Distribution pattern and potential ecological risk assessment of heavy metals in the sediments of Jiulong River estuary

An analysis and evaluation of the monitoring results on seven heavy metals in 18 sample points of Jiulong River estuary was conducted in May 2011. Heavy metal pollution was assessed based on the geo-accumulation index and the potential ecological risk index. The result of geo-accumulation index indicates the pollution degree of the seven heavy metals is Cd > Zn > Pb > Cu > As > Hg > Cr; and the result of potential ecological risk index indicates that the ecological hazard degree of the seven heavy metals is: Cd > Hg > As > Pb > Cu > Zn > Cr. The potential ecological risk of heavy metals in the surface sediments is of intermediate level. Results of the two assessment methods both show that the pollution degree of Cd is the severest, which indicates that the heavy metal pollutants at Jiulong river estuary mainly come from the drainage basin.