@article{fdi:010073784,
  title = {{M}odulation of the vertical particle transfer efficiency in the oxygen minimum zone off {P}eru},
  author = {{B}retagnon, {M}. and {P}aulmier, {A}ur{\'e}lien and {G}arcon, {V}. and {D}ewitte, {B}oris and {I}llig, {S}erena and {L}eblond, {N}. and {C}oppola, {L}. and {C}ampos, {F}. and {V}elazco, {F}. and {P}anagiotopoulos, {C}. and {O}schlies, {A}. and {H}ernandez-{A}yon, {J}. {M}. and {M}aske, {H}. and {V}ergara, {O}. and {M}ontes, {I}. and {M}artinez, {P}. and {C}arrasco, {E}. and {G}relet, {J}acques and {D}esprez-{D}e-{G}esincourt, {O}. and {M}aes, {C}hristophe and {S}couarnec, {L}.},
  editor = {},
  language = {{ENG}},
  abstract = {{T}he fate of the organic matter ({OM}) produced by marine life controls the major biogeochemical cycles of the {E}arth's system. {T}he {OM} produced through photosynthesis is either preserved, exported towards sediments or degraded through remineralisation in the water column. {T}he productive eastern boundary upwelling systems ({EBUS}s) associated with oxygen minimum zones ({OMZ}s) would be expected to foster {OM} preservation due to low {O}-2 conditions. {B}ut their intense and diverse microbial activity should enhance {OM} degradation. {T}o investigate this contradiction, sediment traps were deployed near the oxycline and in the {OMZ} core on an instrumented moored line off {P}eru. {D}ata 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. {T}he {OMZ} vertical transfer efficiency of particulate organic carbon ({POC}) between traps ({T}-eff) can be classifled into three main ranges (high, intermediate, low). {T}hese 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. {A}n 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. {H}owever, 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 %. {T}his is especially true in summer during intraseasonal wind-driven oxygenation events. {I}n 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 %). {T}ransfer 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. {R}egarding particulate isotopes, vertical transfer of delta {N}-15 suggests a complex pattern of {N}-15 impoverishment or enrichment according to {T}-eff modulation. {T}his sensitivity of {OM} to {O}-2 fluctuations and particle concentration calls for further investigation into {OM} and {O}-2-driven remineralisation processes. {T}his should include consideration of the intermittent behaviour of {OMZ} towards {OM} demonstrated in past studies and climate projections.},
  keywords = {{PEROU} ; {PACIFIQUE}},
  booktitle = {},
  journal = {{B}iogeosciences},
  volume = {15},
  numero = {16},
  pages = {5093--5111},
  ISSN = {1726-4170},
  year = {2018},
  DOI = {10.5194/bg-15-5093-2018},
  URL = {https://www.documentation.ird.fr/hor/fdi:010073784},
}