Distinguishing between old and modern permafrost sources in the northeast Siberian land–shelf system with compound-specific δ 2 H analysis
Pleistocene ice complex permafrost deposits contain roughly a quarter of the organic carbon (OC) stored in permafrost (PF) terrain. When permafrost thaws, its OC is remobilized into the (aquatic) environment where it is available for degradation, transport or burial. Aquatic or coastal environments...
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ftdoajarticles:oai:doaj.org/article:3ff96b288b554ba79376152b8e44e340 2023-05-15T15:03:53+02:00 Distinguishing between old and modern permafrost sources in the northeast Siberian land–shelf system with compound-specific δ 2 H analysis J. E. Vonk T. Tesi L. Bröder H. Holmstrand G. Hugelius A. Andersson O. Dudarev I. Semiletov Ö. Gustafsson 2017-08-01T00:00:00Z https://doi.org/10.5194/tc-11-1879-2017 https://doaj.org/article/3ff96b288b554ba79376152b8e44e340 EN eng Copernicus Publications https://www.the-cryosphere.net/11/1879/2017/tc-11-1879-2017.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-11-1879-2017 1994-0416 1994-0424 https://doaj.org/article/3ff96b288b554ba79376152b8e44e340 The Cryosphere, Vol 11, Pp 1879-1895 (2017) Environmental sciences GE1-350 Geology QE1-996.5 article 2017 ftdoajarticles https://doi.org/10.5194/tc-11-1879-2017 2022-12-31T02:27:28Z Pleistocene ice complex permafrost deposits contain roughly a quarter of the organic carbon (OC) stored in permafrost (PF) terrain. When permafrost thaws, its OC is remobilized into the (aquatic) environment where it is available for degradation, transport or burial. Aquatic or coastal environments contain sedimentary reservoirs that can serve as archives of past climatic change. As permafrost thaw is increasing throughout the Arctic, these reservoirs are important locations to assess the fate of remobilized permafrost OC. We here present compound-specific deuterium ( δ 2 H) analysis on leaf waxes as a tool to distinguish between OC released from thawing Pleistocene permafrost (ice complex deposits; ICD) and from thawing Holocene permafrost (from near-surface soils). Bulk geochemistry (%OC; δ 13 C; %total nitrogen, TN) was analyzed as well as the concentrations and δ 2 H signatures of long-chain n -alkanes (C 21 to C 33 ) and mid- to long-chain n -alkanoic acids (C 16 to C 30 ) extracted from both ICD-PF samples ( n = 9) and modern vegetation and O-horizon (topsoil-PF) samples ( n = 9) from across the northeast Siberian Arctic. Results show that these topsoil-PF samples have higher %OC, higher OC ∕ TN values and more depleted δ 13 C-OC values than ICD-PF samples, suggesting that these former samples trace a fresher soil and/or vegetation source. Whereas the two investigated sources differ on the bulk geochemical level, they are, however, virtually indistinguishable when using leaf wax concentrations and ratios. However, on the molecular isotope level, leaf wax biomarker δ 2 H values are statistically different between topsoil PF and ICD PF. For example, the mean δ 2 H value of C 29 n -alkane was −246 ± 13 ‰ (mean ± SD) for topsoil PF and −280 ± 12 ‰ for ICD PF. With a dynamic isotopic range (difference between two sources) of 34 to 50 ‰; the isotopic fingerprints of individual, abundant, biomarker molecules from leaf waxes can thus serve as endmembers to distinguish between these two sources. We tested this ... Article in Journal/Newspaper Arctic Ice permafrost The Cryosphere Directory of Open Access Journals: DOAJ Articles Arctic The Cryosphere 11 4 1879 1895 |
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Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Environmental sciences GE1-350 Geology QE1-996.5 |
spellingShingle |
Environmental sciences GE1-350 Geology QE1-996.5 J. E. Vonk T. Tesi L. Bröder H. Holmstrand G. Hugelius A. Andersson O. Dudarev I. Semiletov Ö. Gustafsson Distinguishing between old and modern permafrost sources in the northeast Siberian land–shelf system with compound-specific δ 2 H analysis |
topic_facet |
Environmental sciences GE1-350 Geology QE1-996.5 |
description |
