Mesoscale surface distribution of biogeochemical characteristics associated with a frontal system in the Crozet Basin during austral summer 1999.
International audience A mesoscale study was conducted in January and February 1999 in the Crozet Basin frontal zones (43°50¹ to 45°20¹S; 61°00¹ to 64°30¹E) within the southernmost and easternmost convergence area of the Antarctic Circumpolar Current (ACC) and the Agulhas Return Current (ARC). Distr...
Published in: | Marine Ecology Progress Series |
---|---|
Main Authors: | , , , , , , , , , , , , , , |
Other Authors: | , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2003
|
Subjects: | |
Online Access: | https://hal.science/hal-00700116 https://hal.science/hal-00700116/document https://hal.science/hal-00700116/file/Fiala_2003.pdf https://doi.org/10.3354/meps249001 |
id |
ftsorbonneuniv:oai:HAL:hal-00700116v1 |
---|---|
record_format |
openpolar |
institution |
Open Polar |
collection |
HAL Sorbonne Université |
op_collection_id |
ftsorbonneuniv |
language |
English |
topic |
Bacteria Biogenic silica Nutrients Frontal zones pCO2 Chlorophyll a Phytoplankton [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
spellingShingle |
Bacteria Biogenic silica Nutrients Frontal zones pCO2 Chlorophyll a Phytoplankton [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography Fiala, Michel Delille, B. Dubreuil, Catherine-Marie Kopcynska, E. Leblanc, Karine Morvan, J. Queguiner, Bernard Cailliau, P. Conan, Pascal Corvaisier, Rudolph Denis, Michel Frankignoulle, M. Oriol, L. Roy, Sylvaine Blain, Stéphane Mesoscale surface distribution of biogeochemical characteristics associated with a frontal system in the Crozet Basin during austral summer 1999. |
topic_facet |
Bacteria Biogenic silica Nutrients Frontal zones pCO2 Chlorophyll a Phytoplankton [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography |
description |
International audience A mesoscale study was conducted in January and February 1999 in the Crozet Basin frontal zones (43°50¹ to 45°20¹S; 61°00¹ to 64°30¹E) within the southernmost and easternmost convergence area of the Antarctic Circumpolar Current (ACC) and the Agulhas Return Current (ARC). Distribution of biogeochemical parameters was strongly linked to the merged Subtropical (STF) and Subantarctic (SAF) Fronts which mark the border between the cold and less saline subantarctic waters and the warm and more saline subtropical waters. This survey took place during a post-bloom period. Chlorophyll a concentrations were low throughout the study area ranging from 0.2 µg l-1 in the Polar Frontal Zone (PFZ) to 0.4 µg l-1 in the Subtropical Zone (STZ). Maximum chlorophyll a values (0.8 µg l-1) associated with an increase in biogenic silica concentration (from 0.03 to 0.34 µM) and a diatom peak (1.2 x 105 cells l-1) were encountered in the northeastern part of the STF edge. Despite northwardly decreasing concentrations of nitrates from 14 µM in the PFZ to 6 µM in the STZ, they were not the main factor limiting phytoplankton growth. Low silicic acid (mean = 0.6 µM) could have limited diatom development in the PFZ and the STZ where diatom numbers were low. In STZ waters, where average diatom numbers were highest, various species of Nitzschia and Thalassiothrix were common, but Pseudonitzschia spp. were dominant. Throughout the survey area, pico- and nano-sized cells dominated the phytoplankton assemblage, and their number was the highest in the STZ. Cyanobacteria, only present in subtropical waters >12.5°C, were the major component of the picoplankton size-fraction. While dinoflagellate numbers were low in the Subantarctic Zone (SAZ), their abundance and species numbers increased in the STZ, where Oxytoxum laticeps became dominant and several further large-size species of Prorocentrum, Ceratium and Gymnodinium appeared in addition to those at the STF. The distribution of different biogeochemical parameters ... |
author2 |
Université Pierre et Marie Curie - Paris 6 (UPMC) Unité d'Océanographie Chimique Interfacultary Center for Marine Research (MARE) Université de Liège-Université de Liège Laboratoire d'océanographie et de biogéochimie (LOB) Université de la Méditerranée - Aix-Marseille 2-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) Department of Antarctic Biology Polska Akademia Nauk = Polish Academy of Sciences = Académie polonaise des sciences (PAN) Ecole Nationale Supérieure de Chimie de Rennes (ENSCR) 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) |
format |
Article in Journal/Newspaper |
author |
Fiala, Michel Delille, B. Dubreuil, Catherine-Marie Kopcynska, E. Leblanc, Karine Morvan, J. Queguiner, Bernard Cailliau, P. Conan, Pascal Corvaisier, Rudolph Denis, Michel Frankignoulle, M. Oriol, L. Roy, Sylvaine Blain, Stéphane |
author_facet |
Fiala, Michel Delille, B. Dubreuil, Catherine-Marie Kopcynska, E. Leblanc, Karine Morvan, J. Queguiner, Bernard Cailliau, P. Conan, Pascal Corvaisier, Rudolph Denis, Michel Frankignoulle, M. Oriol, L. Roy, Sylvaine Blain, Stéphane |
author_sort |
Fiala, Michel |
title |
Mesoscale surface distribution of biogeochemical characteristics associated with a frontal system in the Crozet Basin during austral summer 1999. |
title_short |
Mesoscale surface distribution of biogeochemical characteristics associated with a frontal system in the Crozet Basin during austral summer 1999. |
title_full |
Mesoscale surface distribution of biogeochemical characteristics associated with a frontal system in the Crozet Basin during austral summer 1999. |
