Consulta: subjectFacets:"Modèle"
Registros recuperados: 24
Data/hora: 05/06/2024 14:12:44

Application du modèle MARS-3D à la rade de Toulon. Comparaison à des données historiques
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Tessier, Caroline.
Développé par le laboratoire DEL/AO à Brest et appliqué à la rade de Toulon, le modèle MARS-3D a été installé au laboratoire de Toulon. L'objectif est de mettre en route son application à Toulon et de contribuer à l'analyse en cours des résultats du modèle, en les· comparant aux mesures historiques. Dans ce rapport sont présentés les travaux faits pour réaliser ce double objectif: l'apprentissage du modèle dans sa conception et son utilisation, l'analyse des résultats et la comparaison avec des mesures ainsi qu'une simulation de traceurs. La comparaison du modèle avec les données a été réalisée sur la base des enregistrements faits en 1986-1987 en un point de mesure au centre de la grande rade. Or, l'emboîtement des modèles crée une contrainte sur le...
Tipo: Text
Palavras-chave: Modèle; Tridimensionnel; Méditerranée; Hydrodynamique; Validation; Toulon.
Ano: 2001
URL: https://archimer.ifremer.fr/doc/00431/54248/59141.pdf

Modélisation 0D des efflorescences d'Alexandrium en rade de Brest en compétition inter-spécifique
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Le Gland, Guillaume.
Since 2010, planktonic algae Alexandrium minutum, cause of the PSP (Paralytic Shellfish Poisoning) syndrome, has been proliferating in early summer in the bay of Daoulas, within the roadstead of Brest. During this internship, a model has been designed in order to derive these blooms from physical parameters (temperature, irradiance, nutrient supply, dilution rate …). In the model, A.minutum competes with 50 other plankton species with randomly attributed optimal temperature and nutrient uptake abilities. It turns out to reproduce well the bloom of 2012, with a correct date of maximum concentration and a relevant order of magnitude. It reproduces the order of magnitude of 2013 concentrations, but the bloom then is too spread in time around the maximum....
Tipo: Text
Palavras-chave: Alexandrium minutum; Phytoplancton; Efflorescence (bloom); Nutriments; Lumière; Température; Dilution; Absorption (uptake); Quota cellulaire; Croissance; Compétition; Modèle; Rade de Brest.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00209/32004/30442.pdf

Computed residual flow through the Dover Strait
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Salomon, Jean-claude; Breton, Marguerite; Guegueniat, Pierre.
A two-dimensional numerical model was used for the empirical deduction of a mathematical expression of water flow through the Dover Strait, for all conditions of tide, wind and ocean slope.  The theoretical results were correlated with sea measurements of radioactive tracers discharged at La Hague cape.  Nine actual years (1983-1991) were then examined, determining an average annual flow of 114000 mas-1 with a very high monthly variability, but with little difference from one year to the next.  These residual currents being highly sensitive to weather conditions, the mildness of the past few years has occasioned a decrease in fluxes towards the North Sea
Tipo: Text
Palavras-chave: Manche; Pas de Calais; Débit; Modèle; Marée; Channel; Dover Strait; Flow; Model; Tide.
Ano: 1993
URL: http://archimer.ifremer.fr/doc/1993/publication-542.pdf

Modélisation de la bioaccumulation de métaux traces (Hg, Cd, Pb, Cu et Zn) chez la moule, Mytilus galloprovincialis, en milieu méditerranéen
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Casas, Stellio.
Monitoring coastal contamination of trace metals using bivalve molluscs as quantitative bioindicators is widely used in many international monitoring programs. The bioaccumulation of metal within an organism results from the interaction between physiological (growth, loss of weight, absorption, accumulation), chemical (metal concentration, speciation, bioavailability) and environmental factors (temperature, SPM, chlorophyll). By utilizing the parameters above in this study, it appears that modeling metal dynamics in marine mussels is a reliable tool. The model allows understanding the bioaccumulation process which results from the interactions between biological, chemical and environmental factors. One of the objective of this study was to couple a...
Tipo: Text
Palavras-chave: Biomonitoring; Dynamic Energy Budget; Model; Trace metals; Bioaccumulation; Mytilus galloprovincialis; Mussel; Bioindicator; Surveillance; Budget énergétique dynamique; Modèle; Métaux traces; Bioaccumulation; Mytilus galloprovincialis; Moule; Bioindicateur.
Ano: 2005
URL: http://archimer.ifremer.fr/doc/2005/these-356.pdf

