Consulta: creatorFacets:"Heral, Maurice"
Registros recuperados: 148
Data/hora: 02/06/2024 07:40:07

Amelioration de la forme et de la qualite de l'huitre Crassostrea gigas Thunberg dans les claires de Marennes-Oleron.
Provedor de dados: 5
Autores: Deslous-paoli, Jean-marc; Zanette, Yvan; Heral, Maurice; Masse, Henri; Garnier, Jacqueline.
The breeding of Pacific oysters Crassostra gigas, in non tidal ponds, before commercialization, brings about an improvement of the shell and of the quantity and quality of the tissues. In fact, the Berthome's indice (1978) moves from 1.36 in June to 0.68 December, and the density of the shell increases in the same time from 1.79 to 1.98. On the other hand, the percentage of tissues in the oyster is 12.4% at the end of gametogenesis and more than 9% at the end of breeding. The dry tissues are composed of 10.3 of ash, 40.3% of proteins, 12.6% of lipids and 9% of carbohydrate. 95% of the carbohydrate are glycogen. The resulting energetic values are measured to 5.10 cal-mg super(-1) of dry tissues ash free.
Tipo: Text
Palavras-chave: Crassostrea gigas; Tissues; Biochemical composition; Shells; Growth; Oyster culture.
Ano: 1981
URL: http://archimer.ifremer.fr/doc/1981/publication-1892.pdf

Rapport annuel d'activité 1981 du Laboratoire Cultures Marines et Aménagement du Littoral de La Tremblade
Provedor de dados: 5
Autores: Heral, Maurice.
Rapport d'activité du Laboratoire Cultures Marines et Aménagement du Littoral de La Tremblade concernant l'année 1981
Tipo: Text
Palavras-chave: Conchyliculture; Production; Gisement naturel; Estimation stock; Production; Valorisation claires ostréicoles; Culture palourde; Sélection génétique; Crassostrea gigas; Ruditapes decussatus; Ruditapes philippinarum; Marennes Oléron.
Ano: 1981
URL: http://archimer.ifremer.fr/doc/00070/18119/15667.pdf

Rejets d'elevage de poissons en eau de mer: Consequences pour l'huitre Crassostrea gigas.
Provedor de dados: 5
Autores: Coeurdacier, J.-m.; Heral, Maurice; Liange, M.; Moreau, Jean; Prou, Jean; Razet, Daniel; Williot, P.
Reject waters from sea fish-ponds of rearing trout and turbot show increased ammonia and phosphate values. Protid, lipid and glucid contents of the waters remain low, with total values which do not overpass 1.7 mg.l super(1). After showing that the oysters were likely to absorb sewage from fish farming ponds, the authors examine whether, for epidemiologic and rearing methods reason, it is possible for both types of farming to cohabit as for as zoopathology is concerned. The possible accumulation of antibiotic in mollusks and antibioresistance transfer to germs may be pathogenic for man, are also discussed.
Tipo: Text
Palavras-chave: Aeromonas hydrophila Escherichia coli Crassostrea gigas Bivalvia Antibiotics Growth Environmental effects Bacteria Shellfish culture; Pollution effects Fish culture.
Ano: 1982
URL: http://archimer.ifremer.fr/doc/1982/publication-1855.pdf

Influence du climat sur le recrutement et sur la production d'huîtres cultivées (Crassostrea angulata et Crassostrea gigas) dans le bassin de Marennes-Oléron (France)
Provedor de dados: 5
Autores: Heral, Maurice; Deslous-paoli, Jean-marc; Prou, Jean.
Recruitment, marketed yield and cultivated biomasses of oysters Crassostrea angulata and Crassostrea gigas are compared to climatic indices for the period 1885-1984. Temperature plays a role up on the date of spawning but explains only partially the failure of recruitment, which has less influence on the marketed yield than on the total biomass Contrary to the sensitivity of wild molluscan stocks to climatic conditions, yield and biomass of these cultivated stocks are not hightly correlated to the annual and seasonal indices of rainfall and air temperature.
Tipo: Text
Palavras-chave: Marennes Oleron Bay; Climatic conditions; Recrutment; Crassostrea gigas; Crassostrea angulata; Oysters; Marennes Oléron; Facteurs climatiques; Recrutement; Crassostrea gigas; Crassostrea angulata; Huîtres.
Ano: 1986
URL: http://archimer.ifremer.fr/doc/1986/acte-2972.pdf

