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dc.rights.licenseopenen_US
hal.structure.identifierInstitut des Sciences de la Terre d'Orléans - UMR7327 [ISTO]
hal.structure.identifierBiogéosystèmes Continentaux - UMR7327
dc.contributor.authorALBÉRIC, Patrick
hal.structure.identifierDepartamento de Geoquímica
dc.contributor.authorPÉREZ, Marcela A.P.
hal.structure.identifierGéosciences Environnement Toulouse [GET]
dc.contributor.authorMOREIRA-TURCQ, Patricia
hal.structure.identifierInstitut de Physique du Globe de Paris [IPGP]
dc.contributor.authorBENEDETTI, Marc F.
hal.structure.identifierDivision of Soil and Water Management Leuven
dc.contributor.authorBOUILLON, Steven
hal.structure.identifierEnvironnements et Paléoenvironnements OCéaniques [EPOC]
hal.structure.identifierLaboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques [LOCEAN]
dc.contributor.authorABRIL, Gwenaël
dc.date.accessioned2024-03-13T09:52:22Z
dc.date.available2024-03-13T09:52:22Z
dc.date.issued2018
dc.identifier.urihttps://oskar-bordeaux.fr/handle/20.500.12278/188763
dc.description.abstractEnGiven the relative scarcity of stable isotope data on dissolved organic carbon (DOC) in the Amazon Basin, we hypothesized that the variability in DOC sources may be underestimated in such major river basins. To explore the links between the mainstem and tributaries and the floodplain, particular efforts were made during five distinct cruises at different stages of the hydrograph between October 2008 and January 2011, to document the spatial and temporal variation of DOC concentrations and δ13C-DOC in the central Amazon River system (Brazil). Based on more than 200 data, the spatial and temporal variability of δ13C-DOC values was found to be larger than previously reported in the same area. Although a small range of variation was observed throughout the hydrological cycle in the upper reach of the studied section (–29.2 to –29.5‰ in the Rio Negro and –28.7 to –29.0‰ in the Rio Solimões), a much larger one (–28.0 to –34.6‰) was found in the lower reach of the river, as the proportion of open lakes increased downstream in the floodplains. The low variability in the upper reaches suggests constant and homogeneous DOC sources from upland soils and flooded forest, while lower δ13C-DOC values recorded in the lower reach mainstem at high and falling waters can be attributed to a greater export of plankton-derived 13C-depleted DOC from flooded lakes. Noteworthy are the higher δ13C-DOC values measured in the Rio Madeira and the associated flooded lakes (–26.5 to –28.8‰), which may reflect the imprint from upland headwaters and a weaker density of flooded forest in the watershed. The higher δ13C-DOC values observed in the lower reach during low waters are still not fully understood. Floating meadows principally consisting of C4 macrophytes were found to increase δ13C-DOC values by ∼1.5‰ in their vicinity, but this impact was no longer noticeable at distances of ∼10 m from the plant rafts. This rather modest 13C-enrichment suggests rapid decomposition and/or dilution of this wetland-derived DOC.
dc.description.sponsorshipCARBon biogeochemistry and atmospheric exchanges in the AMAzon river system - ANR-08-BLAN-0221en_US
dc.language.isoENen_US
dc.rightsAttribution-NonCommercial-NoDerivs 3.0 United States*
dc.rights.urihttp://creativecommons.org/licenses/by-nc-nd/3.0/us/*
dc.subject.enDOC
dc.subject.enC4 plant raft
dc.subject.enRunoff cycle
dc.subject.enAmazon Basin
dc.subject.en13C/12C
dc.title.enVariation of the isotopic composition of dissolved organic carbon during the runoff cycle in the Amazon River and the floodplains
dc.typeArticle de revueen_US
dc.identifier.doi10.1016/j.crte.2017.11.001en_US
dc.subject.halPlanète et Univers [physics]/Sciences de la Terre/Géochimieen_US
bordeaux.journalComptes Rendus Géoscienceen_US
bordeaux.page65-75en_US
bordeaux.volume350en_US
bordeaux.hal.laboratoriesEPOC : Environnements et Paléoenvironnements Océaniques et Continentaux - UMR 5805en_US
bordeaux.issue1-2en_US
bordeaux.institutionUniversité de Bordeauxen_US
bordeaux.institutionCNRSen_US
bordeaux.teamECOBIOCen_US
bordeaux.peerReviewedouien_US
bordeaux.inpressnonen_US
bordeaux.import.sourcehal
hal.identifierinsu-01678204
hal.version1
hal.popularnonen_US
hal.audienceInternationaleen_US
hal.exportfalse
workflow.import.sourcehal
dc.rights.ccCC BY-NC-NDen_US
bordeaux.COinSctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=Comptes%20Rendus%20G%C3%A9oscience&rft.date=2018&rft.volume=350&rft.issue=1-2&rft.spage=65-75&rft.epage=65-75&rft.au=ALB%C3%89RIC,%20Patrick&P%C3%89REZ,%20Marcela%20A.P.&MOREIRA-TURCQ,%20Patricia&BENEDETTI,%20Marc%20F.&BOUILLON,%20Steven&rft.genre=article


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