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The mercury (Hg) cycle in estuaries has been globally discussed, although Holocene deposition in mangrove sediments remains unknown. Herein, a sediment core from a mangrove system in southeastern Brazil was C-dated to evaluate millennial Hg deposition. The highest Hg concentrations (1010-2540 ng g) in surface sediments were explained by emissions from a chlor-alkali industry (1964 CE). However, Hg levels were also high in pre-industrial periods, associated to fine grain-size and algal organic deposition. Less anomalous Hg concentrations in bottom sediments indicate Holocene ages (~1940-3324 cal yr BP), potentially associated to Serra do Mar mountains weathering. This study reveals the capacity of mangrove to retain Hg over millennial time scales, acting as significant and long-term Hg sinks. Therefore, the use of Hg as an Anthropocene marker must be considered cautiously in coastal systems that act as Hg sinks in times when environmental changes were not caused by human activities.
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http://dx.doi.org/10.1016/j.marpolbul.2021.113031 | DOI Listing |
Mar Pollut Bull
September 2025
School of Environmental Science and Engineering, Xiamen University of Technology, Xiamen, 361021, China; Xiamen Key Laboratory of Membrane Research and Application, Xiamen, 361024, China. Electronic address:
With the rapid economic development of coastal cities, the discharge of significant amounts of heavy metal pollutants has posed a severe threat to mangrove forests. However, the potential sources of these metals and the health risks they pose remain poorly understood. This study analyzed 14 heavy metals in mangrove and river sediments of Zhangjiang Estuary, southeastern China.
View Article and Find Full Text PDFMar Environ Res
September 2025
Center for the Study of Sediments, College of Hydrosphere Science, National Kaohsiung University of Science and Technology, Kaohsiung City 81157, Taiwan; Department of Marine Environmental Engineering, National Kaohsiung University of Science and Technology, Kaohsiung City, 81157, Taiwan; Internatio
Plankton drives coastal biogeochemical processes and pollutant transfer in the aquatic food chain. However, the dearth of studies hinders a holistic understanding of pollutant behavior, distribution, and potential climate impacts. This study concurrently analyzed metals in seawater, suspended particulates, phytoplankton, and zooplankton, quantified using an inductively coupled plasma mass spectrometer (ICP-MS).
View Article and Find Full Text PDFMar Environ Res
September 2025
State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, 510301, China; Sanya Institute of Ocean Eco-Environmental Engineering, Sanya, 572000, China. Electronic address:
There has been a significant reduction in natural mangrove wetlands as a result of human activities and climate change, particularly in densely populated and industrially developed regions. This situation underscores the necessity for research into the environmental behavior of trace metals in mangrove plants and their potential for phytoremediation. In this study, the environmental behaviors of seven trace metals were investigated in three wetlands in the Pearl River Delta, one of the most highly urbanized watersheds in China.
View Article and Find Full Text PDFJ Hazard Mater
August 2025
Research Centre for the Oceans and Human Health, City University of Hong Kong Shenzhen Research Institute, Shenzhen 518057, China; School of Energy and Environment and State Key Laboratory of Marine Pollution, City University of Hong Kong, Kowloon, Hong Kong, China. Electronic address: wx.wang@cityu
Blue carbon ecosystems act as critical sinks for microplastics (MPs), yet field-based evidence of their biogeochemical consequences remains scarce. In this study, we conducted in situ exposures of estuarine mangroves to environmentally relevant concentrations of polypropylene (PP) and polylactic acid (PLA) MPs for 30 and 100 days. Metagenomic analyses revealed stable microbial community composition across treatments.
View Article and Find Full Text PDFEnviron Monit Assess
September 2025
National Institute of Oceanography, Panaji, Goa, India.
The study investigated bioaccumulation of metals in edible bivalves and crustaceans in the Mandovi Estuary, assessing the potential toxicity to biota and human consumers. Additionally, it examined the phytoremediation potential of mangrove species in the Mandovi Estuary. The concentration of essential (Fe, Mn, Zn, Cu, Co and Ni) and toxic (Hg) metals exceeded the upper crustal average, indicating their anthropogenic contribution to estuarine environment.
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