Seasonal microbial food web dynamics in contrasting Southern Ocean productivity regimes
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 ir...
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Format: | Article in Journal/Newspaper |
Language: | English |
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Univ. Littoral Côte d'Opale ULCO, CNRS, Univ. Lille, UMR 8187, LOG, Laboratoire d'Océanologie et de Géosciences, F‐Code postal Ville, France
2020
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Online Access: | http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-427730 https://doi.org/10.1002/lno.11591 |
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ftuppsalauniv:oai:DiVA.org:uu-427730 2023-05-15T18:24:25+02:00 Seasonal microbial food web dynamics in contrasting Southern Ocean productivity regimes Christaki, Urania Gueneugues, Audrey Liu, Yan Blain, Stéphane Catala, Philippe Colombet, Jonathan Debeljak, Pavla Jardillier, Ludwig Irion, Solène Planchon, Fred Sassenhagen, Ingrid Sime-Ngando, Telesphore Obernosterer, Ingrid 2020 application/pdf http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-427730 https://doi.org/10.1002/lno.11591 eng eng Univ. Littoral Côte d'Opale ULCO, CNRS, Univ. Lille, UMR 8187, LOG, Laboratoire d'Océanologie et de Géosciences, F‐Code postal Ville, France Sorbonne Université, CNRS, Laboratoire d'Océanographie Microbienne (LOMIC), Banyuls‐sur‐Mer, France Unité d'Ecologie, Systématique et Evolution, Université Paris‐Sud, CNRS, AgroParisTech, Université Paris‐Saclay, Orsay Cedex, France University of Brest, Laboratoire des Sciences de l'Environnement (LEMAR), UMR6539 CNRS/UBO/IFREMER/IRD, Technopôle Brest Iroise, Plouzané, France Laboratoire Microorganismes: Génome et Environnement (LMGE), UMR CNRS 6023, Clermont Université Blaise Pascal, Aubière Cedex, France Limnology and Oceanography, 0024-3590, 2020 http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-427730 doi:10.1002/lno.11591 ISI:000569169700001 info:eu-repo/semantics/openAccess Ecology Ekologi Article in journal info:eu-repo/semantics/article text 2020 ftuppsalauniv https://doi.org/10.1002/lno.11591 2023-02-23T21:54:19Z 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 high-nutrient, 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 Uppsala University: Publications (DiVA) Indian Kerguelen Kerguelen Island ENVELOPE(69.500,69.500,-49.250,-49.250) Southern Ocean Limnology and Oceanography 66 1 108 122 |
institution |
Open Polar |
collection |
Uppsala University: Publications (DiVA) |
op_collection_id |
ftuppsalauniv |
language |
English |
topic |
Ecology Ekologi |
spellingShingle |
Ecology Ekologi Christaki, Urania Gueneugues, Audrey Liu, Yan Blain, Stéphane Catala, Philippe Colombet, Jonathan Debeljak, Pavla Jardillier, Ludwig Irion, Solène Planchon, Fred Sassenhagen, Ingrid Sime-Ngando, Telesphore Obernosterer, Ingrid Seasonal microbial food web dynamics in contrasting Southern Ocean productivity regimes |
topic_facet |
Ecology Ekologi |
description |
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 high-nutrient, 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. |
format |
Article in Journal/Newspaper |
author |
Christaki, Urania Gueneugues, Audrey Liu, Yan Blain, Stéphane Catala, Philippe Colombet, Jonathan Debeljak, Pavla Jardillier, Ludwig Irion, Solène Planchon, Fred Sassenhagen, Ingrid Sime-Ngando, Telesphore Obernosterer, Ingrid |
author_facet |
Christaki, Urania Gueneugues, Audrey Liu, Yan Blain, Stéphane Catala, Philippe Colombet, Jonathan Debeljak, Pavla Jardillier, Ludwig Irion, Solène Planchon, Fred Sassenhagen, Ingrid Sime-Ngando, Telesphore Obernosterer, Ingrid |
author_sort |
Christaki, 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 |
Univ. Littoral Côte d'Opale ULCO, CNRS, Univ. Lille, UMR 8187, LOG, Laboratoire d'Océanologie et de Géosciences, F‐Code postal Ville, France |
publishDate |
2020 |
url |
http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-427730 https://doi.org/10.1002/lno.11591 |
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_relation |
Limnology and Oceanography, 0024-3590, 2020 http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-427730 doi:10.1002/lno.11591 ISI:000569169700001 |
op_rights |
info:eu-repo/semantics/openAccess |
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_ |
1766204920872042496 |