Southern Ocean Phytoplankton Community Structure as a Gatekeeper for Global Nutrient Biogeochemistry
Upwelling and the biological pump in the Southern Ocean control the amount and stoichiometry of nutrients available for lateral export to lower latitudes, thereby collectively acting as a gatekeeper for the global thermocline nutrient distribution and global ocean productivity. Yet, the exact role p...
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ftethz:oai:www.research-collection.ethz.ch:20.500.11850/504117 2023-05-15T14:03:33+02:00 Southern Ocean Phytoplankton Community Structure as a Gatekeeper for Global Nutrient Biogeochemistry Nissen, Cara Gruber, Nicolas Münnich, Matthias Vogt, Meike 2021-08 application/application/pdf https://hdl.handle.net/20.500.11850/504117 https://doi.org/10.3929/ethz-b-000504117 en eng Wiley info:eu-repo/semantics/altIdentifier/doi/10.1029/2021GB006991 info:eu-repo/semantics/altIdentifier/wos/000690773700007 info:eu-repo/grantAgreement/SNF/Projektförderung in Mathematik, Natur- und Ingenieurwissenschaften (Abteilung II)/153452 http://hdl.handle.net/20.500.11850/504117 doi:10.3929/ethz-b-000504117 info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-nd/4.0/ Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International CC-BY-NC-ND Global Biogeochemical Cycles, 35 (8) Southern Ocean silicic acid nitrate phytoplankton diatoms coccolithophores info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion 2021 ftethz https://doi.org/20.500.11850/504117 https://doi.org/10.3929/ethz-b-000504117 https://doi.org/10.1029/2021GB006991 2022-04-25T14:33:31Z Upwelling and the biological pump in the Southern Ocean control the amount and stoichiometry of nutrients available for lateral export to lower latitudes, thereby collectively acting as a gatekeeper for the global thermocline nutrient distribution and global ocean productivity. Yet, the exact role played by phytoplankton and its community composition in this gatekeeping has not been well established. Here, we investigate this role using a high-resolution model of the Southern Ocean (ROMS-BEC) with an explicit parametrization of silicifying diatoms and calcifying coccolithophores. Consistent with expectations, diatoms are very efficient in consuming the upwelled Si (Formula presented.) south of the Antarctic Polar Front, and exporting it to depth at a rate of 91 Tmol Si (Formula presented.). This leads to Si (Formula presented.) being trapped in the Southern Ocean, preventing it from leaking laterally into the Subantarctic. Model experiments reveal that this trapping is driven by both high Si-to-N diatom uptake ratios and the relatively slow dissolution of the exported opal, with the latter being the dominant mechanism. The low (Formula presented.) consumption resulting from this high uptake ratio allows a good fraction of the upwelled (Formula presented.) to reach the Subantarctic where it fuels the growth of a mixed community including coccolithophores. Coccolithophore production and export of calcite at a rate of 0.16 Pg C (Formula presented.) facilitates an efficient transfer of the exported organic matter to depth, thereby further modifying the laterally exported nutrient levels and stoichiometry. Our results thus demonstrate a key role of phytoplankton community structure in controlling the Southern Ocean biogeochemical gate. ISSN:0886-6236 ISSN:1944-9224 Article in Journal/Newspaper Antarc* Antarctic Southern Ocean ETH Zürich Research Collection Antarctic Southern Ocean The Antarctic |
institution |
Open Polar |
collection |
ETH Zürich Research Collection |
op_collection_id |
ftethz |
language |
English |
topic |
Southern Ocean silicic acid nitrate phytoplankton diatoms coccolithophores |
spellingShingle |
Southern Ocean silicic acid nitrate phytoplankton diatoms coccolithophores Nissen, Cara Gruber, Nicolas Münnich, Matthias Vogt, Meike Southern Ocean Phytoplankton Community Structure as a Gatekeeper for Global Nutrient Biogeochemistry |
