Significant mixed layer nitrification in a natural iron-fertilized bloom of the Southern Ocean
WOS:000368907500005 International audience Nitrification, the microbially mediated oxidation of ammonium into nitrate, is generally expected to be low in the Southern Ocean mixed layer. This paradigm assumes that nitrate is mainly provided through vertical mixing and assimilated during the vegetativ...
Published in: | Global Biogeochemical Cycles |
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Main Authors: | , , , , , , , , , , |
Other Authors: | , , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2015
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Subjects: | |
Online Access: | https://hal.science/hal-02556217 https://hal.science/hal-02556217/document https://hal.science/hal-02556217/file/2014GB005051.pdf https://doi.org/10.1002/2014GB005051 |
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ftunivbrest:oai:HAL:hal-02556217v1 |
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record_format |
openpolar |
institution |
Open Polar |
collection |
Université de Bretagne Occidentale: HAL |
op_collection_id |
ftunivbrest |
language |
English |
topic |
organic-carbon north pacific ACL stable-isotopes fresh-water biogenic silica kerguelen plateau nitrous-oxide production oxygen isotopic composition phytoplankton bloom sea-ice [SDE.BE]Environmental Sciences/Biodiversity and Ecology [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere |
spellingShingle |
organic-carbon north pacific ACL stable-isotopes fresh-water biogenic silica kerguelen plateau nitrous-oxide production oxygen isotopic composition phytoplankton bloom sea-ice [SDE.BE]Environmental Sciences/Biodiversity and Ecology [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere Fripiat, F. Elskens, M. Trull, T. W. Blain, S. Cavagna, A.-J. Fernandez, C. Fonseca-Batista, D. Planchon, F. Raimbault, Patrick Roukaerts, A. Dehairs, F. Significant mixed layer nitrification in a natural iron-fertilized bloom of the Southern Ocean |
topic_facet |
organic-carbon north pacific ACL stable-isotopes fresh-water biogenic silica kerguelen plateau nitrous-oxide production oxygen isotopic composition phytoplankton bloom sea-ice [SDE.BE]Environmental Sciences/Biodiversity and Ecology [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere |
description |
WOS:000368907500005 International audience Nitrification, the microbially mediated oxidation of ammonium into nitrate, is generally expected to be low in the Southern Ocean mixed layer. This paradigm assumes that nitrate is mainly provided through vertical mixing and assimilated during the vegetative season, supporting the concept that nitrate uptake is equivalent to the new primary production (i.e., primary production which is potentially available for export). Here we show that nitrification is significant (similar to 40-80% of the seasonal nitrate uptake) in the naturally iron-fertilized bloom over the southeast Kerguelen Plateau. Hence, a large fraction of the nitrate-based primary production is regenerated, instead of being exported. It appears that nitrate assimilation (light dependent) and nitrification (partly light inhibited) are spatially separated between the upper and lower parts, respectively, of the deep surface mixed layers. These deep mixed layers, extending well below the euphotic layer, allow nitrifiers to compete with phytoplankton for the assimilation of ammonium. The high contributions of nitrification to nitrate uptake are in agreement with both low export efficiency (i.e., the percentage of primary production that is exported) and low seasonal nitrate drawdown despite high nitrate assimilation. |
author2 |
Analytical, Environmental and Geo- Chemistry Vrije Universiteit Brussel (VUB) CSIRO Marine and Atmospheric Research (CSIRO-MAR) Commonwealth Scientific and Industrial Research Organisation Canberra (CSIRO) Antarctic Climate and Ecosystems Cooperative Research Centre (ACE-CRC) Laboratoire d'Océanographie Microbienne (LOMIC) Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Observatoire océanologique de Banyuls (OOB) Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR) Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM) Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) Institut méditerranéen d'océanologie (MIO) Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Fripiat, F. Elskens, M. Trull, T. W. Blain, S. Cavagna, A.-J. Fernandez, C. Fonseca-Batista, D. Planchon, F. Raimbault, Patrick Roukaerts, A. Dehairs, F. |
author_facet |
Fripiat, F. Elskens, M. Trull, T. W. Blain, S. Cavagna, A.-J. Fernandez, C. Fonseca-Batista, D. Planchon, F. Raimbault, Patrick Roukaerts, A. Dehairs, F. |
author_sort |
Fripiat, F. |
title |
Significant mixed layer nitrification in a natural iron-fertilized bloom of the Southern Ocean |
title_short |
Significant mixed layer nitrification in a natural iron-fertilized bloom of the Southern Ocean |
title_full |
Significant mixed layer nitrification in a natural iron-fertilized bloom of the Southern Ocean |
title_fullStr |
Significant mixed layer nitrification in a natural iron-fertilized bloom of the Southern Ocean |
title_full_unstemmed |
