Macromolecular composition of terrestrial and marine organic matter in sediments across the East Siberian Arctic Shelf
Mobilisation of terrestrial organic carbon (terrOC) from permafrost environments in eastern Siberia has the potential to deliver significant amounts of carbon to the Arctic Ocean, via both fluvial and coastal erosion. Eroded terrOC can be degraded during offshore transport or deposited across the wi...
Published in: | The Cryosphere |
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2016
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Online Access: | https://research.manchester.ac.uk/en/publications/ddc4e7be-3f72-4705-9a1e-cca40a3c5bf9 https://doi.org/10.5194/tc-10-2485-2016 |
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ftumanchesterpub:oai:pure.atira.dk:publications/ddc4e7be-3f72-4705-9a1e-cca40a3c5bf9 2023-11-12T04:09:56+01:00 Macromolecular composition of terrestrial and marine organic matter in sediments across the East Siberian Arctic Shelf Sparkes, Robert B. Doĝrul Selver, Ayça Gustafsson, Örjan Semiletov , Igor P. Haghipour, Negar Wacker, Lukas Eglinton, Timothy I Talbot, Helen M. van Dongen, B E 2016 https://research.manchester.ac.uk/en/publications/ddc4e7be-3f72-4705-9a1e-cca40a3c5bf9 https://doi.org/10.5194/tc-10-2485-2016 eng eng info:eu-repo/semantics/openAccess Sparkes , R B , Doĝrul Selver , A , Gustafsson , Ö , Semiletov , I P , Haghipour , N , Wacker , L , Eglinton , T I , Talbot , H M & van Dongen , B E 2016 , ' Macromolecular composition of terrestrial and marine organic matter in sediments across the East Siberian Arctic Shelf ' , Cryosphere , vol. 10 , pp. 2485-2500 . https://doi.org/10.5194/tc-10-2485-2016 article 2016 ftumanchesterpub https://doi.org/10.5194/tc-10-2485-2016 2023-10-30T09:13:07Z Mobilisation of terrestrial organic carbon (terrOC) from permafrost environments in eastern Siberia has the potential to deliver significant amounts of carbon to the Arctic Ocean, via both fluvial and coastal erosion. Eroded terrOC can be degraded during offshore transport or deposited across the wide East Siberian Arctic Shelf (ESAS). Most studies of terrOC on the ESAS have concentrated on solvent-extractable organic matter, but this represents only a small proportion of the total terrOC load. In this study we have used pyrolysis–gas chromatography–mass spectrometry (py-GCMS) to study all major groups of macromolecular components of the terrOC; this is the first time that this technique has been applied to the ESAS. This has shown that there is a strong offshore trend from terrestrial phenols, aromatics and cyclopentenones to marine pyridines. There is good agreement between proportion phenols measured using py-GCMS and independent quantification of lignin phenol concentrations ( r 2 = 0.67, p < 0.01, n = 24). Furfurals, thought to represent carbohydrates, show no offshore trend and are likely found in both marine and terrestrial organic matter. We have also collected new radiocarbon data for bulk OC ( 14 COC) which, when coupled with previous measurements, allows us to produce the most comprehensive 14 COC map of the ESAS to date. Combining the 14 COC and py-GCMS data suggests that the aromatics group of compounds is likely sourced from old, aged terrOC, in contrast to the phenols group, which is likely sourced from modern woody material. We propose that an index of the relative proportions of phenols and pyridines can be used as a novel terrestrial vs. marine proxy measurement for macromolecular organic matter. Principal component analysis found that various terrestrial vs. marine proxies show different patterns across the ESAS, and it shows that multiple river–ocean transects of surface sediments transition from river-dominated to coastal-erosion-dominated to marine-dominated signatures. Article in Journal/Newspaper Arctic Arctic Arctic Ocean permafrost Siberia The University of Manchester: Research Explorer Arctic Arctic Ocean The Cryosphere 10 5 2485 2500 |
institution |
Open Polar |
collection |
The University of Manchester: Research Explorer |
op_collection_id |
ftumanchesterpub |
language |
English |
description |
