Production regime and associated N cycling in the vicinity of Kerguelen Island, Southern Ocean
International audience Although the Southern Ocean is considered a high-nutrient, low-chlorophyll (HNLC) area, massive and recurrent blooms are observed over and downstream of the Kerguelen Plateau. This mosaic of blooms is triggered by a higher iron supply resulting from the interaction between the...
Published in: | Biogeosciences |
---|---|
Main Authors: | , , , , , , , , , , , , , , , |
Other Authors: | , , , , , , , , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2015
|
Subjects: | |
Online Access: | https://hal.archives-ouvertes.fr/hal-01812504 https://hal.archives-ouvertes.fr/hal-01812504/document https://hal.archives-ouvertes.fr/hal-01812504/file/Cavagna%20et%20al.,%202015.pdf https://doi.org/10.5194/bg-12-6515-2015 |
id |
ftccsdartic:oai:HAL:hal-01812504v1 |
---|---|
record_format |
openpolar |
institution |
Open Polar |
collection |
Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) |
op_collection_id |
ftccsdartic |
language |
English |
topic |
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
spellingShingle |
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography Cavagna, Anne-Julie Fripiat, François Elskens, Marc Mangion, P. Chirurgien, L. Closset, Ivia Lasbleiz, M. Florez-Leiva, L. Cardinal, Damien Leblanc, K. Fernandez, C. Lefèvre, Dominique Oriol, L. Blain, Stéphane QUEGUINER, Bernard Dehairs, Frank Production regime and associated N cycling in the vicinity of Kerguelen Island, Southern Ocean |
topic_facet |
[SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
description |
International audience Although the Southern Ocean is considered a high-nutrient, low-chlorophyll (HNLC) area, massive and recurrent blooms are observed over and downstream of the Kerguelen Plateau. This mosaic of blooms is triggered by a higher iron supply resulting from the interaction between the Antarctic Circumpolar Current and the local bathymetry. Net primary production, N uptake (NO − 3 and NH + 4 ), and nitrification rates were measured at eight stations in austral spring 2011 (October–November) during the KEOPS 2 cruise in the Kerguelen Plateau area. Natural iron fertilization stimulated primary production, with mixed layer integrated net primary production and growth rates much higher in the fertilized areas (up to 315 mmol C m −2 d −1 and up to 0.31 d −1 respectively) compared to the HNLC reference site (12 mmol C m −2 d −1 and 0.06 d −1 respectively). Primary production was mainly sustained by nitrate uptake, with f ratios (corresponding to NO − 3-uptake / (NO − 3-uptake + NH + 4-uptake)) lying at the upper end of the observations for the Southern Ocean (up to 0.9). We report high rates of nitrification (up to ∼ 3 µmol N L −1 d −1 , with ∼ 90 % of them < 1 µmol N L −1 d −1 ) typically occurring below the euphotic zone, as classically observed in the global ocean. The speci-ficity of the studied area is that at most of the stations, the euphotic layer was shallower than the mixed layer, implying that nitrifiers can efficiently compete with phytoplankton for the ammonium produced by remineralization at low-light intensities. Nitrate produced by nitrification in the mixed layer below the euphotic zone is easily supplied to the euphotic zone waters above, and nitrification sustained 70 ± 30 % of the nitrate uptake in the productive area above the Kerguelen Plateau. This complicates estimations of new production as potentially exportable production. We conclude that high productivity in deep mixing system stimulates the N cycle by increasing both assimilation and regeneration. |
author2 |
