Thermokarst Lagoons: A Core-Based Assessment of Depositional Characteristics and an Estimate of Carbon Pools on the Bykovsky Peninsula
Permafrost region subsurface organic carbon (OC) pools are a major component of the terrestrial carbon cycle and vulnerable to a warming climate. Thermokarst lagoons are an important transition stage with complex depositional histories during which permafrost and lacustrine carbon pools are transfor...
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Online Access: | http://dx.doi.org/10.3389/feart.2021.637899 https://www.frontiersin.org/articles/10.3389/feart.2021.637899/full |
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crfrontiers:10.3389/feart.2021.637899 2024-10-06T13:46:30+00:00 Thermokarst Lagoons: A Core-Based Assessment of Depositional Characteristics and an Estimate of Carbon Pools on the Bykovsky Peninsula Jenrich, Maren Angelopoulos, Michael Grosse, Guido Overduin, Pier Paul Schirrmeister, Lutz Nitze, Ingmar Biskaborn, Boris K. Liebner, Susanne Grigoriev, Mikhail Murray, Andrew Jongejans, Loeka L. Strauss, Jens Bundesministerium für Bildung und Forschung European Research Council 2021 http://dx.doi.org/10.3389/feart.2021.637899 https://www.frontiersin.org/articles/10.3389/feart.2021.637899/full unknown Frontiers Media SA https://creativecommons.org/licenses/by/4.0/ Frontiers in Earth Science volume 9 ISSN 2296-6463 journal-article 2021 crfrontiers https://doi.org/10.3389/feart.2021.637899 2024-09-10T04:05:19Z Permafrost region subsurface organic carbon (OC) pools are a major component of the terrestrial carbon cycle and vulnerable to a warming climate. Thermokarst lagoons are an important transition stage with complex depositional histories during which permafrost and lacustrine carbon pools are transformed along eroding Arctic coasts. The effects of temperature and salinity changes during thermokarst lake to lagoon transitions on thaw history and lagoon deposits are understudied. We analyzed two 30-m-long sediment cores from two thermokarst lagoons on the Bykovsky Peninsula, Northeast Siberia, using sedimentological, geochronological, hydrochemical, and biogeochemical techniques. Using remote sensing we distinguished between a semi-closed and a nearly closed lagoon. We (1) characterized the depositional history, (2) studied the impact of marine inundation on ice-bearing permafrost and taliks, and (3) quantified the OC pools for different stages of thermokarst lagoons. Fluvial and former Yedoma deposits were found at depth between 30 and 8.5 m, while lake and lagoon deposits formed the upper layers. The electrical conductivity of the pore water indicated hypersaline conditions for the semi-closed lagoon (max: 108 mS/cm), while fresh to brackish conditions were observed beneath a 5 m-thick surface saline layer at the nearly closed lagoon. The deposits had a mean OC content of 15 ± 2 kg/m 3 , with higher values in the semi-closed lagoon. Based on the cores we estimated a total OC pool of 5.7 Mt-C for the first 30 m of sediment below five mapped lagoons on the Bykovsky Peninsula. Our results suggest that paleo river branches shaped the middle Pleistocene landscape followed by late Pleistocene Yedoma permafrost accumulation and early Holocene lake development. Afterward, lake drainage, marine flooding, and bedfast ice formation caused the saline enrichment of pore water, which led to cryotic talik development. We find that the OC-pool of Arctic lagoons may comprise a substantial inventory of partially thawed and ... Article in Journal/Newspaper Arctic Ice permafrost Thermokarst Siberia Frontiers (Publisher) Arctic Talik ENVELOPE(146.601,146.601,59.667,59.667) Frontiers in Earth Science 9 |
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Frontiers (Publisher) |
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description |
