Characterization and source apportionment of heavy metal contamination in surface sediments from the Zhuyukou Waterway, Pingtan Island, Southeast China

Understanding the spatial distribution and sources of heavy metal contamination in coastal sediments is crucial for developing effective pollution prevention strategies and promoting sustainable regional economic development. This study systematically investigated the contamination characteristics and spatial distributions of eight heavy metals (V, Cr, Co, Ni, Cu, Zn, Cd, and Pb) in surface sediments from the Zhuyukou Waterway, Pingtan Island, Southeast China, and the sources of these heavy metals were identified through principal component analysis (PCA) combined with positive matrix factorization (PMF) modeling. The results reveal that the average concentrations of V, Cr, Co, Ni, Cu, Zn, Cd, and Pb are 95.41, 71.20, 13.59, 31.30, 30.26, 132.13, 0.22, and 30.92 mg·kg –1 respectively. Influenced by sediment granulometry and surrounding land-use characteristics, the spatial distribution patterns exhibit significant heterogeneity. The pollution assessment reveals that Cd exhibits moderate to high pollution levels across the study area, while V、Cr、Co、Ni、Cu、Zn、Pb present uncontaminated to moderately contaminated. Cd stands out as the predominant pollutant, which requires particular attention. Source apportionment through PMF modeling reveals that three major contributors are quantified, including natural weathering processes (47.3 %), industrial and transportation activities (31.3 %), and agricultural practices (21.4 %). To achieve sustainable coastal ecosystem management, it is imperative to establish systematic coordination among port construction, industrial planning, and marine environmental monitoring, while implementing science-based spatial planning for aquaculture operations.