Mobilisation of terrestrial organic carbon (terrOC) from permafrost environments in eastern Siberia has the potential to deliver significant amounts of carbon to the Arctic Ocean, via both fluvial and coastal erosion. Eroded terrOC can be degraded during offshore transport or deposited across the wide East Siberian Arctic Shelf (ESAS). Most studies of terrOC on the ESAS have concentrated on solvent-extractable organic matter, but this represents only a small proportion of the total terrOC load. In this study we have used pyrolysis–gas chromatography–mass spectrometry (py-GCMS) to study all major groups of macromolecular components of the terrOC; this is the first time that this technique has been applied to the ESAS. This has shown that there is a strong offshore trend from terrestrial phenols, aromatics and cyclopentenones to marine pyridines. There is good agreement between proportion phenols measured using py-GCMS and independent quantification of lignin phenol concentrations ( r 2 = 0.67, p < 0.01, n = 24). Furfurals, thought to represent carbohydrates, show no offshore trend and are likely found in both marine and terrestrial organic matter. We have also collected new radiocarbon data for bulk OC ( 14 COC) which, when coupled with previous measurements, allows us to produce the most comprehensive 14 COC map of the ESAS to date. Combining the 14 COC and py-GCMS data suggests that the aromatics group of compounds is likely sourced from old, aged terrOC, in contrast to the phenols group, which is likely sourced from modern woody material. We propose that an index of the relative proportions of phenols and pyridines can be used as a novel terrestrial vs. marine proxy measurement for macromolecular organic matter. Principal component analysis found that various terrestrial vs. marine proxies show different patterns across the ESAS, and it shows that multiple river–ocean transects of surface sediments transition from river-dominated to coastal-erosion-dominated to marine-dominated signatures. |
format |
Article in Journal/Newspaper |
author |
Sparkes, Robert B. Doĝrul Selver, Ayça Gustafsson, Örjan Semiletov , Igor P. Haghipour, Negar Wacker, Lukas Eglinton, Timothy I Talbot, Helen M. van Dongen, B E |
spellingShingle |
Sparkes, Robert B. Doĝrul Selver, Ayça Gustafsson, Örjan Semiletov , Igor P. Haghipour, Negar Wacker, Lukas Eglinton, Timothy I Talbot, Helen M. van Dongen, B E Macromolecular composition of terrestrial and marine organic matter in sediments across the East Siberian Arctic Shelf |
author_facet |
Sparkes, Robert B. Doĝrul Selver, Ayça Gustafsson, Örjan Semiletov , Igor P. Haghipour, Negar Wacker, Lukas Eglinton, Timothy I Talbot, Helen M. van Dongen, B E |
author_sort |
Sparkes, Robert B. |
title |
Macromolecular composition of terrestrial and marine organic matter in sediments across the East Siberian Arctic Shelf |
title_short |
Macromolecular composition of terrestrial and marine organic matter in sediments across the East Siberian Arctic Shelf |
title_full |
Macromolecular composition of terrestrial and marine organic matter in sediments across the East Siberian Arctic Shelf |
title_fullStr |
Macromolecular composition of terrestrial and marine organic matter in sediments across the East Siberian Arctic Shelf |
title_full_unstemmed |
Macromolecular composition of terrestrial and marine organic matter in sediments across the East Siberian Arctic Shelf |
title_sort |
macromolecular composition of terrestrial and marine organic matter in sediments across the east siberian arctic shelf |
publishDate |
2016 |
url |
https://research.manchester.ac.uk/en/publications/ddc4e7be-3f72-4705-9a1e-cca40a3c5bf9 https://doi.org/10.5194/tc-10-2485-2016 |
geographic |
Arctic Arctic Ocean |
geographic_facet |
Arctic Arctic Ocean |
genre |
Arctic Arctic Arctic Ocean permafrost Siberia |
genre_facet |
Arctic Arctic Arctic Ocean permafrost Siberia |
op_source |
Sparkes , R B , Doĝrul Selver , A , Gustafsson , Ö , Semiletov , I P , Haghipour , N , Wacker , L , Eglinton , T I , Talbot , H M & van Dongen , B E 2016 , ' Macromolecular composition of terrestrial and marine organic matter in sediments across the East Siberian Arctic Shelf ' , Cryosphere , vol. 10 , pp. 2485-2500 . https://doi.org/10.5194/tc-10-2485-2016 |
op_rights |
info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/tc-10-2485-2016 |
container_title |
The Cryosphere |
container_volume |
10 |
container_issue |
5 |
container_start_page |
2485 |
op_container_end_page |
2500 |
_version_ |
1782329667745742848 |