Significance of non-sinking particulate organic carbon and dark CO2 fixation to heterotrophic carbon demand in the mesopelagic northeast Atlantic
6 pages, 1 figure, 2 tables It is generally assumed that sinking particulate organic carbon (POC) constitutes the main source of organic carbon supply to the deep ocean¡̄s food webs. However, a major discrepancy between the rates of sinking POC supply (collected with sediment traps) and the prokaryo...
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ftcsic:oai:digital.csic.es:10261/80376 2024-02-11T10:06:45+01:00 Significance of non-sinking particulate organic carbon and dark CO2 fixation to heterotrophic carbon demand in the mesopelagic northeast Atlantic Baltar, Federico Arístegui, Javier Sintes, Eva Gasol, Josep M. Reinthaler, Thomas Herndl, Gerhard J. 2010-05 http://hdl.handle.net/10261/80376 https://doi.org/10.1029/2010GL043105 en eng American Geophysical Union https://doi.org/10.1029/2010GL043105 doi:10.1029/2010GL043105 issn: 0094-8276 e-issn: 1944-8007 Geophysical Research Letters 37(9): L09602 (2010) http://hdl.handle.net/10261/80376 open artículo http://purl.org/coar/resource_type/c_6501 2010 ftcsic https://doi.org/10.1029/2010GL043105 2024-01-16T09:51:17Z 6 pages, 1 figure, 2 tables It is generally assumed that sinking particulate organic carbon (POC) constitutes the main source of organic carbon supply to the deep ocean¡̄s food webs. However, a major discrepancy between the rates of sinking POC supply (collected with sediment traps) and the prokaryotic organic carbon demand (the total amount of carbon required to sustain the heterotrophic metabolism of the prokaryotes; i.e., production plus respiration, PCD) of deep-water communities has been consistently reported for the dark realm of the global ocean. While the amount of sinking POC flux declines exponentially with depth, the concentration of suspended, buoyant non-sinking POC (nsPOC; obtained with oceanographic bottles) exhibits only small variations with depth in the (sub)tropical Northeast Atlantic. Based on available data for the North Atlantic we show here that the sinking POC flux would contribute only 4̈C12% of the PCD in the mesopelagic realm (depending on the primary production rate in surface waters). The amount of nsPOC potentially available to heterotrophic prokaryotes in the mesopelagic realm can be partly replenished by dark dissolved inorganic carbon fixation contributing between 12% to 72% to the PCD daily. Taken together, there is evidence that the mesopelagic microheterotrophic biota is more dependent on the nsPOC pool than on the sinking POC supply. Hence, the enigmatic major mismatch between the organic carbon demand of the deep-water heterotrophic microbiota and the POC supply rates might be substantially smaller by including the potentially available nsPOC and its autochthonous production in oceanic carbon cycling models This research was supported by a predoctoral Fellowship of the Spanish Ministry of Education and Science (AP2005‐3932) to F.B., a grant of the Earth and Life Science Division of the Dutch Science Foundation (ALW‐NWO; ARCHIMEDES project, 835.20.023) to G.J.H. and a grant of the Spanish Ministry of Education and Science to J. A. (Remolinos Oceánicos y Deposiciones ... Article in Journal/Newspaper North Atlantic Northeast Atlantic Digital.CSIC (Spanish National Research Council) Remolinos ENVELOPE(-56.000,-56.000,-63.350,-63.350) Geophysical Research Letters 37 9 n/a n/a |
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Open Polar |
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Digital.CSIC (Spanish National Research Council) |
op_collection_id |
ftcsic |
language |
English |
description |