Modélisation hydro-sédimentaire de la baie du Mont Saint-Michel
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Cayocca, Florence; Dussauze, Morgan; Le Hir, Pierre; Bassoullet, Philippe; Jestin, Herve.
A numerical model for hydrodynamics and sediment transport is applied to Mont Saint Michel Bay, where ecological concerns are related to sediment transfers. Recent current datasets recorded on the tidal flat show the wind influence on the currents during neap tide. They are compared to model outputs. The simulation of sediment transfers driven by tides and waves accurately mimics the sediment repartition in the Bay.
Tipo: Text
Palavras-chave: Turbidité; Sédiments cohésifs; Modèle; Courant; Mont Saint Michel.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/acte-6274.pdf

Study of the manoeuvrability and security of a trawl gear
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Marichal, Dominique; Vincent, Benoit.
A complete method is presented for determining the static and dynamic behaviour of a fishing gear. The net, which is very flexible, is modelised by a set of rigid bars. The hydrodynamic forces, applied to each bar, are determined by combining and generalizing the Landweber and Morison hypothesis. A CFD method is used to calculate the forces on trawl doors. The fundamental principle of dynamics is completed with length equations expressing the elasticity of the bars. It leads to a set of second order non-linear differential equations, which is solved using a Runge-Kutta method. We will now present a few examples of the various applications of our works : the study of the trawl gear equilibrium in a uniform flow, an example of manoeuvrability (gyration of...
Tipo: Text
Palavras-chave: Runge Kutta; Elasticity; Simulation; Model; Trawl doors; Hydrodynamic; Fishing gear; Runge Kutta; Elasticite; Simulation; Modèle; Panneaux de chalut; Hydrodynamique; Engin de pêche.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/acte-4612.pdf

Estimation des stocks de bivalves en élevage et des épibiontes dans la lagune de Thau et modélisation de la dynamique des populations d'huîtres creuses (Crassostrea gigas, Thunberg)
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Gangnery, Aline.
In Thau Iagoon (Mediterranean Sea), shellfish are cultured in suspension. Molluscs are reared on ropes that are suspended on frames. Principal species concerned by breeding are Crassostrea gigas, Mytilus galloprovincialis and, in a less extent, Ostrea edulis. A new sampling method was developped to assess the total stock of cultured shellfish and was tested in July 1998 and April 1999. The total stock was found to be 19500 tons (± 1120 SE) in 1998 and 14100 tons (± 830 SE) in 1999, thus exhibiting temporal variations. Temporal differences in the total stock are mainly attributable to the breeding cycle but also to sorne exceptionnal events which occurred in Thau lageon in 1997 and 1998 (water anoxia, bacteriological crisis, bloom of toxic algae). In the...
Tipo: Text
Palavras-chave: Etang de Thau; Bivalves; Echantillonnage; Dynamique; Modèle; Epibiontes.
Ano: 1999
URL: http://archimer.ifremer.fr/doc/00443/55478/57008.pdf

Modélisation des cycles de l'azote et du phosphore dans les sédiments d'une lagune soumise à une exploitation conchylicole
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Chapelle, Annie; Mesnage, Valérie; Mazouni, Nabila; Deslous-paoli, Jean-marc; Picot, Bernadette.
A simulation of nitrogen and phosphorus exchanges for the sediment-water interface is presented, The aim of the sttudy is to understand the dynamic behaviour of an eutrophie coastal lagoon (Thau, France), ln situ experiments were performed to estimate the different pools of nitrogen and phosphorus in the water column and in the sediment. The diffusive fluxes between them were also estimated. A numerical mode1, simulating nitrogen and phosphorus cycles, was developed and calibrated with data recorded .at two seasons (winter and summer). This study leads to the conclusion that is necessary to know the different pools of nitrogen and phosphorus in order to estimate which fraction is bioavailable and the rate of nutrient exchange between sediment and water. It...
Tipo: Text
Palavras-chave: Modèle; Phosphore; Azote; Sédiment; Ecosystème conchylicole; Modelling; Phosphorus; Nitrogen; Sediment; Shellfish ecosystem.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/00039/15026/12360.pdf

