Pollution assessment of heavy metals in the sediment of Jiulong River Estuary
九龙江河口沉积物重金属污染评价

By the Index of Geoaccumulation and the Potential Ecological Risk Index, a pollution assessment of seven heavy metals (Hg, Pb, Cr, Zn, Cu, Cd, and As) was made of the sediment in Jiulong River Estuary. The results of pollution assessment by Index of Geoaccumulation revealed Zn and Cr in this area belonged to none pollutants while Cu, Pb, Hg, and As in most stations were non or light pollutants. However, Cd in most stations was assessed as light or moderate pollutant. The assessment result of ecological risk revealed this area belonged to moderate potential ecological risk. The order of ecological risk was as the following, Cd>Hg >As>Pb>Cu >Cr>Zn. Principal component analysis was applied to estimate the possible sources of heavy metal pollution in this area. Results showed that degradation of organic matter and industrial wastewater were the main sources of heavy metal contamination, but the former was more important than the latter.