Large amounts of labile organic carbon in permafrost soils of northern Alaska
Permafrost-affected soils of the northern circumpolar region represent 50% of the terrestrial soil organic carbon (SOC) reservoir and are most strongly affected by climatic change. There is growing concern that this vast SOC pool could transition from a net C sink to a source. But so far little is k...
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ftubkoeln:oai:USBKOELN.ub.uni-koeln.de:40035 2023-05-15T15:11:49+02:00 Large amounts of labile organic carbon in permafrost soils of northern Alaska Mueller, Carsten W. Rethemeyer, Janet Kao-Kniffin, Jenny Loeppmann, Sebastian Hinkel, Kenneth M. G. Bockheim, James 2015 https://kups.ub.uni-koeln.de/40035/ eng eng WILEY Mueller, Carsten W., Rethemeyer, Janet orcid:0000-0001-6698-4186 , Kao-Kniffin, Jenny, Loeppmann, Sebastian, Hinkel, Kenneth M. and G. Bockheim, James (2015). Large amounts of labile organic carbon in permafrost soils of northern Alaska. Glob. Change Biol., 21 (7). S. 2804 - 2818. HOBOKEN: WILEY. ISSN 1365-2486 ddc:no doc-type:article publishedVersion 2015 ftubkoeln 2022-11-09T07:26:37Z Permafrost-affected soils of the northern circumpolar region represent 50% of the terrestrial soil organic carbon (SOC) reservoir and are most strongly affected by climatic change. There is growing concern that this vast SOC pool could transition from a net C sink to a source. But so far little is known on how the organic matter (OM) in permafrost soils will respond in a warming future, which is governed by OM composition and possible stabilization mechanisms. To investigate if and how SOC in the active layer and adjacent permafrost is protected against degradation, we employed density fractionation to separate differently stabilized SOM fractions. We studied the quantity and quality of OM in different compartments using elemental analysis, C-13 solid-phase nuclear magnetic resonance (C-13-NMR) spectroscopy, and C-14 analyses. The soil samples were derived from 16 cores from drained thaw lake basins, ranging from 0 to 5500years of age, representing a unique series of developing Arctic soils over time. The normalized SOC stocks ranged between 35.5 and 86.2kgSOCm(-3), with the major amount of SOC located in the active layers. The SOC stock is dominated by large amounts of particulate organic matter (POM), whereas mineral-associated OM especially in older soils is of minor importance on a mass basis. We show that tremendous amounts of over 25kgOC per square meter are stored as presumably easily degradable OM rich in carbohydrates. Only about 10kgOC per square meter is present as presumably more stable, mineral-associated OC. Significant amounts of the easily degradable, carbohydrate-rich OM are preserved in the yet permanently frozen soil below the permafrost table. Forced by global warming, this vast labile OM pool could soon become available for microbial degradation due to the continuous deepening of the annually thawing active layer. Article in Journal/Newspaper Arctic Global warming permafrost Alaska Cologne University: KUPS Arctic |
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Cologne University: KUPS |
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English |
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ddc:no Mueller, Carsten W. Rethemeyer, Janet Kao-Kniffin, Jenny Loeppmann, Sebastian Hinkel, Kenneth M. G. Bockheim, James Large amounts of labile organic carbon in permafrost soils of northern Alaska |
topic_facet |
ddc:no |
description |
Permafrost-affected soils of the northern circumpolar region represent 50% of the terrestrial soil organic carbon (SOC) reservoir and are most strongly affected by climatic change. There is growing concern that this vast SOC pool could transition from a net C sink to a source. But so far little is known on how the organic matter (OM) in permafrost soils will respond in a warming future, which is governed by OM composition and possible stabilization mechanisms. To investigate if and how SOC in the active layer and adjacent permafrost is protected against degradation, we employed density fractionation to separate differently stabilized SOM fractions. We studied the quantity and quality of OM in different compartments using elemental analysis, C-13 solid-phase nuclear magnetic resonance (C-13-NMR) spectroscopy, and C-14 analyses. The soil samples were derived from 16 cores from drained thaw lake basins, ranging from 0 to 5500years of age, representing a unique series of developing Arctic soils over time. The normalized SOC stocks ranged between 35.5 and 86.2kgSOCm(-3), with the major amount of SOC located in the active layers. The SOC stock is dominated by large amounts of particulate organic matter (POM), whereas mineral-associated OM especially in older soils is of minor importance on a mass basis. We show that tremendous amounts of over 25kgOC per square meter are stored as presumably easily degradable OM rich in carbohydrates. Only about 10kgOC per square meter is present as presumably more stable, mineral-associated OC. Significant amounts of the easily degradable, carbohydrate-rich OM are preserved in the yet permanently frozen soil below the permafrost table. Forced by global warming, this vast labile OM pool could soon become available for microbial degradation due to the continuous deepening of the annually thawing active layer. |
format |
Article in Journal/Newspaper |
author |
Mueller, Carsten W. Rethemeyer, Janet Kao-Kniffin, Jenny Loeppmann, Sebastian Hinkel, Kenneth M. G. Bockheim, James |
author_facet |
Mueller, Carsten W. Rethemeyer, Janet Kao-Kniffin, Jenny Loeppmann, Sebastian Hinkel, Kenneth M. G. Bockheim, James |
author_sort |
Mueller, Carsten W. |
title |
Large amounts of labile organic carbon in permafrost soils of northern Alaska |
title_short |
Large amounts of labile organic carbon in permafrost soils of northern Alaska |
title_full |
Large amounts of labile organic carbon in permafrost soils of northern Alaska |
title_fullStr |
Large amounts of labile organic carbon in permafrost soils of northern Alaska |
title_full_unstemmed |
Large amounts of labile organic carbon in permafrost soils of northern Alaska |
title_sort |
large amounts of labile organic carbon in permafrost soils of northern alaska |
publisher |
WILEY |
publishDate |
2015 |
url |
https://kups.ub.uni-koeln.de/40035/ |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Global warming permafrost Alaska |
genre_facet |
Arctic Global warming permafrost Alaska |
op_relation |
Mueller, Carsten W., Rethemeyer, Janet orcid:0000-0001-6698-4186 , Kao-Kniffin, Jenny, Loeppmann, Sebastian, Hinkel, Kenneth M. and G. Bockheim, James (2015). Large amounts of labile organic carbon in permafrost soils of northern Alaska. Glob. Change Biol., 21 (7). S. 2804 - 2818. HOBOKEN: WILEY. ISSN 1365-2486 |
_version_ |
1766342601965830144 |