Modélisation morphodynamique d'une embouchure tidale : Application aux Passes d'entrée du Bassin d'Arcachon
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Cayocca, Florence.
The Arcachon tidal inlet exhibits a particularly active morphology due to strong tidal currents and rough wave conditions. During the past 300 years, maximum and minimum extents of the Cap Ferret sand spit have resulted in a difference of 8 km while two channels have alternatively allowed circulation between the lagoon and the ocean.   A bidimensional horizontal morphodynarnic model was developed in order to simulate the system evolution under tidal forcing alone or under combined tide and wave action. Modelling at a scale of decades requires the definition of mean annual wave and tide conditions which are representative with respect to sediment transport. Medium term results thus give general trends of evolution. Driven by these average conditions and...
Tipo: Text
Palavras-chave: Littoral drift; Sediment transport; Tide; Waves; Arcachon lagoon; Tidal inlet; Modelling; Morphodynamic; Dérive littorale; Transport sédimentaire; Marée; Houle; Bassin d'Arcachon; Modèle; Morphodynamique.
Ano: 1996
URL: http://archimer.ifremer.fr/doc/1996/these-4520.pdf

Modélisation hydrodynamique de la dispersion à court terme dans une mer macrotidale: validation par des mesures à haute résolution de radiotraceurs solubles
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Bailly Du Bois, Pascal; Dumas, Franck.
DISPRO project aims to validate hydrodynamic models dispersion parameters by field data for the short-term (hours to week) and short distances (100 meters to 30 km). This project is based on a 2D instantaneous currents model with a mesh size of 110 m, coupled with high frequency field data collected in the release plume. At this step of the works, measurements confirm the reliability of the model during six hours following a release. This validation made possible developpement of models with known incertitude to simulate dispersion of dissolved substances in realistic conditions for normal or accidental situations in macrotidal seas.
Tipo: Text
Palavras-chave: Validation; Tritium; Dispersion; North sea; Hydrodynamic model; Validation; Tritium; Dispersion; Manche; Modèle.
Ano: 2004
URL: http://archimer.ifremer.fr/doc/2004/acte-564.pdf

Physiologie de la maturation et de la ponte chez l'huître creuse Crassostrea gigas - Résultats d'expériences conduites en 1996
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Soletchnik, Patrick; Faury, Nicole; Razet, Daniel; Geairon, Philippe; Goulletquer, Philippe.
L'objectif des expérimentations 1996 a consisté à comparer en "instantané" le potentiel de croissance de C. gigas à différents stades de maturité sexuelle, selon une méthodologie ayant déjà fait ses preuves en laboratoire. En accord avec les résultats de 1995, on retrouve une fragilité de C. gigas autour de la période de ponte. En 1996, les principales fonctions physiologiques (respiration, filtration et absorption) sont étudiées sur deux cohortes et pour 4 stades de maturité sexuelle. La "fragilité physiologique" des huîtres porte sur le stade de maturation avancée pour la cohorte 1993 et sur le stade de post-ponte pour la cohorte 1994. La méthodologie de conditionnement a été confirmée par ces expérimentations. Cependant on doit à nouveau noter les...
Tipo: Text
Palavras-chave: Crassostrea gigas; Mortalité; Ecophysiologie; Modèle; Marennes Oléron.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/00072/18362/15934.pdf

Les risques conchylicoles en Baie de Quiberon. Troisième partie : le risque d’hypoxie pour l’huître creuse Crassostrea gigas. Rapport final du projet Risco 2010-2013
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Stanisiere, Jean-yves; Mazurie, Joseph; Bouget, Jean-francois; Langlade, Aime; Gabellec, Raoul; Retho, Michael; Quinsat, Kevin; Leclerc, Emilie; Cugier, Philippe; Dussauze, Morgan; Menesguen, Alain; Dumas, Franck; Gohin, Francis; Augustin, Jean-marie; Ehrhold, Axel; Sinquin, Jean-marc; Goubert, Evelyne; Dreano, Alain.
The project “Risco”, supported by the “Pôle Mer” and funded by the Regional Council of Brittany, deals with specific risks of mortality of oysters, Crassostrea gigas, cultivated on the bottom, in a subtidal bay of South Brittany : the bay of Quiberon (56, France). Massive mortalities of oysters were reported in summer 2006 in this bay, exclusively located in the deep muddy area with a positive gradient eastward. A validated biogeochemical model was applied in order to simulate the dissolved oxygen over 2000-2006 : it revealed several episodes of hypoxia, more or less intense according to years, but with the same spatial distribution. This approach proved 2006 to be the most hypoxic year since 2000. The hypoxia was due to a rare conjunction of 3 factors :...
Tipo: Text
Palavras-chave: Baie Quiberon; Crassostrea gigas; Huître; Mortalité; Croissance; Hypoxie; Oxygène; Modèle; Upwelling; Loire; Vilaine; Quiberon; Crassostrea gigas; Oyster; Mortality; Growth; Hypoxia; Oxygen; Model; DEB; Upwelling; Loire; Vilaine.
Ano: 2013
URL: http://archimer.ifremer.fr/doc/00180/29131/27535.pdf

