Particulate barium tracing of significant mesopelagic carbon remineralisation in the North Atlantic
19 pages, 4 tables, 10 figures.-- Nolwenn Lemaitre . et al.-- This work is distributed under the Creative Commons Attribution 4.0 License The remineralisation of sinking particles by prokaryotic heterotrophic activity is important for controlling oceanic carbon sequestration. Here, we report mesopel...
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ftcsic:oai:digital.csic.es:10261/165432 2024-02-11T10:05:36+01:00 Particulate barium tracing of significant mesopelagic carbon remineralisation in the North Atlantic Lemaitre, Nolwenn García-Ibáñez, Maribel I. Dehairs, Frank Ministerio de Economía y Competitividad (España) 2018 http://hdl.handle.net/10261/165432 https://doi.org/10.5194/bg-15-2289-2018 https://doi.org/10.13039/501100003329 en eng European Geosciences Union #PLACEHOLDER_PARENT_METADATA_VALUE# info:eu-repo/grantAgreement/MINECO/Plan Estatal de Investigación Científica y Técnica y de Innovación 2013-2016/CTM2013-41048-P Publisher's version https://doi.org/10.5194/bg-15-2289-2018 Sí Biogeosciences 15: 2289-2307 (2018) 1726-4170 http://hdl.handle.net/10261/165432 doi:10.5194/bg-15-2289-2018 1726-4189 http://dx.doi.org/10.13039/501100003329 open artículo http://purl.org/coar/resource_type/c_6501 2018 ftcsic https://doi.org/10.5194/bg-15-2289-201810.13039/501100003329 2024-01-16T10:30:43Z 19 pages, 4 tables, 10 figures.-- Nolwenn Lemaitre . et al.-- This work is distributed under the Creative Commons Attribution 4.0 License The remineralisation of sinking particles by prokaryotic heterotrophic activity is important for controlling oceanic carbon sequestration. Here, we report mesopelagic particulate organic carbon (POC) remineralisation fluxes in the North Atlantic along the GEOTRACES-GA01 section (GEOVIDE cruise; May–June 2014) using the particulate biogenic barium (excess barium; Baxs) proxy. Important mesopelagic (100–1000 m) Baxs differences were observed along the transect depending on the intensity of past blooms, the phytoplankton community structure, and the physical forcing, including downwelling. The subpolar province was characterized by the highest mesopelagic Baxs content (up to 727 pmol L−1), which was attributed to an intense bloom averaging 6 mg chl a m−3 between January and June 2014 and by an intense 1500 m deep convection in the central Labrador Sea during the winter preceding the sampling. This downwelling could have promoted a deepening of the prokaryotic heterotrophic activity, increasing the Baxs content. In comparison, the temperate province, characterized by the lowest Baxs content (391 pmol L−1), was sampled during the bloom period and phytoplankton appear to be dominated by small and calcifying species, such as coccolithophorids. The Baxs content, related to oxygen consumption, was converted into a remineralisation flux using an updated relationship, proposed for the first time in the North Atlantic. The estimated fluxes were of the same order of magnitude as other fluxes obtained using independent methods (moored sediment traps, incubations) in the North Atlantic. Interestingly, in the subpolar and subtropical provinces, mesopelagic POC remineralisation fluxes (up to 13 and 4.6 mmol C m−2 d−1, respectively) were equalling and occasionally even exceeding upper-ocean POC export fluxes, deduced using the 234Th method. These results highlight the important impact of the ... Article in Journal/Newspaper Labrador Sea North Atlantic Digital.CSIC (Spanish National Research Council) |
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Open Polar |
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Digital.CSIC (Spanish National Research Council) |
op_collection_id |
ftcsic |
language |
English |
description |
