Source Apportionment and Risk Assessment of Heavy Metals (Cd, Cu, Ni, Pb, Zn, and Mn) in Surface Sediments from the Dragon Lake, Bengbu, China

Heavy metal concentrations in surface sediments of the Dragon Lake were studied based on the field investigation, sampling, indoor test and statistical analysis. Pollution risk was assessed using geoaccumulation index (I-geo), potential ecological risk index (PERI) and sediment quality guidelines (SQGs). The enrichment level of heavy metals in surface sediments decreased in the order of Cd>Zn>Cu>Ni>Pb>Mn. I-geo and PERI indicated Cd had the highest biological risk among the six heavy metals. The concentrations of Cd, Ni and Zn were between threshold effect level (TEL) and probable effect level (PEL), suggesting adverse biological effect occasionally occurred. Comparing the north and south of Dragon lake, the north part should be given more attention due to the higher heavy metal concentrations. The metals (Cd, Zn, Cu, Ni, and Pb) were attributed to anthropogenic sources, including agriculture, industrial emissions and traffic pollution, whereas Mn was mainly from natural sources. The results can provide reference for water quality management of Dragon Lake.

Automated summary

The study found high concentrations of heavy metals in the surface sediments of Dragon Lake, with Cd posing the highest biological risk. The north part of the lake showed higher pollution levels and should be given more attention. Heavy metals were mainly attributed to anthropogenic sources.