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| Registros recuperados: 37 | |
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| Diaz, Melanie; Grasso, Florent; Le Hir, Pierre; Sottolichio, Aldo; Caillaud, Matthieu; Thouvenin, Benedicte. |
| Coastal environments are directly influenced by terrigenous inputs coming from rivers through estuaries. Quantifying the amount of nutrients and contaminants transported by sediments from continental areas to the sea is crucial for marine resources protection. However, the complexity of estuarine dynamics makes it difficult to quantify sediment fluxes from field measurements alone and requires numerical modeling. Thus, using a realistic 3D hydrodynamic and sediment transport model, this study aims at evaluating the influence of model empirical parameters on sediment fluxes and estimating uncertainties on mud and sand transfers at a macrotidal estuary mouth. A sensitivity analysis, considering changes in sediment transport parameters, revealed that the... |
| Tipo: Text |
Palavras-chave: Sensitivity analysis; Sediment fluxes; Numerical modeling; Mud; Sand; Gironde Estuary. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00617/72897/71906.pdf |
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| Pinazo, Christel; Ross, Oliver; Diaz, F.; Doglioli, A.m.; D'Ortenzio, F.; Estournel, C.; Forget, P.; Garnier, Valerie; Gutknecht, E.; Kersale, M.; Kessouri, F.; Lathuilière, C.; Marie, Louis; Marmain, J.; Marsaleix, P.; Perruche, C.; Petrenko, A.; Reffray, G.; Sourisseau, Marc; Taillandier, V.; Taupier-letage, I.; Testor, P.; Thouvenin, Benedicte; Ulses, C.; Eldin, G.. |
| Tipo: Text |
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| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00292/40336/41772.pdf |
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| Thouvenin, Benedicte; Salomon, Jean-claude. |
| In order to reproduce and investigate the marine circulation in the coastal tidal zone, and especially its three dimensional nature, it appeared interesting to develop a numerical mode! which could take account of the real bottom topography and the variations of the free surface. Navier-Stokes equations are solved in a straight forward manner, generalizing a finite difference technique already used in two-dimensional vertical models. To test the computational program, the mode! was applied to a number of flat bottom schematic basins, where we reproduced wind driven currents and tide propagation. Then we considered the particular case of a real channel and, finally, density currents associated with a salty wall. Mode) results are compared to theoretical... |
| Tipo: Text |
Palavras-chave: Modèle; Courant; Tridimensionnel; Seine; Côtier; Model; Current; Three-dimensional; Seine; Coastal. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/00113/22440/20127.pdf |
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| Gonzalez, Jean-louis; Dange, Catherine; Thouvenin, Benedicte. |
| Geochemical models are excellent tools for the understanding of trace elements dynamics, in particular in complex environments like estuaries. Their aim is to reproduce numerically the biogeochemical processes observed in the field or laboratory. The development and the use of this kind of tool requires: - in-situ data on the distribution in space and time of the elements studied and relationship with the environmental variables. - experimental data (mainly based on the use of radioactive analogues of the studied elements) for evaluation of model parameters and the validation of model assumptions. The model must be capable not only of reproducing the distribution of metals between the dissolved and particulate phases, but also of evaluating the... |
| Tipo: Text |
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| Ano: 2002 |
URL: https://archimer.ifremer.fr/doc/00479/59099/61737.pdf |
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| Menesguen, Alain; Dussauze, Morgan; Dumas, Franck; Thouvenin, Benedicte; Garnier, Valerie; Lecornu, Fabrice; Repecaud, Michel. |
| European directives (Water Framework Directive - WFD and Marine Strategy Framework Directive - MSFD) require a regular survey of several descriptors of the Environmental Status of coastal waters of the North-east Atlantic Ocean. Especially for the MSFD, which may concern large continental shelf areas where measurements are scarce, realistic ecological models can help assessing the Environmental Status. The ECO-MARS3D model of the pelagic ecosystem of the Bay of Biscay and English Channel continental shelf (NE Atlantic) has been developed for these applied purposes and validated against various types of historic data. This first paper deals with the basic biogeochemical version, which contains inorganic nutrients (NH4, NO3, PO4, Si(OH)4), three... |
| Tipo: Text |
Palavras-chave: Ecological 3D model; Continental shelf; Bay of Biscay and English Channel; Surface chlorophyll; Dissolved oxygen; MSFD. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00469/58098/60510.pdf |
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| Menesguen, Alain; Dussauze, Morgan; Lecornu, Fabrice; Dumas, Franck; Thouvenin, Benedicte. |
