Pollution characteristics and source analysis of heavy metals in surface sediments of Luoyuan Bay, Fujian

The concentrations of eight heavy metals, V, Cr, Co, Ni, Cu, Zn, Cd, and Pb, were analyzed to explore the environmental pollution characteristics, ecological risk levels, and sources of heavy metals in the surface sediments of Luoyuan Bay in Fujian Province. The results indicated that the mean concentrations of V, Cr, Co, Ni, Cu, Zn, Cd, and Pb were 110.44, 97.76, 17.35, 41.99, 36.78, 137.26, 0.09, and 35.81 mg⋅kg^-1, respectively. The mean concentrations of Cr, Cu, and Zn exceeded the first category of the marine sediment quality standards, indicating a moderate regional comprehensive potential ecological hazard level. Due to variable hydrodynamic conditions, high concentrations of heavy metals were observed in the north and low concentrations were observed in the south, with high values generally recorded near steel plants and shipyard docks. Correlation and principal component analyses revealed that the V, Al, Co, Ni, and Pb originated from the weathering and erosion of rocks, and industrial wastewater discharge. Contrastingly, Cu, Zn, Cr, and Cd were mainly associated with the transportation and repair of ships, and marine aquaculture activities.