High methane emissions from thermokarst lakes in subarctic peatlands.
La transcription des symboles et des caractères spéciaux utilisés dans la version originale de ce résumé n’a pas été possible en raison de limitations techniques. La version correcte de ce résumé peut être lue dans le document original. The thawing and subsidence of frozen peat mounds (palsas) in pe...
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Online Access: | https://espace.inrs.ca/id/eprint/5700/ https://doi.org/10.1002/lno.10311 |
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ftinrsquebec:oai:espace.inrs.ca:5700 2023-07-02T03:33:24+02:00 High methane emissions from thermokarst lakes in subarctic peatlands. Matveev, Alex Laurion, Isabelle Deshpande, Bethany N. Bhiry, Najat Vincent, Warwick 2016 https://espace.inrs.ca/id/eprint/5700/ https://doi.org/10.1002/lno.10311 unknown Matveev, Alex, Laurion, Isabelle, Deshpande, Bethany N., Bhiry, Najat et Vincent, Warwick (2016). High methane emissions from thermokarst lakes in subarctic peatlands. Limnology and Oceanography , vol. 61 , nº S1. S150-S164. DOI:10.1002/lno.10311 <https://doi.org/10.1002/lno.10311>. doi:10.1002/lno.10311 carbon emission concentration (composition) emission greenhouse gas lacustrine environment methane palsa peat peatland permafrost radiocarbon dating subarctic region subsidence thawing thermokarst water column Article Évalué par les pairs 2016 ftinrsquebec https://doi.org/10.1002/lno.10311 2023-06-10T23:12:39Z La transcription des symboles et des caractères spéciaux utilisés dans la version originale de ce résumé n’a pas été possible en raison de limitations techniques. La version correcte de ce résumé peut être lue dans le document original. The thawing and subsidence of frozen peat mounds (palsas) in permafrost landscapes results in the formation of organic-rich thermokarst lakes. We examined the effects of palsa degradation on CH4 and CO2 emissions by comparing thermokarst lakes at two peatland locations in subarctic Québec, Canada: in the northern discontinuous permafrost region, and in southern sporadic permafrost where palsas are more rapidly degrading. The lakes were shallow (< 3 m) but stratified at both sites, and most had anoxic bottom waters. The surface waters at both sites were supersaturated in CH4 and CO2, and to a greater extent in the southern lakes, where the surface CH4 concentrations were up to 3 orders of magnitude above air equilibrium. Concentrations of CH4 and CO2 increased by orders of magnitude with depth in the southern lakes, however these gradients were less marked or absent in the North. Strong CH4 and CO2 emissions were associated with gas ebullition, but these were greatly exceeded by diffusive fluxes, in contrast to thermokarst lakes studied elsewhere. Also unusual relative to other studies to date, the surface concentrations of both gases increased as a linear function of water column depth, with highest values over the central, deepest portion of the lakes. Radiocarbon dating of ebullition gas samples showed that the CH4 had 14C-ages from 760 yr to 2005 yr before present, while the CO2 was consistently younger. Peatland thermokarst lakes may be an increasingly important source of greenhouse gases as the southern permafrost limit continues to shift northwards. Article in Journal/Newspaper palsa palsas permafrost Subarctic Thermokarst Institut national de la recherche scientifique, Québec: Espace INRS Canada Limnology and Oceanography 61 S1 S150 S164 |
institution |
Open Polar |
collection |
Institut national de la recherche scientifique, Québec: Espace INRS |
op_collection_id |
ftinrsquebec |
language |
unknown |
topic |
carbon emission concentration (composition) emission greenhouse gas lacustrine environment methane palsa peat peatland permafrost radiocarbon dating subarctic region subsidence thawing thermokarst water column |
spellingShingle |
