Export fluxes in a naturally iron-fertilized area of the Southern Ocean – Part 2: Importance of diatom resting spores and faecal pellets for export
International audience The biological composition of the material exported to a moored sediment trap located under the winter mixed layer of the naturally fertilized Kerguelen Plateau in the Southern Ocean was studied over an annual cycle. Despite iron availability in spring, the annual particulate...
Published in: | Biogeosciences |
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Main Authors: | , , , , |
Other Authors: | , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
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HAL CCSD
2015
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Online Access: | https://hal.sorbonne-universite.fr/hal-01207695 https://hal.sorbonne-universite.fr/hal-01207695/document https://hal.sorbonne-universite.fr/hal-01207695/file/bg-12-3171-2015.pdf https://doi.org/10.5194/bg-12-3171-2015 |
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Open Polar |
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Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) |
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ftccsdartic |
language |
English |
topic |
[SDE]Environmental Sciences |
spellingShingle |
[SDE]Environmental Sciences Rembauville, M. Blain, S. Armand, L. QUEGUINER, Bernard Salter, I. Export fluxes in a naturally iron-fertilized area of the Southern Ocean – Part 2: Importance of diatom resting spores and faecal pellets for export |
topic_facet |
[SDE]Environmental Sciences |
description |
International audience The biological composition of the material exported to a moored sediment trap located under the winter mixed layer of the naturally fertilized Kerguelen Plateau in the Southern Ocean was studied over an annual cycle. Despite iron availability in spring, the annual particulate organic carbon (POC) export (98.2 mmol m−2) at 289 m was low, but annual biogenic silica export was significant (114 mmol m−2). This feature was related to the abundance of empty diatom cells and the ratio of full to empty cells exerted a first-order control in BSi : POC export stoichiometry of the biological pump. Chaetoceros Hyalochaete spp. and Thalassiosira antarctica resting spores were responsible for more than 60% of the annual POC flux that occurred during two very short export events of < 14 days in spring–summer. Relatively low diatom fluxes were observed over the remainder of the year. Faecal pellet contribution to annual carbon flux was lower (34%) and reached its seasonal maximum in autumn and winter (> 80%). The seasonal progression of faecal pellet types revealed a clear transition from small spherical shapes (small copepods) in spring, to larger cylindrical and ellipsoid shapes in summer (euphausiids and large copepods) and finally to large tabular shapes (salps) in autumn and winter. We propose in this high-biomass, low-export (HBLE) environment that small but highly silicified and fast-sinking resting spores are able to bypass the intense grazing pressure and efficient carbon transfer to higher trophic levels that are responsible for the low fluxes observed the during the remainder of the year. More generally our study also provides a statistical framework linking the ecological succession of diatom and zooplankton communities to the seasonality of carbon and silicon export within an iron-fertilized bloom region in the Southern Ocean. |
author2 |
Laboratoire d'Océanographie Microbienne (LOMIC) Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Observatoire océanologique de Banyuls (OOB) Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) Department of Biological Sciences and Climate Futures - Macquarie University 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) Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI) |
format |
Article in Journal/Newspaper |
author |
Rembauville, M. Blain, S. Armand, L. QUEGUINER, Bernard Salter, I. |
author_facet |
Rembauville, M. Blain, S. Armand, L. QUEGUINER, Bernard Salter, I. |
author_sort |
Rembauville, M. |
title |
Export fluxes in a naturally iron-fertilized area of the Southern Ocean – Part 2: Importance of diatom resting spores and faecal pellets for export |
title_short |
Export fluxes in a naturally iron-fertilized area of the Southern Ocean – Part 2: Importance of diatom resting spores and faecal pellets for export |
title_full |
Export fluxes in a naturally iron-fertilized area of the Southern Ocean – Part 2: Importance of diatom resting spores and faecal pellets for export |
title_fullStr |
Export fluxes in a naturally iron-fertilized area of the Southern Ocean – Part 2: Importance of diatom resting spores and faecal pellets for export |
title_full_unstemmed |
Export fluxes in a naturally iron-fertilized area of the Southern Ocean – Part 2: Importance of diatom resting spores and faecal pellets for export |
title_sort |
export fluxes in a naturally iron-fertilized area of the southern ocean – part 2: importance of diatom resting spores and faecal pellets for export |
