Stoichiometry and temperature sensitivity of methanogenesis and CO 2 production from saturated polygonal tundra in Barrow, Alaska
Arctic permafrost ecosystems store ~50% of global belowground carbon (C) that is vulnerable to increased microbial degradation with warmer active layer temperatures and thawing of the near surface permafrost. We used anoxic laboratory incubations to estimate anaerobic CO2 production and methanogenes...
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ftosti:oai:osti.gov:1185515 2023-07-30T04:02:07+02:00 Stoichiometry and temperature sensitivity of methanogenesis and CO 2 production from saturated polygonal tundra in Barrow, Alaska Roy Chowdhury, Taniya Herndon, Elizabeth M. Phelps, Tommy J. Elias, Dwayne A. Gu, Baohua Liang, Liyuan Wullschleger, Stan D. Graham, David E. 2023-06-26 application/pdf http://www.osti.gov/servlets/purl/1185515 https://www.osti.gov/biblio/1185515 https://doi.org/10.1111/gcb.12762 unknown http://www.osti.gov/servlets/purl/1185515 https://www.osti.gov/biblio/1185515 https://doi.org/10.1111/gcb.12762 doi:10.1111/gcb.12762 54 ENVIRONMENTAL SCIENCES 58 GEOSCIENCES 37 INORGANIC ORGANIC PHYSICAL AND ANALYTICAL CHEMISTRY 2023 ftosti https://doi.org/10.1111/gcb.12762 2023-07-11T08:59:43Z Arctic permafrost ecosystems store ~50% of global belowground carbon (C) that is vulnerable to increased microbial degradation with warmer active layer temperatures and thawing of the near surface permafrost. We used anoxic laboratory incubations to estimate anaerobic CO2 production and methanogenesis in active layer (organic and mineral soil horizons) and permafrost samples from center, ridge and trough positions of water-saturated low-centered polygon in Barrow Environmental Observatory, Barrow AK, USA. Methane (CH4) and CO2 production rates and concentrations were determined at 2, +4, or +8 C for 60 day incubation period. Temporal dynamics of CO2 production and methanogenesis at 2 C showed evidence of fundamentally different mechanisms of substrate limitation and inhibited microbial growth at soil water freezing points compared to warmer temperatures. Nonlinear regression better modeled the initial rates and estimates of Q10 values for CO2 that showed higher sensitivity in the organic-rich soils of polygon center and trough than the relatively drier ridge soils. Methanogenesis generally exhibited a lag phase in the mineral soils that was significantly longer at 2 C in all horizons. Such discontinuity in CH4 production between 2 C and the elevated temperatures (+4 and +8 C) indicated the insufficient representation of methanogenesis on the basis of Q10 values estimated from both linear and nonlinear models. Production rates for both CH4 and CO2 were substantially higher in organic horizons (20% to 40% wt. C) at all temperatures relative to mineral horizons (<20% wt. C). Permafrost horizon (~12% wt. C) produced ~5-fold less CO2 than the active layer and negligible CH4. High concentrations of initial exchangeable Fe(II) and increasing accumulation rates signified the role of iron as terminal electron acceptors for anaerobic C degradation in the mineral horizons. Other/Unknown Material Arctic Barrow permafrost Tundra Alaska SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Arctic Global Change Biology 21 2 722 737 |
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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 58 GEOSCIENCES 37 INORGANIC ORGANIC PHYSICAL AND ANALYTICAL CHEMISTRY |
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54 ENVIRONMENTAL SCIENCES 58 GEOSCIENCES 37 INORGANIC ORGANIC PHYSICAL AND ANALYTICAL CHEMISTRY Roy Chowdhury, Taniya Herndon, Elizabeth M. Phelps, Tommy J. Elias, Dwayne A. Gu, Baohua Liang, Liyuan Wullschleger, Stan D. Graham, David E. Stoichiometry and temperature sensitivity of methanogenesis and CO 2 production from saturated polygonal tundra in Barrow, Alaska |
topic_facet |