Modélisation de l'écosystème du bassin de Marennes-Oléron
Provedor de dados: 5
Autores: Bacher, Cedric; Menesguen, Alain; Raillard, Olivier; Heral, Maurice; Deslous-paoli, Jean-marc; Razet, Daniel.
Une approche analytique permet de coupler un modèle physique avec un modèle biologique qui prédit la croissance des huîtres en fonction de la quantité, de la qualité de la nourriture particulaire et de la température. Ce modèle montre clairement l'effet de surcharge du bassin induisant un ralentissement des performances de croissance avec un gradient marqué du nord au sud. Un modèle phytoplanctonique basé sur les apports respectifs en nitrates de la Charente et de l'océan permet de prédire la production primaire en fonction de la température et de la transparence de l'eau. Une simulation supprimant les apports de la Charente permet de préciser la quantité de phytoplancton dépendant de ces apports. Un troisième modè le s'applique à représenter dans une...
Tipo: Text
Palavras-chave: Modèle de croissance huîtres; Modèle phytoplanctonique; Remise en suspension; Marennes-Oléron.
Ano: 1990
URL: http://archimer.ifremer.fr/doc/00439/55045/56481.pdf

Le marais salé des pertuis charentais : à la recherche d'un développement durable
Provedor de dados: 5
Autores: Prou, Jean; Heral, Maurice.
Sustainable development of the marine part of the wetlands located on the Atlantic coast of France (Pertuis Charentais) implies the difficult integration of European and national regulations in the regional frame. Spatial and temporal patterns of this area show the strong relationship between human activities (salt, sheIlfish farming, agriculture, fisheries...) and physical evolution of this area. Regulations based on zoning have to be completed by more precise studies including the major role of water uses regulated by human practices.
Tipo: Text
Palavras-chave: Regulations; Shellifish farming; Sustainable development; Wetlands; Pertuis Charentais; Ostréiculture; Développement durable; Marais salé.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/1997/acte-3235.pdf

Hydrobiologie du bassin de Marennes-Oléron - Résultats du Réseau National d'Observation : 1977 à 1981
Provedor de dados: 5
Autores: Heral, Maurice; Razet, Daniel; Deslous-paoli, Jean-marc; Manaud, Francois; Truquet, Isabelle; Garnier, Jacqueline.
After determining the seasonal features of the hydrobiology of the Marennes-Oléron's estuarine complex in 1976 and 1977 (Héral et al, 1983), based on seasonal campaigns conducted in 15 stations sampled in a tide half-cycle, it was proposed to monitor 5 stations spread out over the entire basin (figure 1) as part of the National Observation Network (RNO) with two monthly samples taken, one at neap tide, the other at spring tide. In the same way, station 3, at the centre of the basin, was sampled at tide half-cycle, on the same days but with a special effort to determine the dissolved and particulate organic substances. The goal of this paper is to introduce the results of the RNO's hydrobiological parameters at the stations of the Charente (5) estuary, the...
Tipo: Text
Palavras-chave: Substances organiques particulaires; Substances organiques dissoutes; Marennes Oléron; Hydrobiologie.
Ano: 1984
URL: http://archimer.ifremer.fr/doc/1984/publication-2934.pdf

Problèmes posés par l'analyse des relations trophiques huîtres-milieu
Provedor de dados: 5
Autores: Deslous-paoli, Jean-marc; Heral, Maurice; Zanette, Yohann.
A relation between the evolution of biochemical components of molluscs and the available amount of food is difficult to establish. In addition to energy relations we tried to use a factorial correspondance analysis in the study on relation between the evolution of biochemical reserves of tissues of Crassostrea gigas Thunberg and the nutritional ability of the environment. The analysis showed a negative correlation between storing of carbohydrate and lipid reserves and amounts of mineral seston. In the same way, an accumulation of these reserves varies with the biomass of phytoplanctonic populations.
Tipo: Text
Palavras-chave: Marennes Oléron; Potential feeding; Oysters; Trophic relation; Marennes Oléron; Nourriture potentielle; Huîtres; Relations trophiques.
Ano: 1981
URL: http://archimer.ifremer.fr/doc/1981/acte-2939.pdf

