Heavy metal contamination in farm soils at Licheng Plainarea and its risk assessment based on GIS

The pollution on the farm land in Licheng plain area and its potential ecological risk caused by heavy metal contamination were studied based on the spatial interpolation.The result showed that the single highest pollution index of 8 heavy metals was Hg.The average combined pollution index of heavy metals on the farm land was 0.897,at the warning level.However,the over-all soil condition was acceptable.Among the 8 heavy metals,Hg had the greatest index of potential ecological hazard,i.e.,47.496,which was at the medium hazard level.The indices for the other 7 elements ranged from 0.362 to 12.058, at the light hazard level.The combined index of potential pollution risk of heavy metals on the farmland was 27.742 to 127.344,averaging 68.129,which is considered a low hazard.A soil quality classification for the area based on the pollution risk index by the GIS technology was presented.