Wang, Baolin
- Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
Research article2020Peer reviewedOpen access
Hu, Haiyan; Wang, Baolin; Bravo, Andrea G.; Bjorn, Erik; Skyllberg, Ulf; Amouroux, David; Tessier, Emmanuel; Zopfi, Jakob; Feng, Xinbin; Bishop, Kevin; Nilsson, Mats B.; Bertilsson, Stefan
Peatlands are globally important ecosystems where inorganic mercury is converted to bioaccumulating and highly toxic methylmercury, resulting in high risks of methylmercury exposure in adjacent aquatic ecosystems. Although biological mercury methylation has been known for decades, there is still a lack of knowledge about the organisms involved in mercury methylation and the drivers controlling their methylating capacity. In order to investigate the metabolisms responsible for mercury methylation and methylmercury degradation as well as the controls of both processes, we studied a chronosequence of boreal peatlands covering fundamentally different biogeochemical conditions. Potential mercury methylation rates decreased with peatland age, being up to 53 times higher in the youngest peatland compared to the oldest. Methylation in young mires was driven by sulfate reduction, while methanogenic and syntrophic metabolisms became more important in older systems. Demethylation rates were also highest in young wetlands, with a gradual shift from biotic to abiotic methylmercury degradation along the chronosequence. Our findings reveal how metabolic shifts drive mercury methylation and its ratio to demethylation as peatlands age.
Mercury; Methylation; Demethylation; Peatland; Chronosequence
Journal of Hazardous Materials
2020, Volume: 387, article number: 121967Publisher: ELSEVIER
Non-toxic environment
SDG6 Clean water and sanitation
Environmental Sciences
DOI: https://doi.org/10.1016/j.jhazmat.2019.121967
https://res.slu.se/id/publ/104966