Geochemical baseline establishment and pollution assessment of heavy metals in the largest coastal lagoon (Pinqing Lagoon) in China mainland

• Published in: Marine pollution bulletin 2022-04, Vol.177, p.113459-113459, Article 113459
• Main Authors: Xian, Hanbiao, Dong, Xuhui, Wang, Yu, Li, Yan, Xing, Jinhuai, Jeppesen, Erik
• Format: Article
• Language: English
• Subjects: Anthropogenic factors; Cadmium; Catchment area; Clean energy; Coastal lagoons; Coastal management; Coastal zone; Coastal zones; Copper; Cores; Environmental assessment; Environmental management; Environmental risk; Geochemical baseline; Geochemistry; Heavy metal; Heavy metals; Human influences; Lagoons; Metals; Pollution control; Risk levels; Sediment; Sediment pollution; Sediments
• ISSN: 0025-326X; 1879-3363
• DOI: 10.1016/j.marpolbul.2022.113459

Establishing geochemical baselines and assessment of heavy metal pollution in lagoon sediments are critical for providing guidance to coastal zone environmental management. We analyzed heavy metals in high-resolution sediment cores from Pinqing Lagoon in South China, and defined the baselines of common pollution elements with a significant anthropogenic contribution. With these baselines, a spatiotemporal pollution assessment revealed Cu and Cd as the predominant pollution metals in both core and surface sediments, although the ecological risk level in the interior lagoon remained low during the past ~170 years. Surface sediment pollution status indicate a significant spatial difference. The findings from this typical coastal lagoon evidence a strong self-clean capacity attributable to the frequent water-mass-energy exchange between the lagoon and the sea. Furthermore, despite the significant impact by the sea, the geochemical baselines are close to the catchment soil backgrounds that can be defined using a paleolimnological approach. [Display omitted] •Baseline of heavy metal pollution defined for Pinqing Lagoon•Reliable baseline information obtained based on paleolimnological analysis•Low ecological risk observed in the lagoon since the 1850s•Significant spatial variance recorded in heavy metal pollution•Strong sea-land hydrological exchange helps pollution control in coastal lagoons.