carbon emission concentration (composition) emission greenhouse gas lacustrine environment methane palsa peat peatland permafrost radiocarbon dating subarctic region subsidence thawing thermokarst water column Matveev, Alex Laurion, Isabelle Deshpande, Bethany N. Bhiry, Najat Vincent, Warwick High methane emissions from thermokarst lakes in subarctic peatlands. |
topic_facet |
carbon emission concentration (composition) emission greenhouse gas lacustrine environment methane palsa peat peatland permafrost radiocarbon dating subarctic region subsidence thawing thermokarst water column |
description |
La transcription des symboles et des caractères spéciaux utilisés dans la version originale de ce résumé n’a pas été possible en raison de limitations techniques. La version correcte de ce résumé peut être lue dans le document original. The thawing and subsidence of frozen peat mounds (palsas) in permafrost landscapes results in the formation of organic-rich thermokarst lakes. We examined the effects of palsa degradation on CH4 and CO2 emissions by comparing thermokarst lakes at two peatland locations in subarctic Québec, Canada: in the northern discontinuous permafrost region, and in southern sporadic permafrost where palsas are more rapidly degrading. The lakes were shallow (< 3 m) but stratified at both sites, and most had anoxic bottom waters. The surface waters at both sites were supersaturated in CH4 and CO2, and to a greater extent in the southern lakes, where the surface CH4 concentrations were up to 3 orders of magnitude above air equilibrium. Concentrations of CH4 and CO2 increased by orders of magnitude with depth in the southern lakes, however these gradients were less marked or absent in the North. Strong CH4 and CO2 emissions were associated with gas ebullition, but these were greatly exceeded by diffusive fluxes, in contrast to thermokarst lakes studied elsewhere. Also unusual relative to other studies to date, the surface concentrations of both gases increased as a linear function of water column depth, with highest values over the central, deepest portion of the lakes. Radiocarbon dating of ebullition gas samples showed that the CH4 had 14C-ages from 760 yr to 2005 yr before present, while the CO2 was consistently younger. Peatland thermokarst lakes may be an increasingly important source of greenhouse gases as the southern permafrost limit continues to shift northwards. |
format |
Article in Journal/Newspaper |
author |
Matveev, Alex Laurion, Isabelle Deshpande, Bethany N. Bhiry, Najat Vincent, Warwick |
author_facet |
Matveev, Alex Laurion, Isabelle Deshpande, Bethany N. Bhiry, Najat Vincent, Warwick |
author_sort |
Matveev, Alex |
title |
High methane emissions from thermokarst lakes in subarctic peatlands. |
title_short |
High methane emissions from thermokarst lakes in subarctic peatlands. |
title_full |
High methane emissions from thermokarst lakes in subarctic peatlands. |
title_fullStr |
High methane emissions from thermokarst lakes in subarctic peatlands. |
title_full_unstemmed |
High methane emissions from thermokarst lakes in subarctic peatlands. |
title_sort |
high methane emissions from thermokarst lakes in subarctic peatlands. |
publishDate |
2016 |
url |
https://espace.inrs.ca/id/eprint/5700/ https://doi.org/10.1002/lno.10311 |
geographic |
Canada |
geographic_facet |
Canada |
genre |
palsa palsas permafrost Subarctic Thermokarst |
genre_facet |
palsa palsas permafrost Subarctic Thermokarst |
op_relation |
Matveev, Alex, Laurion, Isabelle, Deshpande, Bethany N., Bhiry, Najat et Vincent, Warwick (2016). High methane emissions from thermokarst lakes in subarctic peatlands. Limnology and Oceanography , vol. 61 , nº S1. S150-S164. DOI:10.1002/lno.10311 <https://doi.org/10.1002/lno.10311>. doi:10.1002/lno.10311 |
op_doi |
https://doi.org/10.1002/lno.10311 |
container_title |
Limnology and Oceanography |
container_volume |
61 |
container_issue |
S1 |
container_start_page |
S150 |
op_container_end_page |
S164 |
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1770273343170150400 |