FN Archimer Export Format
PT J
TI Particulate barium tracing of significant mesopelagic carbon remineralisation in the North Atlantic
BT 
AF LEMAITRE, Nolwenn
   PLANQUETTE, Helene
   PLANCHON, Frederic
   SARTHOU, Geraldine
   JACQUET, Stephanie
   GARCIA-IBANEZ, Maria Isabel
   GOURAIN, Arthur
   CHEIZE, Marie
   MONIN, Laurence
   ANDRE, Luc
   LAHA, Priya
   TERRYN, Herman
   DEHAIRS, Frank
AS 1:1,2,9;2:1;3:1;4:1;5:3;6:4,5;7:1,6;8:1;9:7;10:7;11:8;12:8;13:2;
FF 1:;2:;3:;4:;5:;6:;7:;8:;9:;10:;11:;12:;13:;
C1 IUEM, UMR 6539, Lab Sci Environm Marin LEMAR, Technopole Brest Iroise, F-29280 Plouzane, France.
   Vrije Univ Brussel, Analyt Environm & Geochem, Earth Syst Sci Res Grp, Brussels, Belgium.
   Aix Marseille Univ, CNRS INSU, Univ Toulon, IRD,MIO,UM110, F-13288 Marseille, France.
   Bjerknes Ctr Climate Res, Uni Res Climate, N-5008 Bergen, Norway.
   IIM CSIC, Inst Invest Marinas, Eduardo Cabello 6, Vigo 36208, Spain.
   Univ Liverpool, Sch Environm Sci, Ocean Sci Dept, Liverpool L69 3GP, Merseyside, England.
   Royal Museum Cent Africa, Earth Sci Dept, Leuvensesteenweg 13, B-3080 Tervuren, Belgium.
   Vrije Univ Brussel, Dept Mat & Chem, SURF Res Grp, Brussels, Belgium.
   ETH, Inst Geochem & Petr, Dept Earth Sci, Zurich, Switzerland.
C2 UBO, FRANCE
   UNIV VRIJE BRUSSEL, BELGIUM
   UNIV AIX MARSEILLE, FRANCE
   BCCR, NORWAY
   CSIC, SPAIN
   UNIV LIVERPOOL, UK
   ROYAL MUSEUM CENT AFRICA, BELGIUM
   UNIV VRIJE BRUSSEL, BELGIUM
   ETH ZURICH, SWITZERLAND
UM LEMAR
IN DOAJ
IF 3.951
TC 15
UR https://archimer.ifremer.fr/doc/00412/52308/53075.pdf
   https://archimer.ifremer.fr/doc/00412/52308/53076.pdf
   https://archimer.ifremer.fr/doc/00412/52308/56303.pdf
   https://archimer.ifremer.fr/doc/00412/52308/56304.pdf
LA English
DT Article
CR GEOVIDE
BO Pourquoi pas ?
AB The remineralisation of sinking particles by prokaryotic heterotrophic activities 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 an 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 in the same order of magnitude than other fluxes obtained by 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, highlighting the important impact of the mesopelagic remineralisation on the biological carbon pump with a near-zero, deep (> 1000 m) carbon sequestration efficiency in spring 2014. 
PY 2018
PD APR
SO Biogeosciences
SN 1726-4170
PU Copernicus Gesellschaft Mbh
VL 15
IS 8
UT 000430485900001
BP 2289
EP 2307
DI 10.5194/bg-15-2289-2018
ID 52308
ER

EF