Pleistocene ice complex permafrost deposits contain roughly a quarter of the organic carbon (OC) stored in permafrost (PF) terrain. When permafrost thaws, its OC is remobilized into the (aquatic) environment where it is available for degradation, transport or burial. Aquatic or coastal environments contain sedimentary reservoirs that can serve as archives of past climatic change. As permafrost thaw is increasing throughout the Arctic, these reservoirs are important locations to assess the fate of remobilized permafrost OC. We here present compound-specific deuterium ( δ 2 H) analysis on leaf waxes as a tool to distinguish between OC released from thawing Pleistocene permafrost (ice complex deposits; ICD) and from thawing Holocene permafrost (from near-surface soils). Bulk geochemistry (%OC; δ 13 C; %total nitrogen, TN) was analyzed as well as the concentrations and δ 2 H signatures of long-chain n -alkanes (C 21 to C 33 ) and mid- to long-chain n -alkanoic acids (C 16 to C 30 ) extracted from both ICD-PF samples ( n = 9) and modern vegetation and O-horizon (topsoil-PF) samples ( n = 9) from across the northeast Siberian Arctic. Results show that these topsoil-PF samples have higher %OC, higher OC ∕ TN values and more depleted δ 13 C-OC values than ICD-PF samples, suggesting that these former samples trace a fresher soil and/or vegetation source. Whereas the two investigated sources differ on the bulk geochemical level, they are, however, virtually indistinguishable when using leaf wax concentrations and ratios. However, on the molecular isotope level, leaf wax biomarker δ 2 H values are statistically different between topsoil PF and ICD PF. For example, the mean δ 2 H value of C 29 n -alkane was −246 ± 13 ‰ (mean ± SD) for topsoil PF and −280 ± 12 ‰ for ICD PF. With a dynamic isotopic range (difference between two sources) of 34 to 50 ‰; the isotopic fingerprints of individual, abundant, biomarker molecules from leaf waxes can thus serve as endmembers to distinguish between these two sources. We tested this ... |
format |
Article in Journal/Newspaper |
author |
J. E. Vonk T. Tesi L. Bröder H. Holmstrand G. Hugelius A. Andersson O. Dudarev I. Semiletov Ö. Gustafsson |
author_facet |
J. E. Vonk T. Tesi L. Bröder H. Holmstrand G. Hugelius A. Andersson O. Dudarev I. Semiletov Ö. Gustafsson |
author_sort |
J. E. Vonk |
title |
Distinguishing between old and modern permafrost sources in the northeast Siberian land–shelf system with compound-specific δ 2 H analysis |
title_short |
Distinguishing between old and modern permafrost sources in the northeast Siberian land–shelf system with compound-specific δ 2 H analysis |
title_full |
Distinguishing between old and modern permafrost sources in the northeast Siberian land–shelf system with compound-specific δ 2 H analysis |
title_fullStr |
Distinguishing between old and modern permafrost sources in the northeast Siberian land–shelf system with compound-specific δ 2 H analysis |
title_full_unstemmed |
Distinguishing between old and modern permafrost sources in the northeast Siberian land–shelf system with compound-specific δ 2 H analysis |
title_sort |
distinguishing between old and modern permafrost sources in the northeast siberian land–shelf system with compound-specific δ 2 h analysis |
publisher |
Copernicus Publications |
publishDate |
2017 |
url |
https://doi.org/10.5194/tc-11-1879-2017 https://doaj.org/article/3ff96b288b554ba79376152b8e44e340 |
geographic |
Arctic |
geographic_facet |
Arctic |
genre |
Arctic Ice permafrost The Cryosphere |
genre_facet |
Arctic Ice permafrost The Cryosphere |
op_source |
The Cryosphere, Vol 11, Pp 1879-1895 (2017) |
op_relation |
https://www.the-cryosphere.net/11/1879/2017/tc-11-1879-2017.pdf https://doaj.org/toc/1994-0416 https://doaj.org/toc/1994-0424 doi:10.5194/tc-11-1879-2017 1994-0416 1994-0424 https://doaj.org/article/3ff96b288b554ba79376152b8e44e340 |
op_doi |
https://doi.org/10.5194/tc-11-1879-2017 |
container_title |
The Cryosphere |
container_volume |
11 |
container_issue |
4 |
container_start_page |
1879 |
op_container_end_page |
1895 |
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1766335730542444544 |