19 pages, 4 tables, 10 figures.-- Nolwenn Lemaitre . et al.-- This work is distributed under the Creative Commons Attribution 4.0 License The remineralisation of sinking particles by prokaryotic heterotrophic activity is important for controlling oceanic carbon sequestration. Here, we report mesopelagic particulate organic carbon (POC) remineralisation fluxes in the North Atlantic along the GEOTRACES-GA01 section (GEOVIDE cruise; May–June 2014) using the particulate biogenic barium (excess barium; Baxs) proxy. Important mesopelagic (100–1000 m) Baxs differences were observed along the transect depending on the intensity of past blooms, the phytoplankton community structure, and the physical forcing, including downwelling. The subpolar province was characterized by the highest mesopelagic Baxs content (up to 727 pmol L−1), which was attributed to an intense bloom averaging 6 mg chl a m−3 between January and June 2014 and by an intense 1500 m deep convection in the central Labrador Sea during the winter preceding the sampling. This downwelling could have promoted a deepening of the prokaryotic heterotrophic activity, increasing the Baxs content. In comparison, the temperate province, characterized by the lowest Baxs content (391 pmol L−1), was sampled during the bloom period and phytoplankton appear to be dominated by small and calcifying species, such as coccolithophorids. The Baxs content, related to oxygen consumption, was converted into a remineralisation flux using an updated relationship, proposed for the first time in the North Atlantic. The estimated fluxes were of the same order of magnitude as other fluxes obtained using independent methods (moored sediment traps, incubations) in the North Atlantic. Interestingly, in the subpolar and subtropical provinces, mesopelagic POC remineralisation fluxes (up to 13 and 4.6 mmol C m−2 d−1, respectively) were equalling and occasionally even exceeding upper-ocean POC export fluxes, deduced using the 234Th method. These results highlight the important impact of the ... |
author2 |
Ministerio de Economía y Competitividad (España) |
format |
Article in Journal/Newspaper |
author |
Lemaitre, Nolwenn García-Ibáñez, Maribel I. Dehairs, Frank |
spellingShingle |
Lemaitre, Nolwenn García-Ibáñez, Maribel I. Dehairs, Frank Particulate barium tracing of significant mesopelagic carbon remineralisation in the North Atlantic |
author_facet |
Lemaitre, Nolwenn García-Ibáñez, Maribel I. Dehairs, Frank |
author_sort |
Lemaitre, Nolwenn |
title |
Particulate barium tracing of significant mesopelagic carbon remineralisation in the North Atlantic |
title_short |
Particulate barium tracing of significant mesopelagic carbon remineralisation in the North Atlantic |
title_full |
Particulate barium tracing of significant mesopelagic carbon remineralisation in the North Atlantic |
title_fullStr |
Particulate barium tracing of significant mesopelagic carbon remineralisation in the North Atlantic |
title_full_unstemmed |
Particulate barium tracing of significant mesopelagic carbon remineralisation in the North Atlantic |
title_sort |
particulate barium tracing of significant mesopelagic carbon remineralisation in the north atlantic |
publisher |
European Geosciences Union |
publishDate |
2018 |
url |
http://hdl.handle.net/10261/165432 https://doi.org/10.5194/bg-15-2289-2018 https://doi.org/10.13039/501100003329 |
genre |
Labrador Sea North Atlantic |
genre_facet |
Labrador Sea North Atlantic |
op_relation |
#PLACEHOLDER_PARENT_METADATA_VALUE# info:eu-repo/grantAgreement/MINECO/Plan Estatal de Investigación Científica y Técnica y de Innovación 2013-2016/CTM2013-41048-P Publisher's version https://doi.org/10.5194/bg-15-2289-2018 Sí Biogeosciences 15: 2289-2307 (2018) 1726-4170 http://hdl.handle.net/10261/165432 doi:10.5194/bg-15-2289-2018 1726-4189 http://dx.doi.org/10.13039/501100003329 |
op_rights |
open |
op_doi |
https://doi.org/10.5194/bg-15-2289-201810.13039/501100003329 |
_version_ |
1790602701274349568 |