Seasonal microbial food web dynamics in contrasting Southern Ocean productivity regimes
International audience Spatial and seasonal dynamics of microbial loop fluxes were investigated in contrasting productivity regimes in the Indian sector of the Southern Ocean. Observations carried out in late summer (February-March 2018; project MOBYDICK) revealed higher microbial biomasses and flux...
Published in: | Limnology and Oceanography |
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Main Authors: | , , , , , , , , , , , , |
Other Authors: | , , , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2020
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Subjects: | |
Online Access: | https://doi.org/10.1002/lno.11591 https://hal-univ-poitiers.archives-ouvertes.fr/hal-03034631/file/Christaki_2020_HAL.pdf https://hal-univ-poitiers.archives-ouvertes.fr/hal-03034631 |
id |
fttriple:oai:gotriple.eu:10670/1.40rj0f |
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record_format |
openpolar |
institution |
Open Polar |
collection |
Unknown |
op_collection_id |
fttriple |
language |
English |
topic |
Microbial food web fluxes Southern Ocean productivity regimes acl envir geo |
spellingShingle |
Microbial food web fluxes Southern Ocean productivity regimes acl envir geo Chistaki, Urania Guenegues, Audrey Liu, Yan Blain, Stéphane Catala, Philippe Colombet, Jonathan Debeljak, Pavla Jardillier, Ludwig Irion, Solène Planchon, Frédéric Sassenhagen, Ingrid Sime-Ngando, Télesphore Obernosterer, Ingrid Seasonal microbial food web dynamics in contrasting Southern Ocean productivity regimes |
topic_facet |
Microbial food web fluxes Southern Ocean productivity regimes acl envir geo |
description |
International audience Spatial and seasonal dynamics of microbial loop fluxes were investigated in contrasting productivity regimes in the Indian sector of the Southern Ocean. Observations carried out in late summer (February-March 2018; project MOBYDICK) revealed higher microbial biomasses and fluxes in the naturally iron-fertilized surface waters of Kerguelen island in comparison to surrounding off-plateau waters. Differences were most pronounced for bacterial heterotrophic production (2.3-fold), the abundance of heterotrophic nanoflagellates (HNF; 2.7-fold). Independent of site, grazing by HNF was the main loss process of bacterial production (80-100%), while virus-induced mortality was low (< 9%). Combining these results with observations from previous investigations during early spring and summer allowed us to describe seasonal patterns in microbial food web fluxes and to compare these to carbon export in the iron-fertilized and highnutrient, low-chlorophyll (HNLC) Southern Ocean. Our data suggest an overall less efficient microbial food web during spring and summer, when respiration and viral lysis, respectively, represent important loss terms of bacterially-mediated carbon. In late summer, primary production is more efficiently transferred to bacterial biomass and HNF and thus available for higher trophic levels. These results provide a new insight into the seasonal variability and the quantitative importance of microbial food web processes for the fate of primary production in the Southern Ocean. |
author2 |
Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 (LOG) Centre National de la Recherche Scientifique (CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Institut national des sciences de l'Univers (INSU - CNRS) Laboratoire d'Océanographie Microbienne (LOMIC) Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire océanologique de Banyuls (OOB) Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) Laboratoire Microorganismes : Génome et Environnement (LMGE) Université Clermont Auvergne 2017-2020 (UCA 2017-2020 )-Centre National de la Recherche Scientifique (CNRS) Ecologie Systématique et Evolution (ESE) AgroParisTech-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR) 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)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université de Brest (UBO) We thank B. Queguiner, the PI of the MOBYDICK project, for providing us the opportunity to participate to this cruise, the captain and crew of