topic_facet |
Southern Ocean silicic acid nitrate phytoplankton diatoms coccolithophores |
description |
Upwelling and the biological pump in the Southern Ocean control the amount and stoichiometry of nutrients available for lateral export to lower latitudes, thereby collectively acting as a gatekeeper for the global thermocline nutrient distribution and global ocean productivity. Yet, the exact role played by phytoplankton and its community composition in this gatekeeping has not been well established. Here, we investigate this role using a high-resolution model of the Southern Ocean (ROMS-BEC) with an explicit parametrization of silicifying diatoms and calcifying coccolithophores. Consistent with expectations, diatoms are very efficient in consuming the upwelled Si (Formula presented.) south of the Antarctic Polar Front, and exporting it to depth at a rate of 91 Tmol Si (Formula presented.). This leads to Si (Formula presented.) being trapped in the Southern Ocean, preventing it from leaking laterally into the Subantarctic. Model experiments reveal that this trapping is driven by both high Si-to-N diatom uptake ratios and the relatively slow dissolution of the exported opal, with the latter being the dominant mechanism. The low (Formula presented.) consumption resulting from this high uptake ratio allows a good fraction of the upwelled (Formula presented.) to reach the Subantarctic where it fuels the growth of a mixed community including coccolithophores. Coccolithophore production and export of calcite at a rate of 0.16 Pg C (Formula presented.) facilitates an efficient transfer of the exported organic matter to depth, thereby further modifying the laterally exported nutrient levels and stoichiometry. Our results thus demonstrate a key role of phytoplankton community structure in controlling the Southern Ocean biogeochemical gate. ISSN:0886-6236 ISSN:1944-9224 |
format |
Article in Journal/Newspaper |
author |
Nissen, Cara Gruber, Nicolas Münnich, Matthias Vogt, Meike |
author_facet |
Nissen, Cara Gruber, Nicolas Münnich, Matthias Vogt, Meike |
author_sort |
Nissen, Cara |
title |
Southern Ocean Phytoplankton Community Structure as a Gatekeeper for Global Nutrient Biogeochemistry |
title_short |
Southern Ocean Phytoplankton Community Structure as a Gatekeeper for Global Nutrient Biogeochemistry |
title_full |
Southern Ocean Phytoplankton Community Structure as a Gatekeeper for Global Nutrient Biogeochemistry |
title_fullStr |
Southern Ocean Phytoplankton Community Structure as a Gatekeeper for Global Nutrient Biogeochemistry |
title_full_unstemmed |
Southern Ocean Phytoplankton Community Structure as a Gatekeeper for Global Nutrient Biogeochemistry |
title_sort |
southern ocean phytoplankton community structure as a gatekeeper for global nutrient biogeochemistry |
publisher |
Wiley |
publishDate |
2021 |
url |
https://hdl.handle.net/20.500.11850/504117 https://doi.org/10.3929/ethz-b-000504117 |
geographic |
Antarctic Southern Ocean The Antarctic |
geographic_facet |
Antarctic Southern Ocean The Antarctic |
genre |
Antarc* Antarctic Southern Ocean |
genre_facet |
Antarc* Antarctic Southern Ocean |
op_source |
Global Biogeochemical Cycles, 35 (8) |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1029/2021GB006991 info:eu-repo/semantics/altIdentifier/wos/000690773700007 info:eu-repo/grantAgreement/SNF/Projektförderung in Mathematik, Natur- und Ingenieurwissenschaften (Abteilung II)/153452 http://hdl.handle.net/20.500.11850/504117 doi:10.3929/ethz-b-000504117 |
op_rights |
info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-nd/4.0/ Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International |
op_rightsnorm |
CC-BY-NC-ND |
op_doi |
https://doi.org/20.500.11850/504117 https://doi.org/10.3929/ethz-b-000504117 https://doi.org/10.1029/2021GB006991 |
_version_ |
1766274241203798016 |