Temperature and moisture effects on greenhouse gas emissions from deep active-layer boreal soils
Rapid climatic changes, rising air temperatures, and increased fires are expected to drive permafrost degradation and alter soil carbon (C) cycling in many high-latitude ecosystems. How these soils will respond to changes in their temperature, moisture, and overlying vegetation is uncertain but crit...
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Online Access: | http://www.osti.gov/servlets/purl/1339816 https://www.osti.gov/biblio/1339816 https://doi.org/10.5194/bg-13-6669-2016 |
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ftosti:oai:osti.gov:1339816 2023-07-30T04:06:17+02:00 Temperature and moisture effects on greenhouse gas emissions from deep active-layer boreal soils Bond-Lamberty, Ben Smith, A. Peyton Bailey, Vanessa L. 2023-06-26 application/pdf http://www.osti.gov/servlets/purl/1339816 https://www.osti.gov/biblio/1339816 https://doi.org/10.5194/bg-13-6669-2016 unknown http://www.osti.gov/servlets/purl/1339816 https://www.osti.gov/biblio/1339816 https://doi.org/10.5194/bg-13-6669-2016 doi:10.5194/bg-13-6669-2016 54 ENVIRONMENTAL SCIENCES 2023 ftosti https://doi.org/10.5194/bg-13-6669-2016 2023-07-11T09:16:51Z Rapid climatic changes, rising air temperatures, and increased fires are expected to drive permafrost degradation and alter soil carbon (C) cycling in many high-latitude ecosystems. How these soils will respond to changes in their temperature, moisture, and overlying vegetation is uncertain but critical to understand given the large soil C stocks in these regions. We used a laboratory experiment to examine how temperature and moisture control CO 2 and CH 4 emissions from mineral soils sampled from the bottom of the annual active layer, i.e., directly above permafrost, in an Alaskan boreal forest. Gas emissions from 30 cores, subjected to two temperatures and either field moisture conditions or experimental drought, were tracked over a 100-day incubation; we also measured a variety of physical and chemical characteristics of the cores. Gravimetric water content was 0.31 ± 0.12 (unitless) at the beginning of the incubation; cores at field moisture were unchanged at the end, but drought cores had declined to 0.06 ± 0.04. Daily CO 2 fluxes were positively correlated with incubation chamber temperature, core water content, and percent soil nitrogen. They also had a temperature sensitivity ( Q 10 ) of 1.3 and 1.9 for the field moisture and drought treatments, respectively. Daily CH 4 emissions were most strongly correlated with percent nitrogen, but neither temperature nor water content was a significant first-order predictor of CH 4 fluxes. The cumulative production of C from CO 2 was over 6 orders of magnitude higher than that from CH 4 cumulative CO 2 was correlated with incubation temperature and moisture treatment, with drought cores producing 52–73 % lower C. Cumulative CH 4 production was unaffected by any treatment. These results suggest that deep active-layer soils may be sensitive to changes in soil moisture under aerobic conditions, a critical factor as discontinuous permafrost thaws in interior Alaska. Furthermore, deep but unfrozen high-latitude soils have been shown to be strongly affected by long-term ... Other/Unknown Material permafrost Alaska SciTec Connect (Office of Scientific and Technical Information - OSTI, U.S. Department of Energy) Biogeosciences 13 24 6669 6681 |
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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 Bond-Lamberty, Ben Smith, A. Peyton Bailey, Vanessa L. Temperature and moisture effects on greenhouse gas emissions from deep active-layer boreal soils |
topic_facet |
54 ENVIRONMENTAL SCIENCES |
description |
Rapid climatic changes, rising air temperatures, and increased fires are expected to drive permafrost degradation and alter soil carbon (C) cycling in many high-latitude ecosystems. How these soils will respond to changes in their temperature, moisture, and overlying vegetation is uncertain but critical to understand given the large soil C stocks in these regions. We used a laboratory experiment to examine how temperature and moisture control CO 2 and CH 4 emissions from mineral soils sampled from the bottom of the annual active layer, i.e., directly above permafrost, in an Alaskan boreal forest. Gas emissions from 30 cores, subjected to two temperatures and either field moisture conditions or experimental drought, were tracked over a 100-day incubation; we also measured a variety of physical and chemical characteristics of the cores. Gravimetric water content was 0.31 ± 0.12 (unitless) at the beginning of the incubation; cores at field moisture were unchanged at the end, but drought cores had declined to 0.06 ± 0.04. Daily CO 2 fluxes were positively correlated with incubation chamber temperature, core water content, and percent soil nitrogen. They also had a temperature sensitivity ( Q 10 ) of 1.3 and 1.9 for the field moisture and drought treatments, respectively. Daily CH 4 emissions were most strongly correlated with percent nitrogen, but neither temperature nor water content was a significant first-order predictor of CH 4 fluxes. The cumulative production of C from CO 2 was over 6 orders of magnitude higher than that from CH 4 cumulative CO 2 was correlated with incubation temperature and moisture treatment, with drought cores producing 52–73 % lower C. Cumulative CH 4 production was unaffected by any treatment. These results suggest that deep active-layer soils may be sensitive to changes in soil moisture under aerobic conditions, a critical factor as discontinuous permafrost thaws in interior Alaska. Furthermore, deep but unfrozen high-latitude soils have been shown to be strongly affected by long-term ... |
author |
Bond-Lamberty, Ben Smith, A. Peyton Bailey, Vanessa L. |
author_facet |
Bond-Lamberty, Ben Smith, A. Peyton Bailey, Vanessa L. |
author_sort |
Bond-Lamberty, Ben |
title |
Temperature and moisture effects on greenhouse gas emissions from deep active-layer boreal soils |
title_short |
Temperature and moisture effects on greenhouse gas emissions from deep active-layer boreal soils |
title_full |
Temperature and moisture effects on greenhouse gas emissions from deep active-layer boreal soils |
title_fullStr |
Temperature and moisture effects on greenhouse gas emissions from deep active-layer boreal soils |
title_full_unstemmed |
Temperature and moisture effects on greenhouse gas emissions from deep active-layer boreal soils |
title_sort |
temperature and moisture effects on greenhouse gas emissions from deep active-layer boreal soils |
publishDate |
2023 |
url |
http://www.osti.gov/servlets/purl/1339816 https://www.osti.gov/biblio/1339816 https://doi.org/10.5194/bg-13-6669-2016 |
genre |
permafrost Alaska |
genre_facet |
permafrost Alaska |
op_relation |
http://www.osti.gov/servlets/purl/1339816 https://www.osti.gov/biblio/1339816 https://doi.org/10.5194/bg-13-6669-2016 doi:10.5194/bg-13-6669-2016 |
op_doi |
https://doi.org/10.5194/bg-13-6669-2016 |
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Biogeosciences |
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13 |
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24 |
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6669 |
op_container_end_page |
6681 |
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