents of As and Hg were positively related with organic matter. In general,vegetable farm soil possessed slight potential ecological risk,but some areas reached strong potential ecological risk. Since As exposed low potential risk while Hg possessed high potential ecological risk,more attention needs to be paid to control the input of Hg.