Distribution and pollution assessment of heavy metals and petroleum hydrocarbon in surface sediments from Chenglingji Port

Concentration of 4 heavy metals (Cu, Pb,Zn, Cd) and petroleum hydrocarbon in the surface sediments collected from Chenglingji, Dongting Lake, were quantitatively analyzed. Distribution characteristics and possible sources of the heavy metals and petroleum hydrocarbon were discussed. Methods of single-factor index and geoaccumulation index were adopted to evaluate the potential ecological risks of heavy metal. The results showed that Cd was seriously polluted and in a strong ecological risk level; Cu, Pb and Zn pollution was mild in Chenglingji Port, Dongting Lake. Petroleum hydrocarbon content of nearshore sediment was low exclude of area near Chenglingji Port, which significantly exceeded the standard value. And the content of petroleum hydrocarbon decreased with the distance far away from the harbor.