Amélioration de l'évaluation des stocks de mollusques cultivés en Charente- Maritime
Provedor de dados: 5
Autores: Bacher, Cedric; Deslous-paoli, Jean-marc; Heral, Maurice; Prou, Jean.
The expansion of shellfish culture businesses (oysters, mussels, clams...) gives way to a competition for the use of limited food resources, especially in the Marennes-Oléron basin where water circulation is slow. Increasing the amount of cultivated molluscs leads, from a biological point of view, to:- a drop in growth performances- a rise in chronic mortalities, higher and higher, due to a weakness in the physiological state with a lack of stocks which would have compensated the habitat seasonal shortages (end of winter, etc...)- a greater weakness to diseases, linked to a deficient physiological state and a density rise which increases the proximity rate and thus, parasite propagation speed.For these primary reasons, and for the future of oyster culture,...
Tipo: Text
Palavras-chave: Modélisation; Estimation; Echantillonnage; Mollusques; Marennes Oléron; Evaluation stocks.
Ano: 1986
URL: http://archimer.ifremer.fr/doc/1986/rapport-3841.PDF

Rapport de la campagne de la "THALASSA" en manche orientale
Provedor de dados: 5
Autores: Heral, Maurice; Lassus, Patrick; Halguand, D.
Le navire océanographique "Thalassa" a effectué du 15 janvier au 14 février 1975 une série de prélèvements et de mesures, dans le secteur côtier compris entre le cap d'Antifer et Dunkerque.   La mission embarquée comprenait les chercheurs et techniciens de l'ISTPM, ainsi qu'un représentant d'EDF pendant la première semaine de campagne.   Ces travaux avaient pour but essentiel d'apporter des informations préliminaires à des études biologiques et écologiques destinées à évaluer l'impact de futures centrales thermiques nucléaires sur l'environnement marin de la Manche orientale et du sud de la Mer du Nord.
Tipo: Text
Ano: 1975
URL: http://archimer.ifremer.fr/doc/00046/15728/13130.pdf

Caracteristiques saisonnieres de l'hydrobiologie du complexe estuariende Marennes-Oleron (France).
Provedor de dados: 5
Autores: Heral, Maurice; Razet, Daniel; Deslous-paoli, Jean-marc; Berthome, Jean-paul; Garnier, J.
Four seasonal compaigns providing a sampling of 15 stations each followed during half a tide cycle, i.e. 120 water samples permit the definition of the main hydrobiological features of Marennes-Oleron Bay: salinity and turbidity, phytoplanktonic biomasses, ATP concentrations. The authors suggest that a new way of adapted sampling to their objectives, will work out in the future by sampling during tidal cycles but as frequently as possible.
Tipo: Text
Palavras-chave: Seasonal variations; Salinity; ATP; Estuaries; Turbidity; Hydrobiology; Salinity; Phytoplankton; Estuaries; Biomass; Hydrobiology; Physicochemical properties; Phytoplankton; Environmental conditions; Biomass.
Ano: 1982
URL: http://archimer.ifremer.fr/doc/1982/publication-1854.pdf

Novel observations underlying the fast growth of suspension-feeding shellfish in turbid environments: Mytilus edulis
Provedor de dados: 5
Autores: Hawkins, Ajs; Smith, Rfm; Bayne, Bl; Heral, Maurice.
For the tirst time for any benthic filter-feeder, this study documents each component process of nutrient acquisition through natural tidal variations of food availabillty. The organic content of seston available during both neap and spring tides in the bay of Marennes-Oléron. France, decreased from 28 to 8 % with mcreasing seston concentration from 10 to about 90 mg total particulate mass 1(1). Throughout this tidal variation, the blue mussel Mylilus edulis L. cleared more water of particles as seston availability increased. Rejection of fillered material as pseudofaeces prior to ingestion remained a constant fraction of about 0 .93 x the mass of filtered material, so that ingestion rate showed no signs of stabilising at even the highest food...
Tipo: Text
Palavras-chave: Seston composition; Tidal variation; Mussel; Mytilus edulis; Feeding behaviour; Selection efficiency; Absorption efficiency; Net energy balance.
Ano: 1996
URL: http://archimer.ifremer.fr/doc/00040/15080/12419.pdf

