Emerging environmental risks to the largest coastal lagoon (Pinqing Lagoon) on the Chinese mainland: Assessment through a water-sediment-ecological perspective

Yajing Wang; Xuhui Dong; Hanbiao Xian; Yupei Zhang; Yan Li; Yu Wang; Helen Bennion

doi:10.1016/j.marpolbul.2024.117498

Emerging environmental risks to the largest coastal lagoon (Pinqing Lagoon) on the Chinese mainland: Assessment through a water-sediment-ecological perspective

Mar Pollut Bull. 2024 Dec 30:212:117498. doi: 10.1016/j.marpolbul.2024.117498. Online ahead of print.

Authors

Yajing Wang¹, Xuhui Dong², Hanbiao Xian¹, Yupei Zhang³, Yan Li¹, Yu Wang⁴, Helen Bennion⁵

Affiliations

¹ School of Geography and Remote Sensing, Guangzhou University, Guangzhou 510006, China; Centre for Climate and Environmental Changes, Guangzhou University, Guangzhou 510006, China.
² School of Geography and Remote Sensing, Guangzhou University, Guangzhou 510006, China; Centre for Climate and Environmental Changes, Guangzhou University, Guangzhou 510006, China. Electronic address: xhdong@gzhu.edu.cn.
³ School of Geography and Remote Sensing, Guangzhou University, Guangzhou 510006, China.
⁴ Institute of Environmental Research at Greater Bay, Guangzhou University, Guangzhou 510006, China.
⁵ Department of Geography, University College London, Gower Street, London WC1E 6BT, UK.

PMID: 39740521
DOI: 10.1016/j.marpolbul.2024.117498

Abstract

Coastal lagoons are vital yet vulnerable marine ecosystems. This study analyzes a five-year dataset to evaluate changes in water quality and their impacts on biota in Pinqing Lagoon (PQL). Seasonal surveys conducted from 2019 to 2023 across 14 sites revealed significant variability in water and sediment quality parameters. During the wet summer season, water quality deteriorated significantly as nutrient levels peaked. In contrast, the dry winter season posed a high ecological risk from heavy metals (HMs), specifically Cu, Hg, and Cd, in sediments. Sediment core analysis indicates upward trends in HMs since the 1950s. Salinity and pH are the primary drivers shaping the benthic communities in transitional zones, while nutrients and HMs primarily affect organisms in the inner bay. Nutrient enrichment has exacerbated HM accumulation and ecological degradation, with tolerance to HMs emerging as a critical factor for benthic survival. This comprehensive assessment of PQL highlights the seasonal patterns of pollution in urban lagoons, providing valuable insights for future conservation efforts.

Keywords: Biodiversity; Coastal lagoon; Eutrophication; Heavy metal; Water quality.