Consulta: subjectFacets:"Diagenèse précoce"
Registros recuperados: 2
Data/hora: 05/06/2024 08:26:42

Transformation de la phase solide à travers l’estuaire de la Loire en relation avec son environnement chimique et biologique
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Thibault De Chanvalon, Aubin.
Before reaching the ocean, riverine particles from the Loire watershed undergo important chemical transformations in the estuary. This study aims to identify and characterize main processes involving iron (and to a lesser extent Al, Mn, PO4 3- and rare earths elements). Suspended particulate matter data show that 15% of their iron is lost through the estuary. Reductive iron dissolution during deposition periods is likely to explain most of this loss. However, estuarine sediments are characterized by high spatial heterogeneity due to macrofaunal activities. To overcome this difficulty, new methodologies of high resolution and two-dimensional analyses and calculation of pore water, sediment and benthic meiofauna were developed. These developments enable to...
Tipo: Text
Palavras-chave: Estuaire; Fer; Phosphore; Nitrate; Foraminifère benthique; Diagenèse précoce; Loire; Bioturbation; Estuary; Iron; Phosphorus; Nitrate; Benthic foraminifera; Precocious diagenesis; Loire; Bioturbation.
Ano: 2016
URL: https://archimer.ifremer.fr/doc/00498/60932/64325.pdf

Comportement du cadmium et du mercure lors de la diagenèse précoce et flux à l'interface eau-sédiments en zone littorale
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Gonzalez, Jean-louis.
The early diagenesis of Cd and Hg has been studied in different coastal areas (vasière Ouest-Gironde, Pertuis d'Antioche, baie de Marennes-Oléron). For these two metals, the fluxes at the sediment-water interface have been calculated. Considering only molecular diffusion, the diffusionnal fluxes of Cd and Hg to the colurnn water are negligible with regard to both the particular fluxes to the sediments and the inputs of the "Gironde" and "Charente" ·,estuaries. The take into account of the different processes which affect the ex changes at the interface (erosion, bioturbation) permits more realistic an estimation of the role of sediments in the geochemical cycle of Cd and Hg. The results show that up to 50% of particular Cd and Hg which are integrated into...
Tipo: Text
Palavras-chave: Cadmium; Mercure; Eaux intrstitielles; Diagenèse précoce; Flux; Interface eaux-sédiments; Bioturbation; Modélisation; Cadmium; Mercury; Pore waters; Early diagenesis; Fluxes; Sediment-water interface; Bioturbation; Modelling.
Ano: 1992
URL: http://archimer.ifremer.fr/doc/00442/55402/56920.pdf