Management of oyster and mussel culture
Provedor de dados: 5
Autores: Heral, Maurice; Drinkwaard, A.; Bohle, B.; Figueras, Antonio; Lavoie, R.; Maurer, Daniele.
The world aquaculture production (fresh and marine waters) achieved 11.1 million tonnes in 1986 (FAO, 1989). The molluscs represented 21 % of the total production. Marine aquaculture with 5.45 million tonnes reached 49% of the total production. The marine cultivated mollusc production was 2.25 million tonnes due mainly to oysters (36%), mussels (34%), clams (16%), and scallops (6%).  As the aquaculture production is clearly identified in the statistics only since 1984, the evolution of the production of oysters and mussels for the last 15 years has been analyzed with the FAO data for the total catch (fisheries and culture). By comparison of the two statistics for the same year (1986), the fisheries represented only 17% for oysters and 16% for mussels. Fig....
Tipo: Text
Palavras-chave: Culture; Mussels; Oysters; Panel report.
Ano: 1990
URL: http://archimer.ifremer.fr/doc/1990/publication-3020.pdf

Analyse historique de la production conchylicole du Bassin de Marennes-Oléron et essai d'estimation empirique du potentiel conchylicole
Provedor de dados: 5
Autores: Heral, Maurice; Deslous-paoli, Jean-marc.
The analysis of the official statistics of commercialised production of oysters (.Crassostrea angutata and Crassostrea gigas ) is achieved from 1866 to 1984 in term of their numbers and weights for the bay of Marennes-Oleron. The number of sanitary labels, multiplied by the mean weight of a crate can also give out the commercialised production   provided it is increased by the bias and decreased by the exterior production of the bay . Thus the production of Portuguese oysters is only 45 000 tons from 1948 to 1957 with a  maximum of 52, 000 tons for respectively 70 000 tons and 280 000 tons for the statistics . AIso, after the epizooties of Crassostrea angulata the production, fell down to 25 000 tons in 1971 according to the number of sanitary labels...
Tipo: Text
Palavras-chave: Crassostrea gigas; Production conchylicole; Analyse statistique.
Ano: 1985
URL: http://archimer.ifremer.fr/doc/0985/acte-2958.pdf

La capacité biotique des bassins ostréicoles
Provedor de dados: 5
Autores: Heral, Maurice; Bacher, Cedric; Deslous-paoli, Jean-marc.
Maurice Héral has been studying, since 1976 at the IFREMER Station of La Tremblade (France), the trophic networks of shellfish-farming ecosystems and, especially, the variability of available food, energy assessment, the ecophysiology of the Japanese oyster; he has set up a comprehensive model of shellfish farming production. He has been managing the Shellfish Farming Ecosystems Laboratory (LEC) since 1980. A specialist of digital models, Cédric Bacher has been working at the LEC since 1985. He invented a strategy of sampling farmed molluscs' biomass and a preliminary, analytic trophic model that combines physical and biological systems. Jean-Marc Deslous-Paoli has been a member of the same laboratory since 1979, where his work focuses on monitoring...
Tipo: Text
Palavras-chave: Modèle analytique; Modélisation; Modéle global; Production; Capacité trophique; Biomasse; Climatologie; Captage naissain; Bassin Marennes Oléron.
Ano: 1989
URL: http://archimer.ifremer.fr/doc/1989/publication-3011.pdf

Combined effects of temperature-salinity on larval survival of the Eastern oyster Crassostrea virginica in the Maryland portion of the Chesapeak Bay (USA)
Provedor de dados: 5
Autores: Goulletquer, Philippe; Heral, Maurice; Prou, Jean.
Oyster landings in the Maryland portion of the Chesapeake Bay have declined by more than 50fold since the early part of the century, despite intensive management efforts. The annual shell repletion program is the most critical programmatic element to effect recovery of the ailing Eastern oyster Crassotrea virginica stock and fishery. The overall efficacy of shell repletion management depends primarily on the success of spat settlement on the planted shell, and furthermore on their survival rate. The Operations Research techniques and mathematical programming developed by Rothschild et al. (1991) attempt to maximize spat recruitment to the oyster stock subject to a series of operational constraints. Allocation and timing of shell deployment are the most...
Tipo: Text
Palavras-chave: Larval; Settlement; USA; Chesapeake Bay; Crassotrea virginica; Oysters.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/1994/publication-3074.pdf