54 ENVIRONMENTAL SCIENCES 58 GEOSCIENCES 37 INORGANIC ORGANIC PHYSICAL AND ANALYTICAL CHEMISTRY |
description |
Arctic permafrost ecosystems store ~50% of global belowground carbon (C) that is vulnerable to increased microbial degradation with warmer active layer temperatures and thawing of the near surface permafrost. We used anoxic laboratory incubations to estimate anaerobic CO2 production and methanogenesis in active layer (organic and mineral soil horizons) and permafrost samples from center, ridge and trough positions of water-saturated low-centered polygon in Barrow Environmental Observatory, Barrow AK, USA. Methane (CH4) and CO2 production rates and concentrations were determined at 2, +4, or +8 C for 60 day incubation period. Temporal dynamics of CO2 production and methanogenesis at 2 C showed evidence of fundamentally different mechanisms of substrate limitation and inhibited microbial growth at soil water freezing points compared to warmer temperatures. Nonlinear regression better modeled the initial rates and estimates of Q10 values for CO2 that showed higher sensitivity in the organic-rich soils of polygon center and trough than the relatively drier ridge soils. Methanogenesis generally exhibited a lag phase in the mineral soils that was significantly longer at 2 C in all horizons. Such discontinuity in CH4 production between 2 C and the elevated temperatures (+4 and +8 C) indicated the insufficient representation of methanogenesis on the basis of Q10 values estimated from both linear and nonlinear models. Production rates for both CH4 and CO2 were substantially higher in organic horizons (20% to 40% wt. C) at all temperatures relative to mineral horizons (<20% wt. C). Permafrost horizon (~12% wt. C) produced ~5-fold less CO2 than the active layer and negligible CH4. High concentrations of initial exchangeable Fe(II) and increasing accumulation rates signified the role of iron as terminal electron acceptors for anaerobic C degradation in the mineral horizons. |
author |
Roy Chowdhury, Taniya Herndon, Elizabeth M. Phelps, Tommy J. Elias, Dwayne A. Gu, Baohua Liang, Liyuan Wullschleger, Stan D. Graham, David E. |
author_facet |
Roy Chowdhury, Taniya Herndon, Elizabeth M. Phelps, Tommy J. Elias, Dwayne A. Gu, Baohua Liang, Liyuan Wullschleger, Stan D. Graham, David E. |
author_sort |
Roy Chowdhury, Taniya |
title |
Stoichiometry and temperature sensitivity of methanogenesis and CO 2 production from saturated polygonal tundra in Barrow, Alaska |
title_short |
Stoichiometry and temperature sensitivity of methanogenesis and CO 2 production from saturated polygonal tundra in Barrow, Alaska |
title_full |
Stoichiometry and temperature sensitivity of methanogenesis and CO 2 production from saturated polygonal tundra in Barrow, Alaska |
title_fullStr |
Stoichiometry and temperature sensitivity of methanogenesis and CO 2 production from saturated polygonal tundra in Barrow, Alaska |
title_full_unstemmed |
Stoichiometry and temperature sensitivity of methanogenesis and CO 2 production from saturated polygonal tundra in Barrow, Alaska |
title_sort |
stoichiometry and temperature sensitivity of methanogenesis and co 2 production from saturated polygonal tundra in barrow, alaska |
publishDate |
2023 |
url |
http://www.osti.gov/servlets/purl/1185515 https://www.osti.gov/biblio/1185515 https://doi.org/10.1111/gcb.12762 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Barrow permafrost Tundra Alaska |
genre_facet |
Arctic Barrow permafrost Tundra Alaska |
op_relation |
http://www.osti.gov/servlets/purl/1185515 https://www.osti.gov/biblio/1185515 https://doi.org/10.1111/gcb.12762 doi:10.1111/gcb.12762 |
op_doi |
https://doi.org/10.1111/gcb.12762 |
container_title |
Global Change Biology |
container_volume |
21 |
container_issue |
2 |
container_start_page |
722 |
op_container_end_page |
737 |
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1772812837399298048 |