6 pages, 1 figure, 2 tables It is generally assumed that sinking particulate organic carbon (POC) constitutes the main source of organic carbon supply to the deep ocean¡̄s food webs. However, a major discrepancy between the rates of sinking POC supply (collected with sediment traps) and the prokaryotic organic carbon demand (the total amount of carbon required to sustain the heterotrophic metabolism of the prokaryotes; i.e., production plus respiration, PCD) of deep-water communities has been consistently reported for the dark realm of the global ocean. While the amount of sinking POC flux declines exponentially with depth, the concentration of suspended, buoyant non-sinking POC (nsPOC; obtained with oceanographic bottles) exhibits only small variations with depth in the (sub)tropical Northeast Atlantic. Based on available data for the North Atlantic we show here that the sinking POC flux would contribute only 4̈C12% of the PCD in the mesopelagic realm (depending on the primary production rate in surface waters). The amount of nsPOC potentially available to heterotrophic prokaryotes in the mesopelagic realm can be partly replenished by dark dissolved inorganic carbon fixation contributing between 12% to 72% to the PCD daily. Taken together, there is evidence that the mesopelagic microheterotrophic biota is more dependent on the nsPOC pool than on the sinking POC supply. Hence, the enigmatic major mismatch between the organic carbon demand of the deep-water heterotrophic microbiota and the POC supply rates might be substantially smaller by including the potentially available nsPOC and its autochthonous production in oceanic carbon cycling models This research was supported by a predoctoral Fellowship of the Spanish Ministry of Education and Science (AP2005‐3932) to F.B., a grant of the Earth and Life Science Division of the Dutch Science Foundation (ALW‐NWO; ARCHIMEDES project, 835.20.023) to G.J.H. and a grant of the Spanish Ministry of Education and Science to J. A. (Remolinos Oceánicos y Deposiciones ... |
format |
Article in Journal/Newspaper |
author |
Baltar, Federico Arístegui, Javier Sintes, Eva Gasol, Josep M. Reinthaler, Thomas Herndl, Gerhard J. |
spellingShingle |
Baltar, Federico Arístegui, Javier Sintes, Eva Gasol, Josep M. Reinthaler, Thomas Herndl, Gerhard J. Significance of non-sinking particulate organic carbon and dark CO2 fixation to heterotrophic carbon demand in the mesopelagic northeast Atlantic |
author_facet |
Baltar, Federico Arístegui, Javier Sintes, Eva Gasol, Josep M. Reinthaler, Thomas Herndl, Gerhard J. |
author_sort |
Baltar, Federico |
title |
Significance of non-sinking particulate organic carbon and dark CO2 fixation to heterotrophic carbon demand in the mesopelagic northeast Atlantic |
title_short |
Significance of non-sinking particulate organic carbon and dark CO2 fixation to heterotrophic carbon demand in the mesopelagic northeast Atlantic |
title_full |
Significance of non-sinking particulate organic carbon and dark CO2 fixation to heterotrophic carbon demand in the mesopelagic northeast Atlantic |
title_fullStr |
Significance of non-sinking particulate organic carbon and dark CO2 fixation to heterotrophic carbon demand in the mesopelagic northeast Atlantic |
title_full_unstemmed |
Significance of non-sinking particulate organic carbon and dark CO2 fixation to heterotrophic carbon demand in the mesopelagic northeast Atlantic |
title_sort |
significance of non-sinking particulate organic carbon and dark co2 fixation to heterotrophic carbon demand in the mesopelagic northeast atlantic |
publisher |
American Geophysical Union |
publishDate |
2010 |
url |
http://hdl.handle.net/10261/80376 https://doi.org/10.1029/2010GL043105 |
long_lat |
ENVELOPE(-56.000,-56.000,-63.350,-63.350) |
geographic |
Remolinos |
geographic_facet |
Remolinos |
genre |
North Atlantic Northeast Atlantic |
genre_facet |
North Atlantic Northeast Atlantic |
op_relation |
https://doi.org/10.1029/2010GL043105 doi:10.1029/2010GL043105 issn: 0094-8276 e-issn: 1944-8007 Geophysical Research Letters 37(9): L09602 (2010) http://hdl.handle.net/10261/80376 |
op_rights |
open |
op_doi |
https://doi.org/10.1029/2010GL043105 |
container_title |
Geophysical Research Letters |
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37 |
container_issue |
9 |
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1790604661527412736 |