publisher |
HAL CCSD |
publishDate |
2015 |
url |
https://hal.sorbonne-universite.fr/hal-01207695 https://hal.sorbonne-universite.fr/hal-01207695/document https://hal.sorbonne-universite.fr/hal-01207695/file/bg-12-3171-2015.pdf https://doi.org/10.5194/bg-12-3171-2015 |
geographic |
Kerguelen Southern Ocean |
geographic_facet |
Kerguelen Southern Ocean |
genre |
Antarc* Antarctica Southern Ocean Copepods |
genre_facet |
Antarc* Antarctica Southern Ocean Copepods |
op_source |
ISSN: 1726-4170 EISSN: 1726-4189 Biogeosciences https://hal.sorbonne-universite.fr/hal-01207695 Biogeosciences, European Geosciences Union, 2015, 12 (11), pp.3171-3195. ⟨10.5194/bg-12-3171-2015⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.5194/bg-12-3171-2015 hal-01207695 https://hal.sorbonne-universite.fr/hal-01207695 https://hal.sorbonne-universite.fr/hal-01207695/document https://hal.sorbonne-universite.fr/hal-01207695/file/bg-12-3171-2015.pdf doi:10.5194/bg-12-3171-2015 |
op_rights |
http://creativecommons.org/licenses/by/ info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.5194/bg-12-3171-2015 |
container_title |
Biogeosciences |
container_volume |
12 |
container_issue |
11 |
container_start_page |
3171 |
op_container_end_page |
3195 |
_version_ |
1766246299720482816 |
spelling |
ftccsdartic:oai:HAL:hal-01207695v1 2023-05-15T13:47:05+02:00 Export fluxes in a naturally iron-fertilized area of the Southern Ocean – Part 2: Importance of diatom resting spores and faecal pellets for export Rembauville, M. Blain, S. Armand, L. QUEGUINER, Bernard Salter, I. Laboratoire d'Océanographie Microbienne (LOMIC) Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Observatoire océanologique de Banyuls (OOB) Université Pierre et Marie Curie - Paris 6 (UPMC)-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS) Department of Biological Sciences and Climate Futures - Macquarie University 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) Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI) 2015 https://hal.sorbonne-universite.fr/hal-01207695 https://hal.sorbonne-universite.fr/hal-01207695/document https://hal.sorbonne-universite.fr/hal-01207695/file/bg-12-3171-2015.pdf https://doi.org/10.5194/bg-12-3171-2015 en eng HAL CCSD European Geosciences Union info:eu-repo/semantics/altIdentifier/doi/10.5194/bg-12-3171-2015 hal-01207695 https://hal.sorbonne-universite.fr/hal-01207695 https://hal.sorbonne-universite.fr/hal-01207695/document https://hal.sorbonne-universite.fr/hal-01207695/file/bg-12-3171-2015.pdf doi:10.5194/bg-12-3171-2015 http://creativecommons.org/licenses/by/ info:eu-repo/semantics/OpenAccess ISSN: 1726-4170 EISSN: 1726-4189 Biogeosciences https://hal.sorbonne-universite.fr/hal-01207695 Biogeosciences, European Geosciences Union, 2015, 12 (11), pp.3171-3195. ⟨10.5194/bg-12-3171-2015⟩ [SDE]Environmental Sciences info:eu-repo/semantics/article Journal articles 2015 ftccsdartic https://doi.org/10.5194/bg-12-3171-2015 2021-11-21T03:03:08Z International audience The biological composition of the material exported to a moored sediment trap located under the winter mixed layer of the naturally fertilized Kerguelen Plateau in the Southern Ocean was studied over an annual cycle. Despite iron availability in spring, the annual particulate organic carbon (POC) export (98.2 mmol m−2) at 289 m was low, but annual biogenic silica export was significant (114 mmol m−2). This feature was related to the abundance of empty diatom cells and the ratio of full to empty cells exerted a first-order control in BSi : POC export stoichiometry of the biological pump. Chaetoceros Hyalochaete spp. and Thalassiosira antarctica resting spores were responsible for more than 60% of the annual POC flux that occurred during two very short export events of < 14 days in spring–summer. Relatively low diatom fluxes were observed over the remainder of the year. Faecal pellet contribution to annual carbon flux was lower (34%) and reached its seasonal maximum in autumn and winter (> 80%). The seasonal progression of faecal pellet types revealed a clear transition from small spherical shapes (small copepods) in spring, to larger cylindrical and ellipsoid shapes in summer (euphausiids and large copepods) and finally to large tabular shapes (salps) in autumn and winter. We propose in this high-biomass, low-export (HBLE) environment that small but highly silicified and fast-sinking resting spores are able to bypass the intense grazing pressure and efficient carbon transfer to higher trophic levels that are responsible for the low fluxes observed the during the remainder of the year. More generally our study also provides a statistical framework linking the ecological succession of diatom and zooplankton communities to the seasonality of carbon and silicon export within an iron-fertilized bloom region in the Southern Ocean. Article in Journal/Newspaper Antarc* Antarctica Southern Ocean Copepods Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) Kerguelen Southern Ocean Biogeosciences 12 11 3171 3195 |