Show simple item record

Importance of the vegetation-groundwater-stream continuum to understand transformation of biogenic carbon in aquatic systems – A case study based on a pine-maize comparison in a lowland sandy watershed (Landes de Gascogne, SW France)

hal.structure.identifierEnvironnements et Paléoenvironnements OCéaniques [EPOC]
dc.contributor.authorDEIRMENDJIAN, Loris
hal.structure.identifierEnvironnements et Paléoenvironnements OCéaniques [EPOC]
dc.contributor.authorANSCHUTZ, Pierre
hal.structure.identifierInteractions Sol Plante Atmosphère [UMR ISPA]
dc.contributor.authorMOREL, Christian
hal.structure.identifierInteractions Sol Plante Atmosphère [UMR ISPA]
dc.contributor.authorMOLLIER, Alain
hal.structure.identifierInteractions Sol Plante Atmosphère [UMR ISPA]
dc.contributor.authorAUGUSTO, Laurent
hal.structure.identifierÉcologie fonctionnelle et physique de l'environnement [EPHYSE]
dc.contributor.authorLOUSTAU, Denis
hal.structure.identifierEnvironnements et Paléoenvironnements OCéaniques [EPOC]
hal.structure.identifierUniversidade Federal Fluminense [Rio de Janeiro] [UFF]
dc.contributor.authorCOTOVICZ, Luiz Carlos
hal.structure.identifierEnvironnements et Paléoenvironnements OCéaniques [EPOC]
dc.contributor.authorBUQUET, Damien
hal.structure.identifierEnvironnements et Paléoenvironnements OCéaniques [EPOC]
hal.structure.identifierInstitut méditerranéen d'océanologie [MIO]
dc.contributor.authorLAJAUNIE, Katixa
hal.structure.identifierEnvironnements et Paléoenvironnements OCéaniques [EPOC]
dc.contributor.authorCHAILLOU, Gwénaëlle
hal.structure.identifierEnvironnements et Paléoenvironnements OCéaniques [EPOC]
hal.structure.identifierLaboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]
dc.contributor.authorVOLTZ, Baptiste
hal.structure.identifierEnvironnements et Paléoenvironnements OCéaniques [EPOC]
dc.contributor.authorCHARBONNIER, Celine
hal.structure.identifierEnvironnements et Paléoenvironnements OCéaniques [EPOC]
dc.contributor.authorPOIRIER, Dominique
hal.structure.identifierBiologie des Organismes et Ecosystèmes Aquatiques [BOREA]
dc.contributor.authorABRIL, Gwenaël
dc.date.accessioned2024-04-08T11:50:07Z
dc.date.available2024-04-08T11:50:07Z
dc.date.issued2019-04-15
dc.identifier.issn0048-9697
dc.identifier.urihttps://oskar-bordeaux.fr/handle/20.500.12278/195370
dc.description.abstractEnDuring land-aquatic transfer, carbon (C) and inorganic nutrients (IN) are transformed in soils, groundwater, and at the groundwater-surface water interface as well as in stream channels and stream sediments. However, processes and factors controlling these transfers and transformations are not well constrained, particularly with respect to land use effect. We compared C and IN concentrations in shallow groundwater and first-order streams of a sandy lowland catchment dominated by two types of land use: pine forest and maize cropland. Contrary to forest groundwater, crop groundwater exhibited oxic conditions all-year round as a result of higher evapotranspiration and better lateral drainage that decreased the water table below the organic-rich soil horizon, prevented the leaching of soil-generated dissolved organic carbon (DOC) in groundwater, and thus limited consumption of dissolved oxygen (O2). In crop groundwater, oxic conditions inhibited denitrification and methanogenesis resulting in high nitrate (NO3−; on average 1140 ± 485 μmol L−1) and low methane (CH4; 40 ± 25 nmol L−1) concentrations. Conversely, anoxic conditions in forest groundwater led to lower NO3− (25 ± 40 μmol L−1) and higher CH4 (1770 ± 1830 nmol L−1) concentrations. The partial pressure of carbon dioxide (pCO2; 30,650 ± 11,590 ppmv) in crop groundwater was significantly lower than in forest groundwater (50,630 ± 26,070 ppmv), and was apparently caused by the deeper water table delaying downward diffusion of soil CO2 to the water table. In contrast, pCO2 was not significantly different in crop (4480 ± 2680 ppmv) and forest (4900 ± 4500 ppmv) streams, suggesting faster degassing in forest streams resulting from greater water turbulence. Although NO3−concentrations indicated that denitrification occurred in riparian-forest groundwater, crop streams nevertheless exhibited important signs of spring and summer eutrophication such as the development of macrophytes. Stream eutrophication favored development of anaerobic conditions in crop stream sediments, as evidenced by increased ammonia (NH4+) and CH4 in stream waters and concomitant decreased in NO3− concentrations as a result of sediment denitrification. In crop streams, dredging and erosion of streambed sediments during winter sustained high concentration of particulate organic C, NH4+ and CH4. In forest streams, dissolved iron (Fe2+), NH4+ and CH4 were negatively correlated with O2 reflecting the gradual oxygenation of stream water and associated oxidations of Fe2+, NH4+ and CH4. The results overall showed that forest groundwater behaved as source of CO2 and CH4 to streams, the intensity depending on the hydrological connectivity among soils, groundwater, and streams. CH4 production was prevented in cropland in soils and groundwater, however crop groundwater acted as a source of CO2 to streams (but less so than forest groundwater). Conversely, in streams, pCO2 was not significantly affected by land use while CH4 production was enhanced by cropland. At the catchment scale, this study found substantial biogeochemical heterogeneity in C and IN concentrations between forest and crop waters, demonstrating the importance of including the full vegetation-groundwater-stream continuum when estimating land-water fluxes of C (and nitrogen) and attempting to understand their spatial and temporal dynamics.
dc.language.isoen
dc.publisherElsevier
dc.rights.urihttp://creativecommons.org/licenses/by-nc/
dc.subject.enCarbon dioxide
dc.subject.enMethane
dc.subject.enGroundwater
dc.subject.enStream
dc.subject.enLand use
dc.subject.enPine
dc.subject.enMaize
dc.title.enImportance of the vegetation-groundwater-stream continuum to understand transformation of biogenic carbon in aquatic systems – A case study based on a pine-maize comparison in a lowland sandy watershed (Landes de Gascogne, SW France)
dc.typeArticle de revue
dc.identifier.doi10.1016/j.scitotenv.2019.01.152
dc.subject.halSciences de l'environnement
dc.subject.halSciences de l'environnement/Milieux et Changements globaux
bordeaux.journalScience of the Total Environment
bordeaux.page613-629
bordeaux.volume661
bordeaux.hal.laboratoriesInteractions Soil Plant Atmosphere (ISPA) - UMR 1391*
bordeaux.institutionBordeaux Sciences Agro
bordeaux.institutionINRAE
bordeaux.peerReviewedoui
hal.identifierhal-02104943
hal.version1
hal.popularnon
hal.audienceInternationale
hal.origin.linkhttps://hal.archives-ouvertes.fr//hal-02104943v1
bordeaux.COinSctx_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.jtitle=Science%20of%20the%20Total%20Environment&rft.date=2019-04-15&rft.volume=661&rft.spage=613-629&rft.epage=613-629&rft.eissn=0048-9697&rft.issn=0048-9697&rft.au=DEIRMENDJIAN,%20Loris&ANSCHUTZ,%20Pierre&MOREL,%20Christian&MOLLIER,%20Alain&AUGUSTO,%20Laurent&rft.genre=article


Files in this item

FilesSizeFormatView

There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record