Mussel (Mytilus edulis) culture management along the Normandy coastline (France) : stock assessment and growth monitoring
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Goulletquer, Philippe; Joly, Jean-pierre; Le Gagneur, Eric; Ruelle, Francois.
The Normandy region is presently a leading shellfish rearing area in France yielding 35,000 metric tons of oysters C. gigas and Il,000 metric tons of mussels M. edulis on a yearly basis. Preliminary studies were initiated in 1989, 1991 and 1992 to develop the sampling strategy for cultured mussel stock assessment. Comprehensive mussel stock assessment and concomitant growth monitoring were carried out in 1993 to study mussel population and optimize overall s1l1ellfish culture management.  A three-stage cluster sampling strategy combined with stratification was tested on the 278 kms 'bouchot' type culture with a sampling effort of 275 units. Stratification was based upon two criteria including geographical sector and tidal level. Overall biomass was...
Tipo: Text
Palavras-chave: Model; Growth monitoring; Stock assessment; Mytilus edulis; Blue mussel; Modèle; Suivi de croissance; Estimation de stocks; Mytilus edulis L.; Moule bleue.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/1994/acte-3073.pdf

Modèle tridimensionnel de circulation et de dispersion en zone côtière à marée. Premiers essais : cas schématique et baie de Seine
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: 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

Modèle d'étude in vitro de Bonamia ostreae (Ascetospora), parasite intrahémocytaire d'Ostrea edulis. Etude d'intéractions cellulaires hôte-parasite
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Mourton, Chantal.
Oyster culture is, at a world scale, hit by variious epizooties, which are maintly caused by protozoans of the Phylum Ascetospora. Among them, Bonamia ostreae consitutes an appreciated model in order to study, at the cell scale, host-parasite relationships, as well as the immune role of hemocytes. Indeed, this parasite, which reproduces in hemocytes of Ostrea edulis, but cannot develop in Crassostea gigas. This development of an in vitro model for hemocyte-Bonamia relationships is presented. This includes the development and implementation of various techniques : making primocultures, protocol for infection with purified parasites, histological and immunoenzymatic analyses of infection. Such model allowed to study the interaction between host and...
Tipo: Text
Palavras-chave: Modèle; Histologie; Méthodologie; Primoculture; Ostrea edulis; Parasite; Hémocytes; Bonamia ostreae; Ascetospora; Protozoaire; Epizootie.
Ano: 1987
URL: http://archimer.ifremer.fr/doc/1987/rapport-3234.pdf

Approche de la capacité trophique d'un écosystème conchylicole
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Heral, Maurice; Deslous-paoli, Jean-marc; Prou, Jean.
After a short bibliographical study of the different approaches for determination of the trophic capacity of a bay for molluscs culture, the authors, with a global mode, show the relations between the growth performance of the oysters Crassostrea gigas in relation with the cultivated stocks. The volumes of consumed and assimilated food are calculated for the stocks in relation with the incoming volumes of water in the bay and the residence time for neap tide and spring tide. The authors find a decrease of growth rate in relation with the volume of consumed food. When it is above 60% and when the volume of assimilated food is above 20%, there is a large decrease of the growth of oysters.
Tipo: Text
Palavras-chave: Crassostrea gigas; Oysters; Stock assessment; Models; Food consumption; Growth; Biomass; Stock cultivé; Biomasse; Croissance; Modèle; Crassostrea gigas; Huîtres; Capacité trophique.
Ano: 1988
URL: http://archimer.ifremer.fr/doc/1988/acte-3834.PDF

