Winter Ecosystem Respiration and Sources of CO2 From the High Arctic Tundra of Svalbard: Response to a Deeper Snow Experiment
Currently, there is a lack of understanding on how the magnitude and sources of carbon (C) emissions from High Arctic tundra are impacted by changing snow cover duration and depth during winter. Here we investigated this issue in a graminoid tundra snow fence experiment on shale-derived gelisols in...
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ftcdlib:oai:escholarship.org/ark:/13030/qt56j3g416 2023-05-15T14:55:34+02:00 Winter Ecosystem Respiration and Sources of CO2 From the High Arctic Tundra of Svalbard: Response to a Deeper Snow Experiment Lupascu, M Czimczik, CI Welker, MC Ziolkowski, LA Cooper, EJ Welker, JM 2627 - 2642 2018-08-01 application/pdf https://escholarship.org/uc/item/56j3g416 unknown eScholarship, University of California qt56j3g416 https://escholarship.org/uc/item/56j3g416 public Journal of Geophysical Research: Biogeosciences, vol 123, iss 8 Geophysics article 2018 ftcdlib 2021-06-28T17:06:59Z Currently, there is a lack of understanding on how the magnitude and sources of carbon (C) emissions from High Arctic tundra are impacted by changing snow cover duration and depth during winter. Here we investigated this issue in a graminoid tundra snow fence experiment on shale-derived gelisols in Svalbard from the end of the growing season and throughout the winter. To characterize emissions, we measured ecosystem respiration (Reco) along with its radiocarbon (14C) content. We assessed the composition of soil organic matter (SOM) by measuring its bulk-C and nitrogen (N), 14C content, and n-alkane composition. Our findings reveal that greater snow depth increased soil temperatures and winter Reco (25mg C m−2 d−1 under deeper snow compared to 13mg C m−2 d−1 in ambient conditions). At the end of the growing season, Reco was dominated by plant respiration and microbial decomposition of C fixed within the past 60years (Δ14C=62±8‰). During winter, emissions were significantly older (Δ14C=−64±14‰), and likely sourced from microorganisms decomposing aged SOM formed during the Holocene mixed with biotic or abiotic mineralization of the carbonaceous, fossil parent material. Our findings imply that snow cover duration and depth is a key control on soil temperatures and thus the magnitude of Reco in winter. We also show that in shallow Arctic soils, mineralization of carbonaceous parent materials can contribute significant proportions of fossil C to Reco. Therefore, permafrost-C inventories informing C emission projections must carefully distinguish between more vulnerable SOM from recently fixed biomass and more recalcitrant ancient sedimentary C sources. Article in Journal/Newspaper Arctic permafrost Svalbard Tundra University of California: eScholarship Arctic Svalbard |
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University of California: eScholarship |
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language |
unknown |
topic |
Geophysics |
spellingShingle |
Geophysics Lupascu, M Czimczik, CI Welker, MC Ziolkowski, LA Cooper, EJ Welker, JM Winter Ecosystem Respiration and Sources of CO2 From the High Arctic Tundra of Svalbard: Response to a Deeper Snow Experiment |
topic_facet |
Geophysics |
description |
Currently, there is a lack of understanding on how the magnitude and sources of carbon (C) emissions from High Arctic tundra are impacted by changing snow cover duration and depth during winter. Here we investigated this issue in a graminoid tundra snow fence experiment on shale-derived gelisols in Svalbard from the end of the growing season and throughout the winter. To characterize emissions, we measured ecosystem respiration (Reco) along with its radiocarbon (14C) content. We assessed the composition of soil organic matter (SOM) by measuring its bulk-C and nitrogen (N), 14C content, and n-alkane composition. Our findings reveal that greater snow depth increased soil temperatures and winter Reco (25mg C m−2 d−1 under deeper snow compared to 13mg C m−2 d−1 in ambient conditions). At the end of the growing season, Reco was dominated by plant respiration and microbial decomposition of C fixed within the past 60years (Δ14C=62±8‰). During winter, emissions were significantly older (Δ14C=−64±14‰), and likely sourced from microorganisms decomposing aged SOM formed during the Holocene mixed with biotic or abiotic mineralization of the carbonaceous, fossil parent material. Our findings imply that snow cover duration and depth is a key control on soil temperatures and thus the magnitude of Reco in winter. We also show that in shallow Arctic soils, mineralization of carbonaceous parent materials can contribute significant proportions of fossil C to Reco. Therefore, permafrost-C inventories informing C emission projections must carefully distinguish between more vulnerable SOM from recently fixed biomass and more recalcitrant ancient sedimentary C sources. |
format |
Article in Journal/Newspaper |
author |
Lupascu, M Czimczik, CI Welker, MC Ziolkowski, LA Cooper, EJ Welker, JM |
author_facet |
Lupascu, M Czimczik, CI Welker, MC Ziolkowski, LA Cooper, EJ Welker, JM |
author_sort |
Lupascu, M |
title |
Winter Ecosystem Respiration and Sources of CO2 From the High Arctic Tundra of Svalbard: Response to a Deeper Snow Experiment |
title_short |
Winter Ecosystem Respiration and Sources of CO2 From the High Arctic Tundra of Svalbard: Response to a Deeper Snow Experiment |
title_full |
Winter Ecosystem Respiration and Sources of CO2 From the High Arctic Tundra of Svalbard: Response to a Deeper Snow Experiment |
title_fullStr |
Winter Ecosystem Respiration and Sources of CO2 From the High Arctic Tundra of Svalbard: Response to a Deeper Snow Experiment |
title_full_unstemmed |
Winter Ecosystem Respiration and Sources of CO2 From the High Arctic Tundra of Svalbard: Response to a Deeper Snow Experiment |
title_sort |
winter ecosystem respiration and sources of co2 from the high arctic tundra of svalbard: response to a deeper snow experiment |
publisher |
eScholarship, University of California |
publishDate |
2018 |
url |
https://escholarship.org/uc/item/56j3g416 |
op_coverage |
2627 - 2642 |
geographic |
Arctic Svalbard |
geographic_facet |
Arctic Svalbard |
genre |
Arctic permafrost Svalbard Tundra |
genre_facet |
Arctic permafrost Svalbard Tundra |
op_source |
Journal of Geophysical Research: Biogeosciences, vol 123, iss 8 |
op_relation |
qt56j3g416 https://escholarship.org/uc/item/56j3g416 |
op_rights |
public |
_version_ |
1766327597067665408 |