the R/V Marion Dufresne for their enthusiasm and support aboard during the MOBYDICK-THEMISTO cruise (https://doi.org/10.17600/18000403) and the chief scientist I. Obernosterer. This work was supported by the French oceanographic fleet ("Flotte oceanographique francaise"), the French ANR ("Agence Nationale de la Recherche", AAPG 2017 program, MOBYDICK Project number: ANR-17-CE01-0013), and the French Research program of INSU-CNRS LEFE/CYBER ("Les enveloppes fluides et l'environnement"-"Cycles biogeochimiques, environnement et ressources"). This work was also supported by ULCO (Universite du Littoral) and CPER MARCO (https://marco.univ-littoral.fr/).We thank three anonymous reviewers and the editors for their comments which helped to improve this work. ANR-17-CE01-0013,MOBYDICK,Biodiversité des Ecosystèmes Marins et Dynamique du Carbone dans le secteur de Kerguelen : approche intégrée(2017) |
format |
Article in Journal/Newspaper |
author |
Chistaki, Urania Guenegues, Audrey Liu, Yan Blain, Stéphane Catala, Philippe Colombet, Jonathan Debeljak, Pavla Jardillier, Ludwig Irion, Solène Planchon, Frédéric Sassenhagen, Ingrid Sime-Ngando, Télesphore Obernosterer, Ingrid |
author_facet |
Chistaki, Urania Guenegues, Audrey Liu, Yan Blain, Stéphane Catala, Philippe Colombet, Jonathan Debeljak, Pavla Jardillier, Ludwig Irion, Solène Planchon, Frédéric Sassenhagen, Ingrid Sime-Ngando, Télesphore Obernosterer, Ingrid |
author_sort |
Chistaki, Urania |
title |
Seasonal microbial food web dynamics in contrasting Southern Ocean productivity regimes |
title_short |
Seasonal microbial food web dynamics in contrasting Southern Ocean productivity regimes |
title_full |
Seasonal microbial food web dynamics in contrasting Southern Ocean productivity regimes |
title_fullStr |
Seasonal microbial food web dynamics in contrasting Southern Ocean productivity regimes |
title_full_unstemmed |
Seasonal microbial food web dynamics in contrasting Southern Ocean productivity regimes |
title_sort |
seasonal microbial food web dynamics in contrasting southern ocean productivity regimes |
publisher |
HAL CCSD |
publishDate |
2020 |
url |
https://doi.org/10.1002/lno.11591 https://hal-univ-poitiers.archives-ouvertes.fr/hal-03034631/file/Christaki_2020_HAL.pdf https://hal-univ-poitiers.archives-ouvertes.fr/hal-03034631 |
long_lat |
ENVELOPE(69.500,69.500,-49.250,-49.250) |
geographic |
Indian Kerguelen Kerguelen Island Southern Ocean |
geographic_facet |
Indian Kerguelen Kerguelen Island Southern Ocean |
genre |
Southern Ocean |
genre_facet |
Southern Ocean |
op_source |
Hyper Article en Ligne - Sciences de l'Homme et de la Société ISSN: 0024-3590 EISSN: 1939-5590 Limnology and Oceanography Limnology and Oceanography, Association for the Sciences of Limnology and Oceanography, 2020, ⟨10.1002/lno.11591⟩ |
op_relation |
hal-03034631 doi:10.1002/lno.11591 WOS: 000569169700001 10670/1.40rj0f https://hal-univ-poitiers.archives-ouvertes.fr/hal-03034631/file/Christaki_2020_HAL.pdf https://hal-univ-poitiers.archives-ouvertes.fr/hal-03034631 |
op_doi |
https://doi.org/10.1002/lno.11591 |
container_title |
Limnology and Oceanography |
container_volume |
66 |
container_issue |
1 |
container_start_page |
108 |
op_container_end_page |
122 |
_version_ |
1766204519868268544 |
spelling |
fttriple:oai:gotriple.eu:10670/1.40rj0f 2023-05-15T18:24:11+02:00 Seasonal microbial food web dynamics in contrasting Southern Ocean productivity regimes Chistaki, Urania Guenegues, Audrey Liu, Yan Blain, Stéphane Catala, Philippe Colombet, Jonathan Debeljak, Pavla Jardillier, Ludwig Irion, Solène Planchon, Frédéric Sassenhagen, Ingrid Sime-Ngando, Télesphore Obernosterer, Ingrid Laboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 (LOG) Centre National de la Recherche Scientifique (CNRS)-Université du Littoral Côte d'Opale (ULCO)-Université de Lille-Institut national des sciences de l'Univers (INSU - CNRS) Laboratoire d'Océanographie Microbienne (LOMIC) Centre National de la Recherche Scientifique (CNRS)-Sorbonne Université (SU)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire océanologique de Banyuls (OOB) Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) Laboratoire Microorganismes : Génome