Towed Gear Optimisation, application to trawls
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Roullot, Jean; Vincent, Benoit.
IFREMER has been developing and commercialising scientific software to help the conception and optimisation of any kind of trawl. This software named DynamiT makes available a "virtual flume tank" where tests can be achieved without any constraint due to scale effects or other limitation when physically testing out. DynamiT has been used numbers of times to simulate and optimise trawls by different net makers and by IFREMER. The software is based on the resolution of the mechanics (structure and hydrodynamic) equations of a model describing the actual trawl and its rigging. The "user friendly" interface allows the user to iterate "modification and observations" cycles to reach an optimised state of the fishing gear. The process can be used to reduce the...
Tipo: Text
Palavras-chave: Hydrodynamic; Fuel consumption; Simulation; Model; DynamiT; Software; Fishing; Hydrodynamique; Consommation de carburant; Simulation; Modèle; DynamiT; Logiciel; Pêche.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/acte-4613.pdf

Modélisation de la croissance des poissons en élevage
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Muller-feuga, Arnaud.
After a literature overview of growth models applied to intensively cultured fishes, a new one is proposed for assistance in rearing operations, with following characteristics. A simple and integratable mathematic expression simulates growth while eliminating individual weight influence. It gives way to a specific growth general definition. Temperature action mode on growth speed is simulated by substraction of two exponential functions. An automatic calculation method of thermal parameters is proposed. The torpid action of low temperatures is considered. Feeding ration influences growth through simple rules which are explicitly taken in account by mean of a two parameters function. The other growth factors, more difficult to seize, are expressed through a...
Tipo: Text
Palavras-chave: Modèle; Croissance; Élevage poissons; Pisciculture; Model; Fish culture.; Growth.
Ano: 1990
URL: http://archimer.ifremer.fr/doc/00183/29428/27794.pdf

Etude de la DYNAmique des MORtalités estivales (DYNAMOR) : Etude pluridisciplinaire intrasite du modèle de mortalité "plat-table" du bassin de Marennes Oléron
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Soletchnik, Patrick; Le Moine, Olivier; Razet, Daniel; Blouin, Frederic; Geairon, Philippe.
In the scope of the "Coastal ecology" thematics, the LCPC supervises a study which aims at understanding the causes and mechanisms of the summer mortality of C. Gigas. Different types of analysis conducted on the oyster (quality index, immunology, cell biology, etc.) enable the identification of a one month period preceding the acute mortality episode and during which the animals undergo a stress situation and become weaker. The energy balance (material balance) is close to zero for the most exposed stocks. Studies conducted on the environment included the search for pathogens and contaminants in the water column, the sediment and the animal, as well as the analysis of the hydrological features of the mass of water. The weakening period corresponds to an...
Tipo: Text
Palavras-chave: Hydrologie; Modèle; Contaminant; Sédiment; Colonne d'eau; Bilan énergétique; Crassostrea gigas; Huîtres; Mortalités estivales.
Ano: 2003
URL: http://archimer.ifremer.fr/doc/2003/acte-3391.pdf

Approche statistique des données MYTILOS - MYTIMED - MYTIAD - MYTIOR - MYTITURK. Contamination chimique en Méditerranée. Application du modèle de capteur "moule"
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Sargian, Peggy; Laroche, Sophie; Bouchoucha, Marc; Andral, Bruno.
Sur la base de l'expérience acquise dans le cadre du programme Rinbio, développé en partenariat avec l'Agence de l'Eau Rhône Méditerranée Corse depuis 1996, sept campagnes ont été réalisées sur l'ensemble de la Méditerranée : Mytilos en 2004, 2005 et 2006, Mytimed en 2007, Mytiad en 2008, Mytior en 2009 et Mytiturk en 2011. La reproductibilité de la technique du caging de moules au cours de ces différentes campagnes permet de disposer d'une première cartographie de la contamination chimique à l'échelle de l'ensemble du littoral méditerranéen. Les caractéristiques du capteur représenté par les moules varient cependant en fonction du milieu et en particulier de ses capacités trophiques, des périodes de stabulation et des lots initiaux d'échantillons, ce qui...
Tipo: Text
Palavras-chave: Rinbio; Méditerranée; Mytilos; Mytimed; Contaminant chimique; Modèle; Moules; Traitement statistique.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00233/34387/32781.pdf