Significant mixed layer nitrification in a natural iron-fertilized bloom of the Southern Ocean |
title_sort |
significant mixed layer nitrification in a natural iron-fertilized bloom of the southern ocean |
publisher |
HAL CCSD |
publishDate |
2015 |
url |
https://hal.science/hal-02556217 https://hal.science/hal-02556217/document https://hal.science/hal-02556217/file/2014GB005051.pdf https://doi.org/10.1002/2014GB005051 |
geographic |
Southern Ocean Kerguelen Pacific |
geographic_facet |
Southern Ocean Kerguelen Pacific |
genre |
Sea ice Southern Ocean |
genre_facet |
Sea ice Southern Ocean |
op_source |
ISSN: 0886-6236 EISSN: 1944-8224 Global Biogeochemical Cycles https://hal.science/hal-02556217 Global Biogeochemical Cycles, 2015, 29 (11), pp.1929-1943. ⟨10.1002/2014GB005051⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1002/2014GB005051 hal-02556217 https://hal.science/hal-02556217 https://hal.science/hal-02556217/document https://hal.science/hal-02556217/file/2014GB005051.pdf doi:10.1002/2014GB005051 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1002/2014GB005051 |
container_title |
Global Biogeochemical Cycles |
container_volume |
29 |
container_issue |
11 |
container_start_page |
1929 |
op_container_end_page |
1943 |
_version_ |
1798854460956475392 |
spelling |
ftunivbrest:oai:HAL:hal-02556217v1 2024-05-12T08:10:55+00:00 Significant mixed layer nitrification in a natural iron-fertilized bloom of the Southern Ocean Fripiat, F. Elskens, M. Trull, T. W. Blain, S. Cavagna, A.-J. Fernandez, C. Fonseca-Batista, D. Planchon, F. Raimbault, Patrick Roukaerts, A. Dehairs, F. Analytical, Environmental and Geo- Chemistry Vrije Universiteit Brussel (VUB) CSIRO Marine and Atmospheric Research (CSIRO-MAR) Commonwealth Scientific and Industrial Research Organisation Canberra (CSIRO) Antarctic Climate and Ecosystems Cooperative Research Centre (ACE-CRC) Laboratoire d'Océanographie Microbienne (LOMIC) Institut national des sciences de l'Univers (INSU - CNRS)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Observatoire océanologique de Banyuls (OOB) Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR) Institut de Recherche pour le Développement (IRD)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Université de Brest (UBO)-Institut Universitaire Européen de la Mer (IUEM) Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Brest (UBO)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) Institut méditerranéen d'océanologie (MIO) Institut de Recherche pour le Développement (IRD)-Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Université de Toulon (UTLN)-Centre National de la Recherche Scientifique (CNRS) 2015 https://hal.science/hal-02556217 https://hal.science/hal-02556217/document https://hal.science/hal-02556217/file/2014GB005051.pdf https://doi.org/10.1002/2014GB005051 en eng HAL CCSD American Geophysical Union info:eu-repo/semantics/altIdentifier/doi/10.1002/2014GB005051 hal-02556217 https://hal.science/hal-02556217 https://hal.science/hal-02556217/document https://hal.science/hal-02556217/file/2014GB005051.pdf doi:10.1002/2014GB005051 info:eu-repo/semantics/OpenAccess ISSN: 0886-6236 EISSN: 1944-8224 Global Biogeochemical Cycles https://hal.science/hal-02556217 Global Biogeochemical Cycles, 2015, 29 (11), pp.1929-1943. ⟨10.1002/2014GB005051⟩ organic-carbon north pacific ACL stable-isotopes fresh-water biogenic silica kerguelen plateau nitrous-oxide production oxygen isotopic composition phytoplankton bloom sea-ice [SDE.BE]Environmental Sciences/Biodiversity and Ecology [SDU.OCEAN]Sciences of the Universe [physics]/Ocean Atmosphere info:eu-repo/semantics/article Journal articles 2015 ftunivbrest https://doi.org/10.1002/2014GB005051 2024-04-17T23:53:48Z WOS:000368907500005 International audience Nitrification, the microbially mediated oxidation of ammonium into nitrate, is generally expected to be low in the Southern Ocean mixed layer. This paradigm assumes that nitrate is mainly provided through vertical mixing and assimilated during the vegetative season, supporting the concept that nitrate uptake is equivalent to the new primary production (i.e., primary production which is potentially available for export). Here we show that nitrification is significant (similar to 40-80% of the seasonal nitrate uptake) in the naturally iron-fertilized bloom over the southeast Kerguelen Plateau. Hence, a large fraction of the nitrate-based primary production is regenerated, instead of being exported. It appears that nitrate assimilation (light dependent) and nitrification (partly light inhibited) are spatially separated between the upper and lower parts, respectively, of the deep surface mixed layers. These deep mixed layers, extending well below the euphotic layer, allow nitrifiers to compete with phytoplankton for the assimilation of ammonium. The high contributions of nitrification to nitrate uptake are in agreement with both low export efficiency (i.e., the percentage of primary production that is exported) and low seasonal nitrate drawdown despite high nitrate assimilation. Article in Journal/Newspaper Sea ice Southern Ocean Université de Bretagne Occidentale: HAL Southern Ocean Kerguelen Pacific Global Biogeochemical Cycles 29 11 1929 1943 |