Permafrost region subsurface organic carbon (OC) pools are a major component of the terrestrial carbon cycle and vulnerable to a warming climate. Thermokarst lagoons are an important transition stage with complex depositional histories during which permafrost and lacustrine carbon pools are transformed along eroding Arctic coasts. The effects of temperature and salinity changes during thermokarst lake to lagoon transitions on thaw history and lagoon deposits are understudied. We analyzed two 30-m-long sediment cores from two thermokarst lagoons on the Bykovsky Peninsula, Northeast Siberia, using sedimentological, geochronological, hydrochemical, and biogeochemical techniques. Using remote sensing we distinguished between a semi-closed and a nearly closed lagoon. We (1) characterized the depositional history, (2) studied the impact of marine inundation on ice-bearing permafrost and taliks, and (3) quantified the OC pools for different stages of thermokarst lagoons. Fluvial and former Yedoma deposits were found at depth between 30 and 8.5 m, while lake and lagoon deposits formed the upper layers. The electrical conductivity of the pore water indicated hypersaline conditions for the semi-closed lagoon (max: 108 mS/cm), while fresh to brackish conditions were observed beneath a 5 m-thick surface saline layer at the nearly closed lagoon. The deposits had a mean OC content of 15 ± 2 kg/m 3 , with higher values in the semi-closed lagoon. Based on the cores we estimated a total OC pool of 5.7 Mt-C for the first 30 m of sediment below five mapped lagoons on the Bykovsky Peninsula. Our results suggest that paleo river branches shaped the middle Pleistocene landscape followed by late Pleistocene Yedoma permafrost accumulation and early Holocene lake development. Afterward, lake drainage, marine flooding, and bedfast ice formation caused the saline enrichment of pore water, which led to cryotic talik development. We find that the OC-pool of Arctic lagoons may comprise a substantial inventory of partially thawed and ... |
author2 |
Bundesministerium für Bildung und Forschung European Research Council |
format |
Article in Journal/Newspaper |
author |
Jenrich, Maren Angelopoulos, Michael Grosse, Guido Overduin, Pier Paul Schirrmeister, Lutz Nitze, Ingmar Biskaborn, Boris K. Liebner, Susanne Grigoriev, Mikhail Murray, Andrew Jongejans, Loeka L. Strauss, Jens |
spellingShingle |
Jenrich, Maren Angelopoulos, Michael Grosse, Guido Overduin, Pier Paul Schirrmeister, Lutz Nitze, Ingmar Biskaborn, Boris K. Liebner, Susanne Grigoriev, Mikhail Murray, Andrew Jongejans, Loeka L. Strauss, Jens Thermokarst Lagoons: A Core-Based Assessment of Depositional Characteristics and an Estimate of Carbon Pools on the Bykovsky Peninsula |
author_facet |
Jenrich, Maren Angelopoulos, Michael Grosse, Guido Overduin, Pier Paul Schirrmeister, Lutz Nitze, Ingmar Biskaborn, Boris K. Liebner, Susanne Grigoriev, Mikhail Murray, Andrew Jongejans, Loeka L. Strauss, Jens |
author_sort |
Jenrich, Maren |
title |
Thermokarst Lagoons: A Core-Based Assessment of Depositional Characteristics and an Estimate of Carbon Pools on the Bykovsky Peninsula |
title_short |
Thermokarst Lagoons: A Core-Based Assessment of Depositional Characteristics and an Estimate of Carbon Pools on the Bykovsky Peninsula |
title_full |
Thermokarst Lagoons: A Core-Based Assessment of Depositional Characteristics and an Estimate of Carbon Pools on the Bykovsky Peninsula |
title_fullStr |
Thermokarst Lagoons: A Core-Based Assessment of Depositional Characteristics and an Estimate of Carbon Pools on the Bykovsky Peninsula |
title_full_unstemmed |
Thermokarst Lagoons: A Core-Based Assessment of Depositional Characteristics and an Estimate of Carbon Pools on the Bykovsky Peninsula |
title_sort |
thermokarst lagoons: a core-based assessment of depositional characteristics and an estimate of carbon pools on the bykovsky peninsula |
publisher |
Frontiers Media SA |
publishDate |
2021 |
url |
http://dx.doi.org/10.3389/feart.2021.637899 https://www.frontiersin.org/articles/10.3389/feart.2021.637899/full |
long_lat |
ENVELOPE(146.601,146.601,59.667,59.667) |
geographic |
Arctic Talik |
geographic_facet |
Arctic Talik |
genre |
Arctic Ice permafrost Thermokarst Siberia |
genre_facet |
Arctic Ice permafrost Thermokarst Siberia |
op_source |
Frontiers in Earth Science volume 9 ISSN 2296-6463 |
op_rights |
https://creativecommons.org/licenses/by/4.0/ |
op_doi |
https://doi.org/10.3389/feart.2021.637899 |
container_title |
Frontiers in Earth Science |
container_volume |
9 |
_version_ |
1812174816718880768 |