Fonctionnement hydrodynamique du bassin de Thau. Validation écologique d’un modèle numerique de circulation (programme Écothau)
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Millet, B.
The wind-driven flow in the closed bassin de Thau is reproduced with a two-dimensional numerical model of horizontal ciruclation using an Alternate Direction Implicit scheme. A stochastic analysis of frequencies on a yearly time scale of the velocity fields computed in the model and a spatial and stochastic treatment of the term (H2 y2), similar to an effective coefficient of horizontal dispersion by shear effect are presented. This approach will allow the delineation, in a stochastic manner, of the main structures of the circulation in the lagoon and the spatial heterogeneity of its ecohydrodynamic features. Two attempts of analogical research are presented, with sorne examples of the spatial structure in the phytoplankton biomass and the map of the...
Tipo: Text
Palavras-chave: Lagune; Modèle; Circulation; Dispersion; Sédiment; Lagoon; Model; Circulation; Dispersion; Sediment.
Ano: 1989
URL: http://archimer.ifremer.fr/doc/00323/43399/43093.pdf

TRANSMER, un modèle hydrodynamique rapide et précis pour la simulation à moyen et long terme des transferts de radionucléides en Manche et dans le sud de la Mer du Nord
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Bailly Du Bois, Pascal; Dumas, Franck.
TRANSMER hydrodynamic model simulates dispersion of dissolved substances in seawater at the scale of the English Channel and the south of the North Sea with a mesh size of one kilometre and a time step of 30 minutes. It has been qualitatively and quantitatively validated by 1400 measurement of 125Sb in seawater. This model evaluates the medium- and long-term consequences of releases of soluble pollutants in the marine ecosystem under normal or accidental conditions, at a very low computation cost (it takes less than one hour to simulate one year).
Tipo: Text
Palavras-chave: English Channel; North Sea; Radionuclide; Concentration; Dispersion; Dissolved substances; Seawater; Hydrodynamic model; Modèle; Sb 125; Dispersion; Mer du Nord; Manche.
Ano: 2004
URL: http://archimer.ifremer.fr/doc/2004/acte-563.pdf

Modélisation des blooms de Gymnodinium mikimotoï le long de la façade atlantique française : répartition spatiale
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Loyer, Sophie; Lazure, Pascal; Gentien, Patrick; Menesguen, Alain.
In order to study the occurrence of Gymnodinium mikimotoï bloom on the French Atlantic coast, a three-dimensional model of primary production was set up. The biological model was coupled to a hydrodynamic model previously developed at Ifremer, by the intermediary of transport, diffusion and heat fluxes. The cycles of three limiting elements for the phytoplankton growth were modelised: nitrogen, phosphorus and silicon. The second phase of the study aimed at reproducing the summer dinoflagellate blooms. In this new approach a model of the species Gymnodinium mikimotoï was coupled with the previous biomass model which provides the physical and chemical environments. The study focuses on the results obtained by this specific sub-model. The parametrisation was...
Tipo: Text
Palavras-chave: Turbulence; Dinoflagellés; Gymnodinium mikimotoï; Modèle; Nutriments; Turbulence; Dinoflagellate; Gymnodinium mikimotoï; Model; Nutrients.
Ano: 2001
URL: https://archimer.ifremer.fr/doc/00479/59100/61738.pdf

Physiologie de la maturation et de la ponte chez l'huître creuse Crassostrea gigas
Provedor de dados: Institutional Archive of Ifreme (ArchiMer)
Autores: Soletchnik, Patrick; Geairon, Philippe; Razet, Daniel; Goulletquer, Philippe.
The physiological ecology of the Pacific oyster Crassostrea gigas was studied using a conditioning delayed by temperature. Experiments were carried out on five batches and 2 year-classes classified into 6 maturation stages. The scope for growth concerning the stages N*5 and 6 was nearly zero while positive for early stages as well as for the post-spawning stage. Moreover, the 1 year-old oysters showed a significant lowered scope for growth (-110 J/h) compared to adult oysters (-14 J/h), therefore demonstrating the increased sensitivity of young oysters to stressful environmental conditions. By comparing the experimental results with the current models, developed on immature oysters, facilitates the model parameters spécifications during gametogenesis. For...
Tipo: Text
Palavras-chave: Modelling; Ecophysiology; Mortality; Crassostrea gigas; Modèle; Ecophysiologie; Mortalité; Crassostrea gigas.
Ano: 1996
URL: http://archimer.ifremer.fr/doc/1996/rapport-1643.pdf