| Nitrate loadings to the French coastal waters of the Bay of Biscay and the English Channel have increased from 5 to 10 times during the four last decades, due to runoff on intensively fertilized agricultural watersheds. Eutrophication of this coastal zone is now a recurrent problem, with wellknown direct impacts (Ulva “green tides” on beaches, excessive phytoplanktonic blooms responsible for “coloured waters” and bottom hypoxia events offshore), but also indirect enhancement of the toxicity of some phytoplankton species, caused for instance by increased N:Si ratio in the coastal sea. In order to better guide the decision makers about nutrient loading reduction, Ifremer uses the so-called ECO-MARS3D biogeochemicalhydrodynamical model to simulate the present... |
| Tipo: Text |
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| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00197/30797/29166.pdf |
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| Pinazo, Christel; Fraysse, Marion; Doglioli, Andrea; Faure, Vincent Martin; Pairaud, Ivane; Petrenko, Anne; Thouvenin, Benedicte; Tronczynski, Jacek; Verney, Romaric; Yohia, Christophe. |
| In the framework of sustainable development, the anthropogenic impact of large coastal cities on the marine ecosystem is a key issue. This project aimed to improve our knowledge in marine ecosystem response to the anthropogenic supplies (from rivers, sewage outflows and atmosphere) from large cities. In particular, the goal is to underline how the physical forcing decreases or increases the anthropogenic impact on the coastal ecosystem and the assessment of the chemical contaminant (PCB) inputs (from city to sea) and exports (from mid-sea to open sea). |
| Tipo: Text |
Palavras-chave: Apports anthropiques; Baie de Marseille; Méditerranée nord-occidentale; Modélisation 3D; MARS3D; ECO3M; Couplage physique et biogéochimique; Anthropogenic supply; Bay of Marseille; North-Western Mediterranean Sea; 3D modelling; MARS3D; ECO3M; Physical-biogeochemical coupling. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00145/25592/23739.pdf |
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| Thouvenin, Benedicte. |
| The MET&OR module is a model, written in FORTRAN 90, which calculates the biogeochemical reactions between variables such as trace metal, radioactive tracers, organic or bacterial contaminants (biodegradation, decay, adsorption / desorption, photolysis, hydrolysis, volatilization, partition at equilibrium ..). It groups together classical reactions, described in the literature, to evaluate the source and sink terms which are integrated into the transport equations solved by a hydrodynamic model. It is intended more particularly for marine and coastal waters. This technical documentation aims to present the MET&OR module and the way in which it was coupled to the hydrodynamic model, in particular to MARS-3D. |
| Tipo: Text |
Palavras-chave: Modelisation; Biogéochimie; Contaminants métalliques; Organic contmainants; Contaminants bactériens; Modeling; Biogeochemical; Trace metals; Contaminants organiques; Bacterial contaminant. |
| Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00688/79972/83002.pdf |
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| Grasso, Florent; Verney, Romaric; Le Hir, Pierre; Thouvenin, Benedicte; Schulz, Elisabeth; Kervella, Youenn; Fard, I. Khojasteh Pour; Lemoine, J. -p.; Dumas, Franck; Garnier, Valerie. |
| Tidal pumping, baroclinic circulation and vertical mixing are known to be the main mechanisms responsible for the estuarine turbidity maximum (ETM) formation. However, the influence of hydro-meteorological conditions on ETM dynamics is still not properly grasped and requires further investigation to be quantified. Based on a realistic 3-dimensional numerical model of the macrotidal Seine Estuary (France) that accounts for mud and sand transport processes, the objective of this study is to quantify the influence of the main forcing (river flow, tides, waves) on the ETM location and mass changes. As expected, the ETM location is strongly modulated by semidiurnal tidal cycles and fortnightly timescales with a high sensitivity to river flow variations. The ETM... |
| Tipo: Text |
Palavras-chave: Estuary; Mud; Sand; Hydrodynamics; Turbidity maximum; Waves; Measurement; Modeling. |
| Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00416/52770/53638.pdf |
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| Gonzalez, Jean-louis; Thouvenin, Benedicte; Dange, Catherine; Chiffoleau, Jean-francois; Boutier, Bernard. |
| The role of particles in the fate and speciation of trace metals in macrotidal estuaries was studied using a surface complexation model (MOCO). Cadmium was selected as the target metal contaminant due to its reactivity in estuaries: cadmium behavior is mainly controlled by heterogeneous processes (sorption/desorption) related to salinity and suspended matter gradients. Various scenarios of suspended matter distribution according to salinity were simulated. The impact of surface properties (specific surface area, density of surface sites, acido-basic properties, and complexation constant) was evaluated using data collected on particles from the Gironde, Loire, and Seine estuaries. Our results show that particle surface properties, evaluated on the basis... |
