Anaerobic respiration pathways and response to increased substrate availability of Arctic wetland soils
The availability of labile carbon (C) compounds in Arctic wetland soils is expected to increase due to thawing permafrost and increased fermentation as a result of decomposition of organic matter with warming. How microbial communities respond to this change will affect the balance of CO 2 and CH 4...
Published in: | Environmental Science: Processes & Impacts |
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Online Access: | http://www.osti.gov/servlets/purl/1661241 https://www.osti.gov/biblio/1661241 https://doi.org/10.1039/d0em00124d |
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ftosti:oai:osti.gov:1661241 2023-07-30T04:01:21+02:00 Anaerobic respiration pathways and response to increased substrate availability of Arctic wetland soils Philben, Michael J. Zhang, Lijie Yang, Ziming Taş, Neslihan Wullschleger, Stan D. Graham, David E. Gu, Baohua 2021-08-30 application/pdf http://www.osti.gov/servlets/purl/1661241 https://www.osti.gov/biblio/1661241 https://doi.org/10.1039/d0em00124d unknown http://www.osti.gov/servlets/purl/1661241 https://www.osti.gov/biblio/1661241 https://doi.org/10.1039/d0em00124d doi:10.1039/d0em00124d 54 ENVIRONMENTAL SCIENCES 2021 ftosti https://doi.org/10.1039/d0em00124d 2023-07-11T09:46:55Z The availability of labile carbon (C) compounds in Arctic wetland soils is expected to increase due to thawing permafrost and increased fermentation as a result of decomposition of organic matter with warming. How microbial communities respond to this change will affect the balance of CO 2 and CH 4 emitted during anaerobic organic matter decomposition, and ultimately the net radiative forcing of greenhouse gas emissions from these soils. While soil water content limits aerobic respiration, the factors controlling methanogenesis and anaerobic respiration are poorly defined in suboxic Arctic soils. In this study, we conducted incubation experiments on two tundra soils from field sites on the Seward Peninsula, Alaska, with contrasting pH and geochemistry to determine the pathways of anaerobic microbial respiration and changes with increasing substrate availability upon warming. In incubation of soils from the circumneutral Teller site, the ratio of CO 2 to CH 4 dropped from 10 to <2 after 60 days, indicating rapid depletion of alternative terminal electron acceptors (TEAs). Addition of acetate stimulated production of CO 2 and CH 4 in a nearly 1:1 ratio, consistent with methanogenesis, and the composition of the microbial community shifted to favor clades capable of utilizing the added acetate such as the Fe(III)-reducing Geobacter and the methanogenic archaea Methanosarcina. In contrast, both CO 2 and CH 4 production declined with acetate addition during incubation of soils from the more acidic Council site, and fermentative microorganisms increased in abundance despite the high availability of fermentation products. These results demonstrate that the degree to which increasing substrate availability stimulates greenhouse gas production in tundra wetlands will vary widely depending on soil pH and geochemistry. Other/Unknown Material Arctic permafrost Seward Peninsula Tundra Alaska SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Arctic Environmental Science: Processes & Impacts 22 10 2070 2083 |
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SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) |
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54 ENVIRONMENTAL SCIENCES |
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54 ENVIRONMENTAL SCIENCES Philben, Michael J. Zhang, Lijie Yang, Ziming Taş, Neslihan Wullschleger, Stan D. Graham, David E. Gu, Baohua Anaerobic respiration pathways and response to increased substrate availability of Arctic wetland soils |
topic_facet |
54 ENVIRONMENTAL SCIENCES |
description |
The availability of labile carbon (C) compounds in Arctic wetland soils is expected to increase due to thawing permafrost and increased fermentation as a result of decomposition of organic matter with warming. How microbial communities respond to this change will affect the balance of CO 2 and CH 4 emitted during anaerobic organic matter decomposition, and ultimately the net radiative forcing of greenhouse gas emissions from these soils. While soil water content limits aerobic respiration, the factors controlling methanogenesis and anaerobic respiration are poorly defined in suboxic Arctic soils. In this study, we conducted incubation experiments on two tundra soils from field sites on the Seward Peninsula, Alaska, with contrasting pH and geochemistry to determine the pathways of anaerobic microbial respiration and changes with increasing substrate availability upon warming. In incubation of soils from the circumneutral Teller site, the ratio of CO 2 to CH 4 dropped from 10 to <2 after 60 days, indicating rapid depletion of alternative terminal electron acceptors (TEAs). Addition of acetate stimulated production of CO 2 and CH 4 in a nearly 1:1 ratio, consistent with methanogenesis, and the composition of the microbial community shifted to favor clades capable of utilizing the added acetate such as the Fe(III)-reducing Geobacter and the methanogenic archaea Methanosarcina. In contrast, both CO 2 and CH 4 production declined with acetate addition during incubation of soils from the more acidic Council site, and fermentative microorganisms increased in abundance despite the high availability of fermentation products. These results demonstrate that the degree to which increasing substrate availability stimulates greenhouse gas production in tundra wetlands will vary widely depending on soil pH and geochemistry. |
author |
Philben, Michael J. Zhang, Lijie Yang, Ziming Taş, Neslihan Wullschleger, Stan D. Graham, David E. Gu, Baohua |
author_facet |
Philben, Michael J. Zhang, Lijie Yang, Ziming Taş, Neslihan Wullschleger, Stan D. Graham, David E. Gu, Baohua |
author_sort |
Philben, Michael J. |
title |
Anaerobic respiration pathways and response to increased substrate availability of Arctic wetland soils |
title_short |
Anaerobic respiration pathways and response to increased substrate availability of Arctic wetland soils |
title_full |
Anaerobic respiration pathways and response to increased substrate availability of Arctic wetland soils |
title_fullStr |
Anaerobic respiration pathways and response to increased substrate availability of Arctic wetland soils |
title_full_unstemmed |
Anaerobic respiration pathways and response to increased substrate availability of Arctic wetland soils |
title_sort |
anaerobic respiration pathways and response to increased substrate availability of arctic wetland soils |
publishDate |
2021 |
url |
http://www.osti.gov/servlets/purl/1661241 https://www.osti.gov/biblio/1661241 https://doi.org/10.1039/d0em00124d |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic permafrost Seward Peninsula Tundra Alaska |
genre_facet |
Arctic permafrost Seward Peninsula Tundra Alaska |
op_relation |
http://www.osti.gov/servlets/purl/1661241 https://www.osti.gov/biblio/1661241 https://doi.org/10.1039/d0em00124d doi:10.1039/d0em00124d |
op_doi |
https://doi.org/10.1039/d0em00124d |
container_title |
Environmental Science: Processes & Impacts |
container_volume |
22 |
container_issue |
10 |
container_start_page |
2070 |
op_container_end_page |
2083 |
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1772812095095570432 |