Unravelling biogeochemical drivers of methylmercury production in an Arctic fen soil and a bog soil
Arctic tundra soils store a globally significant amount of mercury (Hg), which could be transformed to the neurotoxic methylmercury (MeHg) upon warming and thus poses serious threats to the Arctic ecosystem. However, our knowledge of the biogeochemical drivers of MeHg production is limited in these...
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Online Access: | http://www.osti.gov/servlets/purl/1855690 https://www.osti.gov/biblio/1855690 https://doi.org/10.1016/j.envpol.2022.118878 |
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ftosti:oai:osti.gov:1855690 2023-07-30T04:01:16+02:00 Unravelling biogeochemical drivers of methylmercury production in an Arctic fen soil and a bog soil Zhang, Lijie Philben, Michael J. Taş, Neslihan Johs, Alexander Yang, Ziming Wullschleger, Stan D. Graham, David E. Pierce, Eric M. Gu, Baohua 2023-01-24 application/pdf http://www.osti.gov/servlets/purl/1855690 https://www.osti.gov/biblio/1855690 https://doi.org/10.1016/j.envpol.2022.118878 unknown http://www.osti.gov/servlets/purl/1855690 https://www.osti.gov/biblio/1855690 https://doi.org/10.1016/j.envpol.2022.118878 doi:10.1016/j.envpol.2022.118878 54 ENVIRONMENTAL SCIENCES 2023 ftosti https://doi.org/10.1016/j.envpol.2022.118878 2023-07-11T10:11:12Z Arctic tundra soils store a globally significant amount of mercury (Hg), which could be transformed to the neurotoxic methylmercury (MeHg) upon warming and thus poses serious threats to the Arctic ecosystem. However, our knowledge of the biogeochemical drivers of MeHg production is limited in these soils. Using substrate addition (acetate and sulfate) and selective microbial inhibition approaches, we investigated the geochemical drivers and dominant microbial methylators in 60-day microcosm incubations with two tundra soils: a circumneutral fen soil and an acidic bog soil, collected near Nome, Alaska, United States. Results showed that increasing acetate concentration had negligible influences on MeHg production in both soils. However, inhibition of sulfate-reducing bacteria (SRB) completely stalled MeHg production in the fen soil in the first 15 days, whereas addition of sulfate in the low-sulfate bog soil increased MeHg production by 5-fold, suggesting prominent roles of SRB in Hg(II) methylation. Without the addition of sulfate in the bog soil or when sulfate was depleted in the fen soil (after 15 days), both SRB and methanogens contributed to MeHg production. Analysis of microbial community composition confirmed the presence of several phyla known to harbor microorganisms associated with Hg(II) methylation in the soils. Lastly, the observations suggest that SRB and methanogens were mainly responsible for Hg(II) methylation in these tundra soils, although their relative contributions depended on the availability of sulfate and possibly syntrophic metabolisms between SRB and methanogens. Other/Unknown Material Arctic Nome Tundra Alaska SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Arctic Environmental Pollution 299 118878 |
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Open Polar |
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SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) |
op_collection_id |
ftosti |
language |
unknown |
topic |
54 ENVIRONMENTAL SCIENCES |
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54 ENVIRONMENTAL SCIENCES Zhang, Lijie Philben, Michael J. Taş, Neslihan Johs, Alexander Yang, Ziming Wullschleger, Stan D. Graham, David E. Pierce, Eric M. Gu, Baohua Unravelling biogeochemical drivers of methylmercury production in an Arctic fen soil and a bog soil |
topic_facet |
54 ENVIRONMENTAL SCIENCES |
description |
Arctic tundra soils store a globally significant amount of mercury (Hg), which could be transformed to the neurotoxic methylmercury (MeHg) upon warming and thus poses serious threats to the Arctic ecosystem. However, our knowledge of the biogeochemical drivers of MeHg production is limited in these soils. Using substrate addition (acetate and sulfate) and selective microbial inhibition approaches, we investigated the geochemical drivers and dominant microbial methylators in 60-day microcosm incubations with two tundra soils: a circumneutral fen soil and an acidic bog soil, collected near Nome, Alaska, United States. Results showed that increasing acetate concentration had negligible influences on MeHg production in both soils. However, inhibition of sulfate-reducing bacteria (SRB) completely stalled MeHg production in the fen soil in the first 15 days, whereas addition of sulfate in the low-sulfate bog soil increased MeHg production by 5-fold, suggesting prominent roles of SRB in Hg(II) methylation. Without the addition of sulfate in the bog soil or when sulfate was depleted in the fen soil (after 15 days), both SRB and methanogens contributed to MeHg production. Analysis of microbial community composition confirmed the presence of several phyla known to harbor microorganisms associated with Hg(II) methylation in the soils. Lastly, the observations suggest that SRB and methanogens were mainly responsible for Hg(II) methylation in these tundra soils, although their relative contributions depended on the availability of sulfate and possibly syntrophic metabolisms between SRB and methanogens. |
author |
Zhang, Lijie Philben, Michael J. Taş, Neslihan Johs, Alexander Yang, Ziming Wullschleger, Stan D. Graham, David E. Pierce, Eric M. Gu, Baohua |
author_facet |
Zhang, Lijie Philben, Michael J. Taş, Neslihan Johs, Alexander Yang, Ziming Wullschleger, Stan D. Graham, David E. Pierce, Eric M. Gu, Baohua |
author_sort |
Zhang, Lijie |
title |
Unravelling biogeochemical drivers of methylmercury production in an Arctic fen soil and a bog soil |
title_short |
Unravelling biogeochemical drivers of methylmercury production in an Arctic fen soil and a bog soil |
title_full |
Unravelling biogeochemical drivers of methylmercury production in an Arctic fen soil and a bog soil |
title_fullStr |
Unravelling biogeochemical drivers of methylmercury production in an Arctic fen soil and a bog soil |
title_full_unstemmed |
Unravelling biogeochemical drivers of methylmercury production in an Arctic fen soil and a bog soil |
title_sort |
unravelling biogeochemical drivers of methylmercury production in an arctic fen soil and a bog soil |
publishDate |
2023 |
url |
http://www.osti.gov/servlets/purl/1855690 https://www.osti.gov/biblio/1855690 https://doi.org/10.1016/j.envpol.2022.118878 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Nome Tundra Alaska |
genre_facet |
Arctic Nome Tundra Alaska |
op_relation |
http://www.osti.gov/servlets/purl/1855690 https://www.osti.gov/biblio/1855690 https://doi.org/10.1016/j.envpol.2022.118878 doi:10.1016/j.envpol.2022.118878 |
op_doi |
https://doi.org/10.1016/j.envpol.2022.118878 |
container_title |
Environmental Pollution |
container_volume |
299 |
container_start_page |
118878 |
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1772812011344756736 |