Evaluation of potential relationships between benthic community structure and toxic metals in Laizhou Bay

- Paired sediment metals and macrobenthos were investigated in Laizhou Bay.
- Sediment metals analyzed were not responsible for the benthic community alteration.
- Riverine dominated factors may account for benthic community alteration.
- Sediment impairment were mainly distributed the northern central portion of Laizhou Bay.
- This is the first weight of evidence alike integrated sediment quality assessment in this area.

The objective of the present study was to examine the relationships between benthic community structure and toxic metals using bivariate/multivariate techniques at 17 sediment locations in Laizhou Bay, North China. Sediment chemical data were evaluated against geochemical background values and sediment quality guidelines, which identified Cu and As as contaminants of concern with a moderate potential for adverse effects. Benthic community data were subjected to non-metric multidimensional scaling, which generated four groups of stations. Spearman rank correlation was then employed to explore the relationships between the major axes of heavy metals and benthic community structure. However, weak and insignificant correlations were found between these axes, indicating that contaminants of concern may not be the primary explanatory factors. Polychaeta were abundant in southern Laizhou Bay, serving as a warning regarding the health status of the ecosystem. Integrated sediment quality assessment showed sediments from northern central locations were impaired, displaying less diverse benthos and higher metal contamination.