Fate of terrigenous organic matter across the Laptev Sea from the mouth of the Lena River to the deep sea of the Arctic interior
Ongoing global warming in high latitudes may cause an increasing supply of permafrost-derived organic carbon through both river discharge and coastal erosion to the Arctic shelves. Mobilized permafrost carbon can be either buried in sediments, transported to the deep sea or degraded to CO 2 and outg...
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ftcopernicus:oai:publications.copernicus.org:bg51045 2023-05-15T14:55:40+02:00 Fate of terrigenous organic matter across the Laptev Sea from the mouth of the Lena River to the deep sea of the Arctic interior Bröder, Lisa Tesi, Tommaso Salvadó, Joan A. Semiletov, Igor P. Dudarev, Oleg V. Gustafsson, Örjan 2018-09-27 info:eu-repo/semantics/application/pdf https://doi.org/10.5194/bg-13-5003-2016 https://www.biogeosciences.net/13/5003/2016/ eng eng info:eu-repo/grantAgreement/EC/FP7/328049 info:eu-repo/grantAgreement/EC/FP7/300259 doi:10.5194/bg-13-5003-2016 https://www.biogeosciences.net/13/5003/2016/ info:eu-repo/semantics/openAccess eISSN: 1726-4189 info:eu-repo/semantics/Text 2018 ftcopernicus https://doi.org/10.5194/bg-13-5003-2016 2019-12-24T09:52:00Z Ongoing global warming in high latitudes may cause an increasing supply of permafrost-derived organic carbon through both river discharge and coastal erosion to the Arctic shelves. Mobilized permafrost carbon can be either buried in sediments, transported to the deep sea or degraded to CO 2 and outgassed, potentially constituting a positive feedback to climate change. This study aims to assess the fate of terrigenous organic carbon (TerrOC) in the Arctic marine environment by exploring how it changes in concentration, composition and degradation status across the wide Laptev Sea shelf. We analyzed a suite of terrestrial biomarkers as well as source-diagnostic bulk carbon isotopes ( δ 13 C, Δ 14 C) in surface sediments from a Laptev Sea transect spanning more than 800 km from the Lena River mouth (< 10 m water depth) across the shelf to the slope and rise (2000–3000 m water depth). These data provide a broad view on different TerrOC pools and their behavior during cross-shelf transport. The concentrations of lignin phenols, cutin acids and high-molecular-weight (HMW) wax lipids (tracers of vascular plants) decrease by 89–99 % along the transect. Molecular-based degradation proxies for TerrOC (e.g., the carbon preference index of HMW lipids, the HMW acids ∕ alkanes ratio and the acid ∕ aldehyde ratio of lignin phenols) display a trend to more degraded TerrOC with increasing distance from the coast. We infer that the degree of degradation of permafrost-derived TerrOC is a function of the time spent under oxic conditions during protracted cross-shelf transport. Future work should therefore seek to constrain cross-shelf transport times in order to compute a TerrOC degradation rate and thereby help to quantify potential carbon–climate feedbacks. Other/Unknown Material Arctic Climate change Global warming laptev Laptev Sea lena river permafrost Copernicus Publications: E-Journals Arctic Laptev Sea Biogeosciences 13 17 5003 5019 |
institution |
Open Polar |
collection |
Copernicus Publications: E-Journals |
op_collection_id |
ftcopernicus |
language |
English |
description |
Ongoing global warming in high latitudes may cause an increasing supply of permafrost-derived organic carbon through both river discharge and coastal erosion to the Arctic shelves. Mobilized permafrost carbon can be either buried in sediments, transported to the deep sea or degraded to CO 2 and outgassed, potentially constituting a positive feedback to climate change. This study aims to assess the fate of terrigenous organic carbon (TerrOC) in the Arctic marine environment by exploring how it changes in concentration, composition and degradation status across the wide Laptev Sea shelf. We analyzed a suite of terrestrial biomarkers as well as source-diagnostic bulk carbon isotopes ( δ 13 C, Δ 14 C) in surface sediments from a Laptev Sea transect spanning more than 800 km from the Lena River mouth (< 10 m water depth) across the shelf to the slope and rise (2000–3000 m water depth). These data provide a broad view on different TerrOC pools and their behavior during cross-shelf transport. The concentrations of lignin phenols, cutin acids and high-molecular-weight (HMW) wax lipids (tracers of vascular plants) decrease by 89–99 % along the transect. Molecular-based degradation proxies for TerrOC (e.g., the carbon preference index of HMW lipids, the HMW acids ∕ alkanes ratio and the acid ∕ aldehyde ratio of lignin phenols) display a trend to more degraded TerrOC with increasing distance from the coast. We infer that the degree of degradation of permafrost-derived TerrOC is a function of the time spent under oxic conditions during protracted cross-shelf transport. Future work should therefore seek to constrain cross-shelf transport times in order to compute a TerrOC degradation rate and thereby help to quantify potential carbon–climate feedbacks. |
format |
Other/Unknown Material |
author |
Bröder, Lisa Tesi, Tommaso Salvadó, Joan A. Semiletov, Igor P. Dudarev, Oleg V. Gustafsson, Örjan |
spellingShingle |
Bröder, Lisa Tesi, Tommaso Salvadó, Joan A. Semiletov, Igor P. Dudarev, Oleg V. Gustafsson, Örjan Fate of terrigenous organic matter across the Laptev Sea from the mouth of the Lena River to the deep sea of the Arctic interior |
author_facet |
Bröder, Lisa Tesi, Tommaso Salvadó, Joan A. Semiletov, Igor P. Dudarev, Oleg V. Gustafsson, Örjan |
author_sort |
Bröder, Lisa |
title |
Fate of terrigenous organic matter across the Laptev Sea from the mouth of the Lena River to the deep sea of the Arctic interior |
title_short |
Fate of terrigenous organic matter across the Laptev Sea from the mouth of the Lena River to the deep sea of the Arctic interior |
title_full |
Fate of terrigenous organic matter across the Laptev Sea from the mouth of the Lena River to the deep sea of the Arctic interior |
title_fullStr |
Fate of terrigenous organic matter across the Laptev Sea from the mouth of the Lena River to the deep sea of the Arctic interior |
title_full_unstemmed |
Fate of terrigenous organic matter across the Laptev Sea from the mouth of the Lena River to the deep sea of the Arctic interior |
title_sort |
fate of terrigenous organic matter across the laptev sea from the mouth of the lena river to the deep sea of the arctic interior |
publishDate |
2018 |
url |
https://doi.org/10.5194/bg-13-5003-2016 https://www.biogeosciences.net/13/5003/2016/ |
geographic |
Arctic Laptev Sea |
geographic_facet |
Arctic Laptev Sea |
genre |
Arctic Climate change Global warming laptev Laptev Sea lena river permafrost |
genre_facet |
Arctic Climate change Global warming laptev Laptev Sea lena river permafrost |
op_source |
eISSN: 1726-4189 |
op_relation |
info:eu-repo/grantAgreement/EC/FP7/328049 info:eu-repo/grantAgreement/EC/FP7/300259 doi:10.5194/bg-13-5003-2016 https://www.biogeosciences.net/13/5003/2016/ |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/bg-13-5003-2016 |
container_title |
Biogeosciences |
container_volume |
13 |
container_issue |
17 |
container_start_page |
5003 |
op_container_end_page |
5019 |
_version_ |
1766327700394344448 |