FN Archimer Export Format
PT J
TI Modulation of the vertical particle transfer efficiency in the oxygen minimum zone off Peru
BT 
AF BRETAGNON, Marine
   PAULMIER, Aurelien
   GARCON, Veronique
   DEWITTE, Boris
   ILLIG, Serena
   LEBLOND, Nathalie
   COPPOLA, Laurent
   CAMPOS, Fernando
   VELAZCO, Federico
   PANAGIOTOPOULOS, Christos
   OSCHLIES, Andreas
   MARTIN HERNANDEZ-AYON, J.
   MASKE, Helmut
   VERGARA, Oscar
   MONTES, Ivonne
   MARTINEZ, Philippe
   CARRASCO, Edgardo
   GRELET, Jacques
   DESPREZ-DE-GESINCOURT, Olivier
   MAES, Christophe
   SCOUARNEC, Lionel
AS 1:1,2;2:1;3:1;4:1,3,4,5;5:1,6;6:7;7:7;8:8,9,10;9:11;10:12;11:13;12:14;13:10;14:1;15:9;16:15;17:11;18:16;19:17;20:1,18;21:17;
FF 1:;2:;3:;4:;5:;6:;7:;8:;9:;10:;11:;12:;13:;14:;15:;16:;17:;18:;19:;20:;21:;
C1 UPS CNRS IRD CNES, Lab Etud Geophys & Oceanog Spatiales, Toulouse, France.
   ACRI, Sophia Antipolis, France.
   CEAZA, Coquimbo, Chile.
   Univ Catolica Norte, Fac Ciencias Mar, Dept Biol, Coquimbo, Chile.
   Millennium Nucleus Ecol & Sustainable Management, Coquimbo, Chile.
   Univ Cape Town, LMI ICEMASA, MARE Inst, Dept Oceanog, Rondebosch, South Africa.
   Sorbonne Univ, CNRS, LOV, Villefranche Sur Mer, France.
   UNAC, Lima, Peru.
   IGP, Lima, Peru.
   CICESE, Ensenada, Baja California, Mexico.
   IMARPE, Callao, Peru.
   Aix Marseille Univ, Univ Toulon, CNRS, IRD,MIO,UM 110, Marseille, France.
   GEOMAR SFB754, Kiel, Germany.
   UABC, Ensenada, Baja California, Mexico.
   EPOC, Bordeaux, France.
   US IMAGO IRD, Brest, France.
   CNRS, DT, INSU, Brest, France.
   LOPS, Brest, France.
C2 UNIV TOULOUSE, FRANCE
   ACRI, FRANCE
   CEAZA, CHILE
   UNIV CATOLICA NORTE, CHILE
   ESMOI, CHILE
   UNIV CAPE TOWN, SOUTH AFRICA
   UNIV PARIS 06, FRANCE
   UNAC, PERU
   IGP, PERU
   CICESE, MEXICO
   IMARPE, PERU
   UNIV AIX MARSEILLE, FRANCE
   GEOMAR, GERMANY
   UNIV AUTONOMA BAJA CALIFORNIA SUR, MEXICO
   UNIV BORDEAUX, FRANCE
   IRD, FRANCE
   CNRS, FRANCE
   IRD, FRANCE
UM LOPS
IF 3.951
TC 11
UR https://archimer.ifremer.fr/doc/00486/59764/62889.pdf
   https://archimer.ifremer.fr/doc/00486/59764/62890.pdf
   https://archimer.ifremer.fr/doc/00486/59764/62891.pdf
   https://archimer.ifremer.fr/doc/00486/59764/62892.pdf
LA English
DT Article
CR AMOP
BO L'Atalante
AB The fate of the organic matter (OM) produced by marine life controls the major biogeochemical cycles of the Earth's system. The OM produced through photosynthesis is either preserved, exported towards sediments or degraded through remineralisation in the water column. The productive eastern boundary upwelling systems (EBUSs) associated with oxygen minimum zones (OMZs) would be expected to foster OM preservation due to low O-2 conditions. But their intense and diverse microbial activity should enhance OM degradation. To investigate this contradiction, sediment traps were deployed near the oxycline and in the OMZ core on an instrumented moored line off Peru. Data provided high-temporal-resolution O-2 series characterising two seasonal steady states at the upper trap: suboxic ([O-2] < 25 mu mol kg(-1)) and hypoxic-oxic (15 < [O-2] < 160 mu mol kg(-1)) in austral summer and winter-spring, respectively. The OMZ vertical transfer efficiency of particulate organic carbon (POC) between traps (T-eff) can be classifled into three main ranges (high, intermediate, low). These different T-eff ranges suggest that both predominant preservation (high T-eff > 50 %) and remineralisation (intermediate T-eff 20 < 50 % or low T-eff < 6 %) configurations can occur. An efficient OMZ vertical transfer (T-eff > 50 %) has been reported in summer and winter associated with extreme limitation in O-2 concentrations or OM quantity for OM degradation. However, higher levels of O-2 or OM, or less refractory OM, at the oxycline, even in a co-limitation context, can decrease the OMZ transfer efficiency to below 50 %. This is especially true in summer during intraseasonal wind-driven oxygenation events. In late winter and early spring, high oxygenation conditions together with high fluxes of sinking particles trigger a shutdown of the OMZ transfer (T-eff < 6 %). Transfer efficiency of chemical elements composing the majority of the flux (nitrogen, phosphorus, silica, calcium carbonate) follows the same trend as for carbon, with the lowest transfer level being in late winter and early spring. Regarding particulate isotopes, vertical transfer of delta N-15 suggests a complex pattern of N-15 impoverishment or enrichment according to T-eff modulation. This sensitivity of OM to O-2 fluctuations and particle concentration calls for further investigation into OM and O-2-driven remineralisation processes. This should include consideration of the intermittent behaviour of OMZ towards OM demonstrated in past studies and climate projections. 
PY 2018
PD AUG
SO Biogeosciences
SN 1726-4170
PU Copernicus Gesellschaft Mbh
VL 15
IS 16
UT 000442738300002
BP 5093
EP 5111
DI 10.5194/bg-15-5093-2018
ID 59764
ER

EF