et Environnement (LMGE) Université Clermont Auvergne 2017-2020 (UCA 2017-2020 )-Centre National de la Recherche Scientifique (CNRS) Ecologie Systématique et Evolution (ESE) AgroParisTech-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS) Laboratoire des Sciences de l'Environnement Marin (LEMAR) (LEMAR) 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)-Institut Français de Recherche pour l'Exploitation de la Mer (IFREMER)-Centre National de la Recherche Scientifique (CNRS)-Université de Brest (UBO) We thank B. Queguiner, the PI of the MOBYDICK project, for providing us the opportunity to participate to this cruise, the captain and crew of the R/V Marion Dufresne for their enthusiasm and support aboard during the MOBYDICK-THEMISTO cruise (https://doi.org/10.17600/18000403) and the chief scientist I. Obernosterer. This work was supported by the French oceanographic fleet ("Flotte oceanographique francaise"), the French ANR ("Agence Nationale de la Recherche", AAPG 2017 program, MOBYDICK Project number: ANR-17-CE01-0013), and the French Research program of INSU-CNRS LEFE/CYBER ("Les enveloppes fluides et l'environnement"-"Cycles biogeochimiques, environnement et ressources"). This work was also supported by ULCO (Universite du Littoral) and CPER MARCO (https://marco.univ-littoral.fr/).We thank three anonymous reviewers and the editors for their comments which helped to improve this work. ANR-17-CE01-0013,MOBYDICK,Biodiversité des Ecosystèmes Marins et Dynamique du Carbone dans le secteur de Kerguelen : approche intégrée(2017) 2020-09-15 https://doi.org/10.1002/lno.11591 https://hal-univ-poitiers.archives-ouvertes.fr/hal-03034631/file/Christaki_2020_HAL.pdf https://hal-univ-poitiers.archives-ouvertes.fr/hal-03034631 en eng HAL CCSD Association for the Sciences of Limnology and Oceanography hal-03034631 doi:10.1002/lno.11591 WOS: 000569169700001 10670/1.40rj0f https://hal-univ-poitiers.archives-ouvertes.fr/hal-03034631/file/Christaki_2020_HAL.pdf https://hal-univ-poitiers.archives-ouvertes.fr/hal-03034631 Hyper Article en Ligne - Sciences de l'Homme et de la Société ISSN: 0024-3590 EISSN: 1939-5590 Limnology and Oceanography Limnology and Oceanography, Association for the Sciences of Limnology and Oceanography, 2020, ⟨10.1002/lno.11591⟩ Microbial food web fluxes Southern Ocean productivity regimes acl envir geo Journal Article https://vocabularies.coar-repositories.org/resource_types/c_6501/ 2020 fttriple https://doi.org/10.1002/lno.11591 2023-01-22T17:08:52Z International audience Spatial and seasonal dynamics of microbial loop fluxes were investigated in contrasting productivity regimes in the Indian sector of the Southern Ocean. Observations carried out in late summer (February-March 2018; project MOBYDICK) revealed higher microbial biomasses and fluxes in the naturally iron-fertilized surface waters of Kerguelen island in comparison to surrounding off-plateau waters. Differences were most pronounced for bacterial heterotrophic production (2.3-fold), the abundance of heterotrophic nanoflagellates (HNF; 2.7-fold). Independent of site, grazing by HNF was the main loss process of bacterial production (80-100%), while virus-induced mortality was low (< 9%). Combining these results with observations from previous investigations during early spring and summer allowed us to describe seasonal patterns in microbial food web fluxes and to compare these to carbon export in the iron-fertilized and highnutrient, low-chlorophyll (HNLC) Southern Ocean. Our data suggest an overall less efficient microbial food web during spring and summer, when respiration and viral lysis, respectively, represent important loss terms of bacterially-mediated carbon. In late summer, primary production is more efficiently transferred to bacterial biomass and HNF and thus available for higher trophic levels. These results provide a new insight into the seasonal variability and the quantitative importance of microbial food web processes for the fate of primary production in the Southern Ocean. Article in Journal/Newspaper Southern Ocean Unknown Indian Kerguelen Kerguelen Island ENVELOPE(69.500,69.500,-49.250,-49.250) Southern Ocean Limnology and Oceanography 66 1 108 122 |