Afficher la notice abrégée

dc.rights.licenseopenen_US
hal.structure.identifierEnvironnements et Paléoenvironnements OCéaniques [EPOC]
dc.contributor.authorANSCHUTZ, Pierre
ORCID: 0000-0001-5331-7974
IDREF: 076300331
hal.structure.identifierInstitut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux [IPREM]
dc.contributor.authorBOUCHET, Sylvain
hal.structure.identifierBiologie des Organismes et Ecosystèmes Aquatiques [BOREA]
dc.contributor.authorABRIL, Gwenaël
hal.structure.identifierInstitut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux [IPREM]
dc.contributor.authorBRIDOU, Romain
hal.structure.identifierInstitut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux [IPREM]
dc.contributor.authorTESSIER, Emmanuel
hal.structure.identifierInstitut des sciences analytiques et de physico-chimie pour l'environnement et les materiaux [IPREM]
dc.contributor.authorAMOUROUX, David
dc.date.accessioned2024-01-25T15:22:20Z
dc.date.available2024-01-25T15:22:20Z
dc.date.issued2019-04
dc.identifier.issn0278-4343en_US
dc.identifier.urihttps://oskar-bordeaux.fr/handle/20.500.12278/187526
dc.description.abstractEnIn coastal environments, oscillating redox conditions represent a functional state affecting organic matter mineralization. Such transient diagenetic processes remain difficult to study in situ, and we therefore designed a specific reactor to provide experimental results that are environmentally relevant in this context. Here, we present the results of two independent experiments carried out with sediment having contrasting Fe, Mn contents, collected from a coastal tidal lagoon (the Arcachon bay) and a mesotidal estuary (Adour river). Sediment and overlying water were mixed to form slurries that were submitted to redox oscillations to assess the diagenetic mechanisms that affect N, P, Fe, Mn, and S. Changing from anoxic to oxic conditions, we observed a rapid oxidation of dissolved Fe(II) and dissolved inorganic phosphorus (DIP) was apparently trapped by the newly formed Fe-oxyhydroxides (Fe-ox). DIP was totally titrated in the coastal lagoon sediment, but not in estuarine sediment, where the initial amount of Fe available was lower. In both experiments, Mn(II) was only slowly oxidized during the oxidation events and a major part of Mn(II) was adsorbed on new Fe-ox. In coastal lagoon sediment, ammonium remained constant in oxic conditions while nitrate was produced from organic-N mineralization. On the contrary, in estuarine sediment, ammonium was quantitatively oxidized to nitrate. When the conditions became anoxic again, direct reduction of nitrate to ammonium occurred in coastal lagoon sediment. Anaerobic production of nitrate occurred in estuarine sediment, probably because Mn-oxides (Mn-ox), which had a high concentration, acted as an oxidant for ammonium. Consequently, nitrate production prevented Fe(II) accumulation. The Mn-N-Fe coupling outlined here is an apparent indirect oxidation of Fe(II) by Mn-ox through anaerobic nitrification (with Mn-ox) and denitrification (with Fe-ox). This coupling also implied P availability because of the strong control of P by Fe. These experimental results show that nutrient dynamics in oscillatory redox environments such as the estuarine turbidity zone, bioturbated sediment, or tidal permeable sediments highly depends on Mn-and Fe-ox availability.
dc.language.isoENen_US
dc.rights.urihttp://creativecommons.org/licenses/by-nc/
dc.subject.enCoastal sediments
dc.subject.enManganese oxide
dc.subject.enIron oxide
dc.subject.enNutrients
dc.subject.enRedox oscillation
dc.subject.enBenthic biogeochemistry
dc.title.enIn vitro simulation of oscillatory redox conditions in intertidal sediments: N, Mn, Fe, and P coupling
dc.typeArticle de revueen_US
dc.identifier.doi10.1016/j.csr.2019.03.007en_US
dc.subject.halPlanète et Univers [physics]en_US
dc.subject.halPlanète et Univers [physics]/Sciences de la Terreen_US
dc.subject.halPlanète et Univers [physics]/Sciences de la Terre/Géochimieen_US
dc.subject.halChimieen_US
dc.subject.halChimie/Chimie analytiqueen_US
bordeaux.journalContinental Shelf Researchen_US
bordeaux.page33-41en_US
bordeaux.volume177en_US
bordeaux.hal.laboratoriesEPOC : Environnements et Paléoenvironnements Océaniques et Continentaux - UMR 5805en_US
bordeaux.institutionUniversité de Bordeauxen_US
bordeaux.institutionCNRSen_US
bordeaux.teamECOBIOCen_US
bordeaux.peerReviewedouien_US
bordeaux.inpressnonen_US
bordeaux.import.sourcehal
hal.identifierhal-02104948
hal.version1
hal.popularnonen_US
hal.audienceInternationaleen_US
hal.exportfalse
workflow.import.sourcehal
dc.rights.ccPas de Licence CCen_US
bordeaux.COinSctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=Continental%20Shelf%20Research&rft.date=2019-04&rft.volume=177&rft.spage=33-41&rft.epage=33-41&rft.eissn=0278-4343&rft.issn=0278-4343&rft.au=ANSCHUTZ,%20Pierre&BOUCHET,%20Sylvain&ABRIL,%20Gwena%C3%ABl&BRIDOU,%20Romain&TESSIER,%20Emmanuel&rft.genre=article


Fichier(s) constituant ce document

Thumbnail

Ce document figure dans la(les) collection(s) suivante(s)

Afficher la notice abrégée