Redistribution of soil organic matter by permafrost disturbance in the Canadian High Arctic
This is an accepted manuscript of a published article. With increased warming in the Arctic, permafrost thaw may induce localized physical disturbance of slopes. These disturbances, referred to as active layer detachments (ALDs), redistribute soil across the landscape, potentially releasing previous...
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Springer International Publishing
2016
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Online Access: | http://hdl.handle.net/1807/81096 https://doi.org/10.1007/s10533-016-0215-7 |
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ftunivtoronto:oai:localhost:1807/81096 2023-05-15T14:51:52+02:00 Redistribution of soil organic matter by permafrost disturbance in the Canadian High Arctic Grewer, David M. Lafrenière, Melissa J. Lamoureux, Scott F. Simpson, Myrna J. 2016-07 http://hdl.handle.net/1807/81096 https://doi.org/10.1007/s10533-016-0215-7 en_ca eng Springer International Publishing 0168-2563 http://hdl.handle.net/1807/81096 doi:10.1007/s10533-016-0215-7 Cape Bounty Soil organic matter characterization Active layer detachments Solvent extractable biomarkers Solid-state 13C nuclear magnetic resonance Article Post-Print 2016 ftunivtoronto https://doi.org/10.1007/s10533-016-0215-7 2020-06-17T12:08:53Z This is an accepted manuscript of a published article. With increased warming in the Arctic, permafrost thaw may induce localized physical disturbance of slopes. These disturbances, referred to as active layer detachments (ALDs), redistribute soil across the landscape, potentially releasing previously unavailable carbon (C). In 2007–2008, widespread ALD activity was reported at the Cape Bounty Arctic Watershed Observatory in Nunavut, Canada. Our study investigated organic matter (OM) composition in soil profiles from ALD-impacted and undisturbed areas. Solid-state 13C nuclear magnetic resonance (NMR) and solvent-extractable biomarkers were used to characterize soil OM. Throughout the disturbed upslope profile, where surface soils and vegetation had been removed, NMR revealed low O-alkyl C content and biomarker analysis revealed low concentrations of solvent-extractable compounds suggesting enhanced erosion of labile-rich OM by the ALD. In the disturbed downslope region, vegetation remained intact but displaced material from upslope produced lateral compression ridges at the surface. High O-alkyl content in the surface horizon was consistent with enrichment of carbohydrates and peptides, but low concentrations of labile biomarkers (i.e., sugars) suggested the presence of relatively unaltered labile-rich OM. Decreased O-alkyl content and biomarker concentrations below the surface contrasted with the undisturbed profile and may indicate the loss of well-established pre-ALD surface drainage with compression ridge formation. However, pre-ALD profile composition remains unknown and the observed decreases may result from nominal pre-ALD OM inputs. These results are the first to establish OM composition in ALD-impacted soil profiles, suggesting reallocation of permafrost-derived soil C to areas where degradation or erosion may contribute to increased C losses from disturbed Arctic soils. Other/Unknown Material Arctic Nunavut permafrost University of Toronto: Research Repository T-Space Arctic Nunavut Canada Cape Bounty ENVELOPE(-109.542,-109.542,74.863,74.863) Biogeochemistry 128 3 397 415 |
institution |
Open Polar |
collection |
University of Toronto: Research Repository T-Space |
op_collection_id |
ftunivtoronto |
language |
English |
topic |
Cape Bounty Soil organic matter characterization Active layer detachments Solvent extractable biomarkers Solid-state 13C nuclear magnetic resonance |
spellingShingle |
Cape Bounty Soil organic matter characterization Active layer detachments Solvent extractable biomarkers Solid-state 13C nuclear magnetic resonance Grewer, David M. Lafrenière, Melissa J. Lamoureux, Scott F. Simpson, Myrna J. Redistribution of soil organic matter by permafrost disturbance in the Canadian High Arctic |
topic_facet |
Cape Bounty Soil organic matter characterization Active layer detachments Solvent extractable biomarkers Solid-state 13C nuclear magnetic resonance |
description |
This is an accepted manuscript of a published article. With increased warming in the Arctic, permafrost thaw may induce localized physical disturbance of slopes. These disturbances, referred to as active layer detachments (ALDs), redistribute soil across the landscape, potentially releasing previously unavailable carbon (C). In 2007–2008, widespread ALD activity was reported at the Cape Bounty Arctic Watershed Observatory in Nunavut, Canada. Our study investigated organic matter (OM) composition in soil profiles from ALD-impacted and undisturbed areas. Solid-state 13C nuclear magnetic resonance (NMR) and solvent-extractable biomarkers were used to characterize soil OM. Throughout the disturbed upslope profile, where surface soils and vegetation had been removed, NMR revealed low O-alkyl C content and biomarker analysis revealed low concentrations of solvent-extractable compounds suggesting enhanced erosion of labile-rich OM by the ALD. In the disturbed downslope region, vegetation remained intact but displaced material from upslope produced lateral compression ridges at the surface. High O-alkyl content in the surface horizon was consistent with enrichment of carbohydrates and peptides, but low concentrations of labile biomarkers (i.e., sugars) suggested the presence of relatively unaltered labile-rich OM. Decreased O-alkyl content and biomarker concentrations below the surface contrasted with the undisturbed profile and may indicate the loss of well-established pre-ALD surface drainage with compression ridge formation. However, pre-ALD profile composition remains unknown and the observed decreases may result from nominal pre-ALD OM inputs. These results are the first to establish OM composition in ALD-impacted soil profiles, suggesting reallocation of permafrost-derived soil C to areas where degradation or erosion may contribute to increased C losses from disturbed Arctic soils. |
format |
Other/Unknown Material |
author |
Grewer, David M. Lafrenière, Melissa J. Lamoureux, Scott F. Simpson, Myrna J. |
author_facet |
Grewer, David M. Lafrenière, Melissa J. Lamoureux, Scott F. Simpson, Myrna J. |
author_sort |
Grewer, David M. |
title |
Redistribution of soil organic matter by permafrost disturbance in the Canadian High Arctic |
title_short |
Redistribution of soil organic matter by permafrost disturbance in the Canadian High Arctic |
title_full |
Redistribution of soil organic matter by permafrost disturbance in the Canadian High Arctic |
title_fullStr |
Redistribution of soil organic matter by permafrost disturbance in the Canadian High Arctic |
title_full_unstemmed |
Redistribution of soil organic matter by permafrost disturbance in the Canadian High Arctic |
title_sort |
redistribution of soil organic matter by permafrost disturbance in the canadian high arctic |
publisher |
Springer International Publishing |
publishDate |
2016 |
url |
http://hdl.handle.net/1807/81096 https://doi.org/10.1007/s10533-016-0215-7 |
long_lat |
ENVELOPE(-109.542,-109.542,74.863,74.863) |
geographic |
Arctic Nunavut Canada Cape Bounty |
geographic_facet |
Arctic Nunavut Canada Cape Bounty |
genre |
Arctic Nunavut permafrost |
genre_facet |
Arctic Nunavut permafrost |
op_relation |
0168-2563 http://hdl.handle.net/1807/81096 doi:10.1007/s10533-016-0215-7 |
op_doi |
https://doi.org/10.1007/s10533-016-0215-7 |
container_title |
Biogeochemistry |
container_volume |
128 |
container_issue |
3 |
container_start_page |
397 |
op_container_end_page |
415 |
_version_ |
1766323009776254976 |