Analytical and Environmental Chemistry and Earth System Sciences Vrije Universiteit Brussel (VUB) Southern Cross University (SCU) 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)-Centre National de la Recherche Scientifique (CNRS)-Université de Toulon (UTLN) Biogéochimie-Traceurs-Paléoclimat (BTP) Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN) Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)) École normale supérieure - Paris (ENS Paris) Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris) Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)) Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS) Universidad de Antioquia = University of Antioquia Medellín, Colombia Departamento de Oceanografía Concepción Universidad de Concepción Chile Laboratoire d'Océanographie Microbienne (LOMIC) Observatoire océanologique de Banyuls (OOB) Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) KEOPS 2 |
format |
Article in Journal/Newspaper |
author |
Cavagna, Anne-Julie Fripiat, François Elskens, Marc Mangion, P. Chirurgien, L. Closset, Ivia Lasbleiz, M. Florez-Leiva, L. Cardinal, Damien Leblanc, K. Fernandez, C. Lefèvre, Dominique Oriol, L. Blain, Stéphane QUEGUINER, Bernard Dehairs, Frank |
author_facet |
Cavagna, Anne-Julie Fripiat, François Elskens, Marc Mangion, P. Chirurgien, L. Closset, Ivia Lasbleiz, M. Florez-Leiva, L. Cardinal, Damien Leblanc, K. Fernandez, C. Lefèvre, Dominique Oriol, L. Blain, Stéphane QUEGUINER, Bernard Dehairs, Frank |
author_sort |
Cavagna, Anne-Julie |
title |
Production regime and associated N cycling in the vicinity of Kerguelen Island, Southern Ocean |
title_short |
Production regime and associated N cycling in the vicinity of Kerguelen Island, Southern Ocean |
title_full |
Production regime and associated N cycling in the vicinity of Kerguelen Island, Southern Ocean |
title_fullStr |
Production regime and associated N cycling in the vicinity of Kerguelen Island, Southern Ocean |
title_full_unstemmed |
Production regime and associated N cycling in the vicinity of Kerguelen Island, Southern Ocean |
title_sort |
production regime and associated n cycling in the vicinity of kerguelen island, southern ocean |
publisher |
HAL CCSD |
publishDate |
2015 |
url |
https://hal.archives-ouvertes.fr/hal-01812504 https://hal.archives-ouvertes.fr/hal-01812504/document https://hal.archives-ouvertes.fr/hal-01812504/file/Cavagna%20et%20al.,%202015.pdf https://doi.org/10.5194/bg-12-6515-2015 |
long_lat |
ENVELOPE(69.500,69.500,-49.250,-49.250) |
geographic |
Antarctic Austral Kerguelen Kerguelen Island Southern Ocean The Antarctic |
geographic_facet |
Antarctic Austral Kerguelen Kerguelen Island Southern Ocean The Antarctic |
genre |
Antarc* Antarctic Southern Ocean |
genre_facet |
Antarc* Antarctic Southern Ocean |
op_source |
ISSN: 1726-4170 EISSN: 1726-4189 Biogeosciences https://hal.archives-ouvertes.fr/hal-01812504 Biogeosciences, European Geosciences Union, 2015, 12 (21), pp.6515-6528. ⟨10.5194/bg-12-6515-2015⟩ https://www.biogeosciences.net/12/6515/2015/bg-12-6515-2015.pdf |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/bg-12-6515-2015 hal-01812504 https://hal.archives-ouvertes.fr/hal-01812504 https://hal.archives-ouvertes.fr/hal-01812504/document https://hal.archives-ouvertes.fr/hal-01812504/file/Cavagna%20et%20al.,%202015.pdf doi:10.5194/bg-12-6515-2015 WOS: 000365091900018 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.5194/bg-12-6515-2015 |
container_title |
Biogeosciences |
container_volume |
12 |
container_issue |
21 |
container_start_page |
6515 |
op_container_end_page |
6528 |
_version_ |
1766090026054057984 |
spelling |
ftccsdartic:oai:HAL:hal-01812504v1 2023-05-15T13:37:17+02:00 Production regime and associated N cycling in the vicinity of Kerguelen Island, Southern Ocean Cavagna, Anne-Julie Fripiat, François Elskens, Marc Mangion, P. Chirurgien, L. Closset, Ivia Lasbleiz, M. Florez-Leiva, L. Cardinal, Damien Leblanc, K. Fernandez, C. Lefèvre, Dominique Oriol, L. Blain, Stéphane QUEGUINER, Bernard Dehairs, Frank Analytical and Environmental Chemistry and Earth System Sciences Vrije Universiteit Brussel (VUB) Southern Cross University (SCU) 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)-Centre National de la Recherche Scientifique (CNRS)-Université de Toulon (UTLN) Biogéochimie-Traceurs-Paléoclimat (BTP) Laboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques (LOCEAN) Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)) École normale supérieure - Paris (ENS Paris) Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-École normale supérieure - Paris (ENS Paris) Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Muséum national d'Histoire naturelle (MNHN)-Institut Pierre-Simon-Laplace (IPSL (FR_636)) Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7)-École polytechnique (X)-Centre National d'Études Spatiales Toulouse (CNES)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS) Universidad de Antioquia = University of Antioquia Medellín, Colombia Departamento de Oceanografía Concepción Universidad de Concepción Chile Laboratoire d'Océanographie Microbienne (LOMIC) Observatoire océanologique de Banyuls (OOB) Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) KEOPS 2 2015 https://hal.archives-ouvertes.fr/hal-01812504 https://hal.archives-ouvertes.fr/hal-01812504/document https://hal.archives-ouvertes.fr/hal-01812504/file/Cavagna%20et%20al.,%202015.pdf https://doi.org/10.5194/bg-12-6515-2015 en eng HAL CCSD European Geosciences Union info:eu-repo/semantics/altIdentifier/doi/10.5194/bg-12-6515-2015 hal-01812504 https://hal.archives-ouvertes.fr/hal-01812504 https://hal.archives-ouvertes.fr/hal-01812504/document https://hal.archives-ouvertes.fr/hal-01812504/file/Cavagna%20et%20al.,%202015.pdf doi:10.5194/bg-12-6515-2015 WOS: 000365091900018 info:eu-repo/semantics/OpenAccess ISSN: 1726-4170 EISSN: 1726-4189 Biogeosciences https://hal.archives-ouvertes.fr/hal-01812504 Biogeosciences, European Geosciences Union, 2015, 12 (21), pp.6515-6528. ⟨10.5194/bg-12-6515-2015⟩ https://www.biogeosciences.net/12/6515/2015/bg-12-6515-2015.pdf [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography info:eu-repo/semantics/article Journal articles 2015 ftccsdartic https://doi.org/10.5194/bg-12-6515-2015 2021-12-05T02:38:01Z International audience Although the Southern Ocean is considered a high-nutrient, low-chlorophyll (HNLC) area, massive and recurrent blooms are observed over and downstream of the Kerguelen Plateau. This mosaic of blooms is triggered by a higher iron supply resulting from the interaction between the Antarctic Circumpolar Current and the local bathymetry. Net primary production, N uptake (NO − 3 and NH + 4 ), and nitrification rates were measured at eight stations in austral spring 2011 (October–November) during the KEOPS 2 cruise in the Kerguelen Plateau area. Natural iron fertilization stimulated primary production, with mixed layer integrated net primary production and growth rates much higher in the fertilized areas (up to 315 mmol C m −2 d −1 and up to 0.31 d −1 respectively) compared to the HNLC reference site (12 mmol C m −2 d −1 and 0.06 d −1 respectively). Primary production was mainly sustained by nitrate uptake, with f ratios (corresponding to NO − 3-uptake / (NO − 3-uptake + NH + 4-uptake)) lying at the upper end of the observations for the Southern Ocean (up to 0.9). We report high rates of nitrification (up to ∼ 3 µmol N L −1 d −1 , with ∼ 90 % of them < 1 µmol N L −1 d −1 ) typically occurring below the euphotic zone, as classically observed in the global ocean. The speci-ficity of the studied area is that at most of the stations, the euphotic layer was shallower than the mixed layer, implying that nitrifiers can efficiently compete with phytoplankton for the ammonium produced by remineralization at low-light intensities. Nitrate produced by nitrification in the mixed layer below the euphotic zone is easily supplied to the euphotic zone waters above, and nitrification sustained 70 ± 30 % of the nitrate uptake in the productive area above the Kerguelen Plateau. This complicates estimations of new production as potentially exportable production. We conclude that high productivity in deep mixing system stimulates the N cycle by increasing both assimilation and regeneration. Article in Journal/Newspaper Antarc* Antarctic Southern Ocean Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) Antarctic Austral Kerguelen Kerguelen Island ENVELOPE(69.500,69.500,-49.250,-49.250) Southern Ocean The Antarctic Biogeosciences 12 21 6515 6528 |