| Tipo: Text |
Palavras-chave: Turbidity maximum; Speciation; Sorption; Particles; Modeling; Macrotidal estuaries; Cadmium. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2005.pdf |
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| Thouvenin, Benedicte; Gonzalez, Jean-louis. |
| Within the framework of the "Contaminants cycle and modeling" project of the BE department ("Biogeochemistry and Ecotoxicology") in Ifremer, two chemical contaminant modeling software were developed between 1998 and 2011 (Gonzalez JL, 2017): the MORGAN model (Model behavior of ORGANic contaminants in an aquatic environment) and the MOCO model (Surface Complexation MOdel for metallic COntaminants). These two models had been brought together in a single "zero-dimensional" software (known as MOMO), which made it possible to simulate the various processes affecting the behavior of chemical contaminants in a homogeneous mass of water (biodegradation, adsorption/desorption, photolysis, hydrolysis, volatilization, surface complexation, cation exchange,... |
| Tipo: Text |
Palavras-chave: Modelisation; Biogeochimie; Contaminants métalliques et organiques; Spéciation; Modeling; Biochemical; Trace metals - organic contaminants; Speciation. |
| Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00686/79771/82993.pdf |
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| Verney, Romaric; Jany, Cassandre; Thouvenin, Benedicte; Pairaud, Ivane; Vousdoukas, Michalis I.; Pinazo, Christel; Ardhuin, Fabrice; Cann, Philippe. |
| Human pressures on ecosystems have increased significantly over the last decades, and especially Mediterranean coasts are strongly impacted by the development of big cities and industrialized area, such as the Bay of Marseille. Prior to any investigations on ecological or contamination impacts, it was necessary to understand sediment dynamics and its response to natural extreme events such as storm or heavy rainfall events. In situ observations were dedicated to understand the behavior of bed sediments, and their spatial distribution. A benthic station was deployed for three months to observe the impact of extreme events on hydrodynamics and sediment dynamics in a critical zone of the study area. These measurementswere used to calibrate and validate the... |
| Tipo: Text |
Palavras-chave: Sediment dynamics; Large coastal cities; Urban pressure; Extreme events; Wave; Rainfall; Marseille. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00204/31515/29929.pdf |
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| Thouvenin, Benedicte; Le Hir, Pierre; Maurice, Laurence; Romana, Louis-alexandre. |
| A la demande de l'Association pour la Protection de l'Environnement de l'Estuaire de la Loire, une étude sur le cycle de l'oxygène dissous a été entreprise. Un modèle mathématique a été développé en plusieurs étapes, associé à des études sur le cycle de la matière organique dans le système bouchon vaseux/crème de vase et au développement d'un modèle de transport sédimentaire. Après la mise en place d'un modèle d'advection-dispersion dans l'estuaire, qui reproduit l'évolution de l'oxygène dissous sur un cycle lunaire, l'application du modèle de transport sédimentaire a permis le perfectionnement du modèle d'oxygène dissous, qui tient compte alors des variables particulaires aussi bien que dissoutes et décrit les variations de l'oxygène pendant cinq mois.... |
| Tipo: Text |
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| Ano: 1995 |
URL: http://archimer.ifremer.fr/doc/00082/19289/16884.pdf |
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| Pinazo, Christel; Doglioli, Andrea; Faure, Vincent; Fraysse, Marion; Ross, Oliver; Pairaud, Ivane; Petrenko, Anne; Thouvenin, Benedicte; Tronczynski, Jacek; Verney, Romaric; Yohia, Christophe. |
| Tipo: Text |
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| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00292/40337/38857.pdf |
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| Alekseenko, Elena; Thouvenin, Benedicte; Tronczynski, Jacek; Carlotti, F.; Garreau, Pierre; Tixier, Celine; Baklouti, Melika. |
| 3D coupled modeling approach is used for the PCB dispersion assessment in the Gulf of Lion and its transfer to zooplankton via biogeochemical processes. PCB budgets and fluxes between the different species of PCB: dissolved, particulate, biosorbed on plankton, assimilated by zooplankton, which are governed by different processes: adsorption/desorption, bacteria and plankton mortality, zooplankton excretion, grazing, mineralization, volatilization have been estimated. Model outputs were compared with the available in situ data. It was found that the Rhone River outflows play an important role in the organism contamination in the coastal zone, whereas the atmospheric depositions are rather more important in the offshore zones. The transfer of the available... |
| Tipo: Text |
Palavras-chave: PCBs; 3D coupled model; Gulf of Lions; Planktonic food web; CB153 fluxes. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00440/55177/56654.pdf |
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| Registros recuperados: 37 | |
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