Spatial Distribution and Risk Assessment of Hg in Topsoil at JPG Gold Mine, China

摘要

The objectives of this study were to characterize the spatial distribution of Hg in topsoil at Jia-Pi-Gou(JPG),a centuried gold mine area,and to evaluate the Hg pollution risks.A total of 28 soil samples were collected by a stratified random sampling technique.Descriptive statistics and ANN were used to analyze the data.The results show that the mean value of Hg in the soil was 0.203mg·kg-1,higher than Chinese Soil Environmental Quality Standard's soil quality standard.In the ANN figure,the high concentrations of Hg are found in three main spots,two of which are gold mine and one of which is gold mine tailing and the three spots are the center of high concentration.The geo-accumulation index assessment shows that all farmland topsoil in JPG is contaminated by Hg,while different sampling sites are contaminated to different levels,among all 53.57％ are beyond heavily contaminated.