Registro completo |
Provedor de dados: |
5
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País: |
France
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Título: |
Modeling biogeochemical processes in sediments from the Rhone River prodelta area (NW Mediterranean Sea)
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Autores: |
Pastor, L.
Cathalot, C.
Deflandre, B.
Viollier, E.
Soetaert, K.
Meysman, F. J. R.
Ulses, C.
Metzger, E.
Rabouille, C.
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Data: |
2011-05-27
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Ano: |
2011
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Resumo: |
In situ oxygen microprofiles, sediment organic carbon content, and pore-water concentrations of nitrate, ammonium, iron, manganese, and sulfides obtained in sediments from the Rhone River prodelta and its adjacent continental shelf were used to constrain a numerical diagenetic model. Results showed that (1) the organic matter from the Rhone River is composed of a fraction of fresh material associated to high first-order degradation rate constants (11-33 yr(-1)); (2) the burial efficiency (burial/input ratio) in the Rh boolean AND one prodelta (within 3 km of the river outlet) can be up to 80 %, and decreases to similar to 20% on the adjacent continental shelf 10-15 km further offshore; (3) there is a large contribution of anoxic processes to total mineralization in sediments near the river mouth, certainly due to large inputs of fresh organic material combined with high sedimentation rates; (4) diagenetic by-products originally produced during anoxic organic matter mineralization are almost entirely precipitated (> 97 %) and buried in the sediment, which leads to (5) a low contribution of the re-oxidation of reduced products to total oxygen consumption. Consequently, total carbon mineralization rates as based on oxygen consumption rates and using Redfield stoichiometry can be largely underestimated in such River-dominated Ocean Margins (RiOMar) environments.
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Tipo: |
Text
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Idioma: |
Inglês
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Identificador: |
https://archimer.ifremer.fr/doc/00303/41423/40614.pdf
https://archimer.ifremer.fr/doc/00303/41423/71282.pdf
DOI:10.5194/bg-8-1351-2011
https://archimer.ifremer.fr/doc/00303/41423/
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Editor: |
Copernicus GmbH
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Formato: |
application/pdf
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Fonte: |
Biogeosciences (1726-4170) (Copernicus GmbH), 2011-05-27 , Vol. 8 , N. 5 , P. 1351-1366
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Direitos: |
Author(s) 2011. CC Attribution 3.0 License.
info:eu-repo/semantics/openAccess
restricted use
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