Sources and ecological assessment of heavy metal contamination in the surface sediment in Honghai Bay

Abstract

The sources and ecological environment of heavy metal contamination in the surface sediment of the Honghai Bay were studied, and the contents of seven heavy metals in sediment samples from 20 sampling stations were analysed. Principal Component Analysis (PCA) showed that the contribution rates of the first and second principal component was 60.41% and 16.48%, respectively. The study showed that the major sources of heavy metal contamination were industrial wastewater and municipal wastewater. Combined with the results of correlation analysis between heavy metals and TOC, it was found that Cu, Pb, Zn, Cr and As had a certain degree of homology. The contribution rate of each pollutant variable calculated by PCA method was used to determine the marine sediment pollution index (MSPI) to evaluate the contamination level of heavy metal, and the potential adverse effects of heavy metal contamination on the ecological environment were evaluated by the mean sediment guideline quotient (SQG-Q). The results showed that the sediment conditions were average (MSPI: 40.30-57.92), and the potential adverse biological effects had reached a moderate level (SQG-Q: 0.10-0.21). Heavy metal contamination level of the study area was moderate.