title_fullStr |
Mesoscale surface distribution of biogeochemical characteristics associated with a frontal system in the Crozet Basin during austral summer 1999. |
title_full_unstemmed |
Mesoscale surface distribution of biogeochemical characteristics associated with a frontal system in the Crozet Basin during austral summer 1999. |
title_sort |
mesoscale surface distribution of biogeochemical characteristics associated with a frontal system in the crozet basin during austral summer 1999. |
publisher |
HAL CCSD |
publishDate |
2003 |
url |
https://hal.science/hal-00700116 https://hal.science/hal-00700116/document https://hal.science/hal-00700116/file/Fiala_2003.pdf https://doi.org/10.3354/meps249001 |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
ISSN: 0171-8630 EISSN: 1616-1599 Marine Ecology Progress Series https://hal.science/hal-00700116 Marine Ecology Progress Series, 2003, 249, pp.1-14. ⟨10.3354/meps249001⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.3354/meps249001 hal-00700116 https://hal.science/hal-00700116 https://hal.science/hal-00700116/document https://hal.science/hal-00700116/file/Fiala_2003.pdf doi:10.3354/meps249001 |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.3354/meps249001 |
container_title |
Marine Ecology Progress Series |
container_volume |
249 |
container_start_page |
1 |
op_container_end_page |
14 |
_version_ |
1810493063454261248 |
spelling |
ftsorbonneuniv:oai:HAL:hal-00700116v1 2024-09-15T17:45:18+00:00 Mesoscale surface distribution of biogeochemical characteristics associated with a frontal system in the Crozet Basin during austral summer 1999. Fiala, Michel Delille, B. Dubreuil, Catherine-Marie Kopcynska, E. Leblanc, Karine Morvan, J. Queguiner, Bernard Cailliau, P. Conan, Pascal Corvaisier, Rudolph Denis, Michel Frankignoulle, M. Oriol, L. Roy, Sylvaine Blain, Stéphane Université Pierre et Marie Curie - Paris 6 (UPMC) Unité d'Océanographie Chimique Interfacultary Center for Marine Research (MARE) Université de Liège-Université de Liège Laboratoire d'océanographie et de biogéochimie (LOB) Université de la Méditerranée - Aix-Marseille 2-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) Department of Antarctic Biology Polska Akademia Nauk = Polish Academy of Sciences = Académie polonaise des sciences (PAN) Ecole Nationale Supérieure de Chimie de Rennes (ENSCR) 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) 2003-03-10 https://hal.science/hal-00700116 https://hal.science/hal-00700116/document https://hal.science/hal-00700116/file/Fiala_2003.pdf https://doi.org/10.3354/meps249001 en eng HAL CCSD Inter Research info:eu-repo/semantics/altIdentifier/doi/10.3354/meps249001 hal-00700116 https://hal.science/hal-00700116 https://hal.science/hal-00700116/document https://hal.science/hal-00700116/file/Fiala_2003.pdf doi:10.3354/meps249001 info:eu-repo/semantics/OpenAccess ISSN: 0171-8630 EISSN: 1616-1599 Marine Ecology Progress Series https://hal.science/hal-00700116 Marine Ecology Progress Series, 2003, 249, pp.1-14. ⟨10.3354/meps249001⟩ Bacteria Biogenic silica Nutrients Frontal zones pCO2 Chlorophyll a Phytoplankton [SDU.STU.OC]Sciences of the Universe [physics]/Earth Sciences/Oceanography info:eu-repo/semantics/article Journal articles 2003 ftsorbonneuniv https://doi.org/10.3354/meps249001 2024-07-25T23:47:33Z International audience A mesoscale study was conducted in January and February 1999 in the Crozet Basin frontal zones (43°50¹ to 45°20¹S; 61°00¹ to 64°30¹E) within the southernmost and easternmost convergence area of the Antarctic Circumpolar Current (ACC) and the Agulhas Return Current (ARC). Distribution of biogeochemical parameters was strongly linked to the merged Subtropical (STF) and Subantarctic (SAF) Fronts which mark the border between the cold and less saline subantarctic waters and the warm and more saline subtropical waters. This survey took place during a post-bloom period. Chlorophyll a concentrations were low throughout the study area ranging from 0.2 µg l-1 in the Polar Frontal Zone (PFZ) to 0.4 µg l-1 in the Subtropical Zone (STZ). Maximum chlorophyll a values (0.8 µg l-1) associated with an increase in biogenic silica concentration (from 0.03 to 0.34 µM) and a diatom peak (1.2 x 105 cells l-1) were encountered in the northeastern part of the STF edge. Despite northwardly decreasing concentrations of nitrates from 14 µM in the PFZ to 6 µM in the STZ, they were not the main factor limiting phytoplankton growth. Low silicic acid (mean = 0.6 µM) could have limited diatom development in the PFZ and the STZ where diatom numbers were low. In STZ waters, where average diatom numbers were highest, various species of Nitzschia and Thalassiothrix were common, but Pseudonitzschia spp. were dominant. Throughout the survey area, pico- and nano-sized cells dominated the phytoplankton assemblage, and their number was the highest in the STZ. Cyanobacteria, only present in subtropical waters >12.5°C, were the major component of the picoplankton size-fraction. While dinoflagellate numbers were low in the Subantarctic Zone (SAZ), their abundance and species numbers increased in the STZ, where Oxytoxum laticeps became dominant and several further large-size species of Prorocentrum, Ceratium and Gymnodinium appeared in addition to those at the STF. The distribution of different biogeochemical parameters ... Article in Journal/Newspaper Antarc* Antarctic HAL Sorbonne Université Marine Ecology Progress Series 249 1 14 |