Crepidula fornicata L. (Gastéropode, Calyptraeidae) dans le bassin de Marennes-Oléron : composition et valeur énergétique des individus et des pontes
Provedor de dados: 5
Autores: Deslous-paoli, Jean-marc; Heral, Maurice.
In the bay of Marennes-Oléron, the shell represents 60% and the dry flesh from 3 to 8.5% of the total weight of Crepidula fornicata. Seasonal changes in the biochemical composition of the dry flesh show two periods of spawning for the females and a single period of reproduction for the males, and that the main component of the energy reserve is glycogen. The mean energy value of Crepidula fornicata varies between 15.1 and 19.3 joules/mg of ash-free dry weight of flesh (average 17.7) and this value is higher in the males than the females, during aIl the periods of reproduction. The females lay, as early as their third year, about 56 egg capsules at each spawning, containing a total of Il 725 eggs with an energy value of 22.4 joules/mg ash free dry weight.
Tipo: Text
Palavras-chave: Crepidula Jornicata; Composition biochimique; Valeur énergétique; Marennes-Oléron; Crepidula Jornicata; Biochemical composition; Energy value; Marennes-Oléron.
Ano: 1986
URL: http://archimer.ifremer.fr/doc/1986/publication-2964.pdf

Utilisation du filet à plancton du type "Bongo"
Provedor de dados: 5
Autores: Heral, Maurice; Woehrling, Daniel; Halgand, Daniel; Lassus, Patrick.
The "Bongo" net is an American plankton net whose use is coming into general use for studies of ichthyoplankton. Its dimensions and its power of filtration make it an efficient device for researching groups with unevenly spaced micro distribution as well as rare species, especially fish eggs and larvae. It is recommended by the ICNAF (Standard Techniques for Pelagic Fish Eggs and Larvae Surveys) and will soon be recommended by the FAO. The ISTPM, for its part, has been using this net for some years in several campaigns conducted by the Thalassa, the Cryos, La Pélagia, the Roselys and the Ichthys (ISTPM 1971, 1975, ALDEBERT 1975, ARBAULT and LACROIX 1975). In 1975, we decided to use this net in some studies in coastal waters that the ISTPM is conducting in...
Tipo: Text
Palavras-chave: Traitement échantillon; Profondeur immersion; Pêche; Echantillonneur; Filet à plancton.
Ano: 1979
URL: http://archimer.ifremer.fr/doc/1979/acte-2991.pdf

Traditional oyster culture in France
Provedor de dados: 5
Autores: Heral, Maurice.
The indigenous oyster of mainland France, the fiat oyster, Ostrea edulis has been part of the human diet for centuries. The Romans collected them and exported them to Rome. Although tanks for holding oysters after harvesting were in use at that time (GreIon 1978) it seems that true culture was not developed along the coast contrary to the records of Pliny the Older. It appears that oysters were already being captured on hoards off the Italian coast. The exploitation of natural stocks continued through the Middle Ages and the Renaissance. However, it was not until the 17th century that oyster culture began, first in the pools of the salt marshes of the Atlantic coast and then in specially managed ponds. Papy (1941) repeats a good description given in 1688...
Tipo: Text
Palavras-chave: Rearing; Diseases; Analytical model; Overall model; Cultured stocks; Energetics; Reproduction; Nutrition; Physiology; France; Culture; Oyster.
Ano: 1989
URL: http://archimer.ifremer.fr/doc/1989/publication-3039.pdf

Présélection de sites ostréicoles en pleine eau. Mise au point d'une maquette (version 0) et analyse critique. Application à la bande côtière des Pertuis Charentais
Provedor de dados: 5
Autores: Loubersac, Lionel; Guillaumont, Brigitte; Heral, Maurice; Prou, Jean; Durand, Henri.
Le présent document fait la synthèse et l'analyse critique d'une expérience préliminaire, de mise au point d'un outil et d'un produit d'aide à la décision, faisant appel aux technologies des Systèmes d'Information Géographique et visant la résolution d'un problème d'aménagement littoral. L'objectif fixé par ce travail est principalement, au travers de la réalisation d'une maquette, d'identifier les points d'ordre méthodologique qui demandent un effort de Recherche Développement. La présente étude a été conduite en partenariat entre le groupe transdirectionel SILLAGE de l'IFREMER, concepteur et architecte de la maquette du Système d'Information, et l'IFREMER DRV/RA (M. Héral et J. Prou) pour la validation scientifique du problème posé. Le groupe SILLAGE,...
Tipo: Text
Palavras-chave: Méthodologie; Ostréiculture; Système Informatique géographique; SIG; Modélisation.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/00048/15906/13334.pdf

