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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ftdoajarticles:oai:doaj.org/article:9ed9ce9d1ae64513a7e1dd5c49822a72 2023-05-15T14:56:51+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 L. Bröder T. Tesi J. A. Salvadó I. P. Semiletov O. V. Dudarev Ö. Gustafsson 2016-09-01T00:00:00Z https://doi.org/10.5194/bg-13-5003-2016 https://doaj.org/article/9ed9ce9d1ae64513a7e1dd5c49822a72 EN eng Copernicus Publications http://www.biogeosciences.net/13/5003/2016/bg-13-5003-2016.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 1726-4170 1726-4189 doi:10.5194/bg-13-5003-2016 https://doaj.org/article/9ed9ce9d1ae64513a7e1dd5c49822a72 Biogeosciences, Vol 13, Iss 17, Pp 5003-5019 (2016) Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 article 2016 ftdoajarticles https://doi.org/10.5194/bg-13-5003-2016 2022-12-31T14:24:36Z 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. Article in Journal/Newspaper Arctic Climate change Global warming laptev Laptev Sea lena river permafrost Directory of Open Access Journals: DOAJ Articles Arctic Laptev Sea Biogeosciences 13 17 5003 5019 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 |
spellingShingle |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 L. Bröder T. Tesi J. A. Salvadó I. P. Semiletov O. V. Dudarev Ö. Gustafsson Fate of terrigenous organic matter across the Laptev Sea from the mouth of the Lena River to the deep sea of the Arctic interior |
topic_facet |
Ecology QH540-549.5 Life QH501-531 Geology QE1-996.5 |
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 |
Article in Journal/Newspaper |
author |
L. Bröder T. Tesi J. A. Salvadó I. P. Semiletov O. V. Dudarev Ö. Gustafsson |
author_facet |
L. Bröder T. Tesi J. A. Salvadó I. P. Semiletov O. V. Dudarev Ö. Gustafsson |
author_sort |
L. Bröder |
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 |
publisher |
Copernicus Publications |
publishDate |
2016 |
url |
https://doi.org/10.5194/bg-13-5003-2016 https://doaj.org/article/9ed9ce9d1ae64513a7e1dd5c49822a72 |
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 |
Biogeosciences, Vol 13, Iss 17, Pp 5003-5019 (2016) |
op_relation |
http://www.biogeosciences.net/13/5003/2016/bg-13-5003-2016.pdf https://doaj.org/toc/1726-4170 https://doaj.org/toc/1726-4189 1726-4170 1726-4189 doi:10.5194/bg-13-5003-2016 https://doaj.org/article/9ed9ce9d1ae64513a7e1dd5c49822a72 |
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 |
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1766328919604068352 |