Benthic Carbon Remineralization and Iron Cycling in Relation to Sea Ice Cover along the Eastern Continental Shelf of the Antarctic Peninsula
Rapid and profound climatic and environmental changes have been predicted for the Antarctic Peninsula with so far unknown impact on the biogeochemistry of the continental shelves. In this study, we investigate benthic carbon sedimentation, remineralization and iron cycling using sediment cores retri...
Published in: | Journal of Geophysical Research: Oceans |
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ftawi:oai:epic.awi.de:56460 2024-09-15T17:45:22+00:00 Benthic Carbon Remineralization and Iron Cycling in Relation to Sea Ice Cover along the Eastern Continental Shelf of the Antarctic Peninsula Baloza, Marwa Henkel, Susann Geibert, Walter Kasten, Sabine Holtappels, Moritz 2022-06-17 https://epic.awi.de/id/eprint/56460/ https://hdl.handle.net/10013/epic.e9c5e908-c356-4830-abf8-77fb32bb9bd2 unknown Wiley Baloza, M. orcid:0000-0002-6885-8463 , Henkel, S. orcid:0000-0001-7490-0237 , Geibert, W. orcid:0000-0001-8646-2334 , Kasten, S. orcid:0000-0001-7453-5137 and Holtappels, M. orcid:0000-0003-3682-1903 , Bentho-Pelagic Processes, Marine Geochemistry (2022) Benthic Carbon Remineralization and Iron Cycling in Relation to Sea Ice Cover along the Eastern Continental Shelf of the Antarctic Peninsula , Journal of Geophysical Research-Oceans . doi:10.1029/2021JC018401 <https://doi.org/10.1029/2021JC018401> , hdl:10013/epic.e9c5e908-c356-4830-abf8-77fb32bb9bd2 EPIC3Journal of Geophysical Research-Oceans, Wiley, ISSN: 0148-0227 Article NonPeerReviewed 2022 ftawi https://doi.org/10.1029/2021JC018401 2024-06-24T04:28:46Z Rapid and profound climatic and environmental changes have been predicted for the Antarctic Peninsula with so far unknown impact on the biogeochemistry of the continental shelves. In this study, we investigate benthic carbon sedimentation, remineralization and iron cycling using sediment cores retrieved on a 400 mile transect with contrasting sea ice conditions along the eastern shelf of the Antarctic Peninsula. Sediments at comparable water depths of 330-450 m showed sedimentation and remineralization rates of organic carbon, ranging from 2.5-13 and 1.8-7.2 mmol C m-2 d-1, respectively. Both rates were positively correlated with the occurrence of marginal sea ice conditions (5-35% ice cover) along the transect, suggesting a favorable influence of the corresponding light regime and water column stratification on algae growth and sedimentation rates. From south to north, the burial efficiency of organic carbon decreased from 58% to 27%, while bottom water temperatures increased from -1.9 to -0.1 °C. Net iron reduction rates, as estimated from pore-water profiles of dissolved iron, were significantly correlated with carbon degradation rates and contributed 0.7-1.2% to the total organic carbon remineralization. Tightly coupled phosphate-iron recycling was indicated by significant covariation of dissolved iron and phosphate concentrations, which almost consistently exhibited P/Fe flux ratios of 0.26. Iron efflux into bottom waters of 0.6-4.5 µmol Fe m-2 d-1 was estimated from an empirical model. Despite the deep shelf waters, a clear bentho-pelagic coupling is indicated, shaped by the extent and duration of marginal sea ice conditions during summer, and likely to be affected by future climate change. Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Sea ice Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Journal of Geophysical Research: Oceans 127 7 |
institution |
Open Polar |
collection |
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
