Mostrar el registro sencillo del ítem Bretagnon, Marine Paulmier, Aurélien Garçon, Véronique Dewitte, Boris Illig, Seréna Leblond, Nathalie Coppola, Laurent Campos, Fernando Velazco, Federico Panagiotopoulos, Christos Oschlies, Andreas Hernandez-Ayon, J. Martin Maske, Helmut Vergara, Oscar Montes Torres, Ivonne Martinez, Philippe Carrasco, Edgardo Grelet, Jacques Desprez-De-Gesincourt, Olivier Maes, Christophe Scouarnec, Lionel
dc.coverage.spatial Perú 2018-11-05T16:41:36Z 2018-11-05T16:41:36Z 2018
dc.identifier.citation Bretagnon, M., Paulmier, A., Garçon, V., Dewitte, B., Illig, S., Leblond, N., ... Scouarnec, L. (2018). Modulation of the vertical particle transfer efficiency in the oxygen minimum zone off Peru.==$Biogeosciences, 15$==(16), 5093-5111. es_ES
dc.identifier.govdoc index-oti2018
dc.description.abstract 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 O₂ 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 O₂ series characterising two seasonal steady states at the upper trap: suboxic ([O₂] < 25µmolkg−1) and hypoxic–oxic (15 < [O₂] < 160µmolkg−1) in austral summer and winter–spring, respectively. The OMZ vertical transfer efficiency of particulate organic carbon (POC) between traps (Teff) can be classified into three main ranges (high, intermediate, low). These different Teff ranges suggest that both predominant preservation (high Teff > 50%) and remineralisation (intermediate Teff 20 < 50% or low Teff < 6%) configurations can occur. An efficient OMZ vertical transfer (Teff > 50%) has been reported in summer and winter associated with extreme limitation in O₂ concentrations or OM quantity for OM degradation. However, higher levels of O₂ 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 (Teff < 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 δ15N suggests a complex pattern of 15N impoverishment or enrichment according to Teff modulation. This sensitivity of OM to O₂ fluctuations and particle concentration calls for further investigation into OM and O₂-driven remineralisation processes. This should include consideration of the intermittent behaviour of OMZ towards OM demonstrated in past studies and climate projections. es_ES
dc.format application/pdf es_ES
dc.language.iso eng es_ES
dc.publisher European Geosciences Union (EGU) es_ES
dc.relation.ispartof urn:issn:1726-4170
dc.rights info:eu-repo/semantics/openAccess es_ES
dc.rights.uri es_ES
dc.subject Minimum oxygen zone es_ES
dc.subject Particles es_ES
dc.subject Sedimentation es_ES
dc.subject Outcorps es_ES
dc.title Modulation of the vertical particle transfer efficiency in the oxygen minimum zone off Peru es_ES
dc.type info:eu-repo/semantics/article es_ES
dc.subject.ocde es_ES
dc.subject.ocde es_ES
dc.subject.ocde es_ES
dc.identifier.journal Biogeosciences es_ES
dc.description.peer-review Por pares es_ES
dc.identifier.doi es_ES




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