Rapid and profound climatic and environmental changes have been predicted for the Antarctic Peninsula with so far unknown impact on the biogeochemistry of the continental shelves. In this study, we investigate benthic carbon sedimentation, remineralization and iron cycling using sediment cores retrieved on a 400 mile transect with contrasting sea ice conditions along the eastern shelf of the Antarctic Peninsula. Sediments at comparable water depths of 330-450 m showed sedimentation and remineralization rates of organic carbon, ranging from 2.5-13 and 1.8-7.2 mmol C m-2 d-1, respectively. Both rates were positively correlated with the occurrence of marginal sea ice conditions (5-35% ice cover) along the transect, suggesting a favorable influence of the corresponding light regime and water column stratification on algae growth and sedimentation rates. From south to north, the burial efficiency of organic carbon decreased from 58% to 27%, while bottom water temperatures increased from -1.9 to -0.1 °C. Net iron reduction rates, as estimated from pore-water profiles of dissolved iron, were significantly correlated with carbon degradation rates and contributed 0.7-1.2% to the total organic carbon remineralization. Tightly coupled phosphate-iron recycling was indicated by significant covariation of dissolved iron and phosphate concentrations, which almost consistently exhibited P/Fe flux ratios of 0.26. Iron efflux into bottom waters of 0.6-4.5 µmol Fe m-2 d-1 was estimated from an empirical model. Despite the deep shelf waters, a clear bentho-pelagic coupling is indicated, shaped by the extent and duration of marginal sea ice conditions during summer, and likely to be affected by future climate change. |
format |
Article in Journal/Newspaper |
author |
Baloza, Marwa Henkel, Susann Geibert, Walter Kasten, Sabine Holtappels, Moritz |
spellingShingle |
Baloza, Marwa Henkel, Susann Geibert, Walter Kasten, Sabine Holtappels, Moritz Benthic Carbon Remineralization and Iron Cycling in Relation to Sea Ice Cover along the Eastern Continental Shelf of the Antarctic Peninsula |
author_facet |
Baloza, Marwa Henkel, Susann Geibert, Walter Kasten, Sabine Holtappels, Moritz |
author_sort |
Baloza, Marwa |
title |
Benthic Carbon Remineralization and Iron Cycling in Relation to Sea Ice Cover along the Eastern Continental Shelf of the Antarctic Peninsula |
title_short |
Benthic Carbon Remineralization and Iron Cycling in Relation to Sea Ice Cover along the Eastern Continental Shelf of the Antarctic Peninsula |
title_full |
Benthic Carbon Remineralization and Iron Cycling in Relation to Sea Ice Cover along the Eastern Continental Shelf of the Antarctic Peninsula |
title_fullStr |
Benthic Carbon Remineralization and Iron Cycling in Relation to Sea Ice Cover along the Eastern Continental Shelf of the Antarctic Peninsula |
title_full_unstemmed |
Benthic Carbon Remineralization and Iron Cycling in Relation to Sea Ice Cover along the Eastern Continental Shelf of the Antarctic Peninsula |
title_sort |
benthic carbon remineralization and iron cycling in relation to sea ice cover along the eastern continental shelf of the antarctic peninsula |
publisher |
Wiley |
publishDate |
2022 |
url |
https://epic.awi.de/id/eprint/56460/ https://hdl.handle.net/10013/epic.e9c5e908-c356-4830-abf8-77fb32bb9bd2 |
genre |
Antarc* Antarctic Antarctic Peninsula Sea ice |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Sea ice |
op_source |
EPIC3Journal of Geophysical Research-Oceans, Wiley, ISSN: 0148-0227 |
op_relation |
Baloza, M. orcid:0000-0002-6885-8463 , Henkel, S. orcid:0000-0001-7490-0237 , Geibert, W. orcid:0000-0001-8646-2334 , Kasten, S. orcid:0000-0001-7453-5137 and Holtappels, M. orcid:0000-0003-3682-1903 , Bentho-Pelagic Processes, Marine Geochemistry (2022) Benthic Carbon Remineralization and Iron Cycling in Relation to Sea Ice Cover along the Eastern Continental Shelf of the Antarctic Peninsula , Journal of Geophysical Research-Oceans . doi:10.1029/2021JC018401 <https://doi.org/10.1029/2021JC018401> , hdl:10013/epic.e9c5e908-c356-4830-abf8-77fb32bb9bd2 |
op_doi |
https://doi.org/10.1029/2021JC018401 |
container_title |
Journal of Geophysical Research: Oceans |
container_volume |
127 |
container_issue |
7 |
_version_ |
1810493153375944704 |