Reproduction naturelle de Crassostrea gigas Thunberg dans le bassin de Marennes-Oleron en 1979 et 1981: Aspects biochimiques et energetiques.
Provedor de dados: 5
Autores: Deslous-paoli, Jean-marc; Heral, Maurice; Berthome, Jean-paul; Razet, Daniel; Garnier, Jacqueline.
In summer 1979, the natural reproduction of oysters Crassostrea gigas Thunberg, in Marennes-Oleron basin, produced a large number of juveniles which was not the case in summer 1981. If one compares the evolution of the main constituents of the flesh, one can see that, at the beginning of August, before spawning the male oysters in 1981 contained 6,3% less proteins, 34,2% less lipids and 61,2% less glucids than those in 1979 and respectively 12,3%, 21,3% and 69,8% less as far as females are concerned. The energetic value of ash-free dry flesh of female oysters is nearly the same for the two years whereas for male oysters the value is slightly lower in 1981 than in 1979. The total energetic values of male and female oysters show a slight difference between...
Tipo: Text
Palavras-chave: Crassostrea gigas; Seasonal variations; Food availability; Water temperature; Saccharides; Proteins; Lipids; Biochemical composition; Gametogenesis; Spawning; Sexual reproduction.
Ano: 1981
URL: http://archimer.ifremer.fr/doc/1981/publication-1891.pdf

Rapport sur les causes des mortalités d'huîtres creuses observées en juin 1992 sur le Banc de Ronce Les Bains (Bassin de Marennes-Oléron)
Provedor de dados: 5
Autores: Heral, Maurice; Bacher, Cedric; Razet, Daniel; Prou, Jean; Galgani, Francois; Renault, Tristan; Bodoy, Alain; Garnier, Jacqueline; Geairon, Philippe; Chagot, Dominique; Grizel, Henri; Comps, Michel; Masson, Daniel; Noinin, Michel.
Dès le 4 JUIN 1992, un ostréiculteur digne de confiance avait signalé aux services d'IFREMER, une situation anormale sur le banc de Ronce les Bains. Un premier prélèvement a été effectué le jour même. En effet, ce secteur avait déjà été le lieu de mortalités d'huitres estimées à 7 000 tonnes, au printemps 1988, et s'est révélé par le passé comme étant un endroit sensible. Pour information, figure en annexe le rapport établi en 1988, à destination du Préfet de la Charente Maritime. Ces mortalités ayant rapidement pris de l'ampleur, un dépôt de plainte contre X a été effectué par la Section Régionale de la Conchyliculture. A la suite de quoi, les services d'IFREMER ont été requis par la Gendarmerie Nationale (Brigade de Marennes) le 10 juin 1992, pour...
Tipo: Text
Palavras-chave: Ostréiculture; Huîtres creuses; Crassostrea gigas; Mortalité; Banc de Ronce Les Bains; Bassin de Marennes Oléron.
Ano: 1992
URL: http://archimer.ifremer.fr/doc/00048/15899/13327.pdf

Relations entre la nourriture disponible et la reproduction de mollusques en milieu estuarien : variabilité temporelle de la colonne d'eau
Provedor de dados: 5
Autores: Heral, Maurice; Deslous-paoli, Jean-marc; Prou, Jean; Razet, Daniel.
The study of the trophic relations needs to collect data which can best represent the variability of the populations of molluscan and the parameters of the water. For the water, the main parameters which play a role on the production of molluscan in an estuarine area are the temperature, the seston, and the phytoplanctonic biomass. For the temperature is proposed to sample only twice a month. At the contrary for seston variations which are very large on a tidal cycle and correlated with the currents and the waves, it is necessary to take in count this variability. For the phytoplancton, the annual cycle is well characterized, but the variability at a station is depending on the caracteristic of each water masses. The authors suggest that a sampling...
Tipo: Text
Palavras-chave: Estuarine ecosystem; Trophic relationships; Time variations; Sampling strategies; Ecosystème estuarien; Relations trophiques; Variabilité temporelle; Stratégie d'échantillonnage.
Ano: 1987
URL: http://archimer.ifremer.fr/doc/1987/publication-2868.pdf

Effect of orgnotin compounds (TBT) used in antifouling paints on cultured marine molluscs - a literature study
Provedor de dados: 5
Autores: Heral, Maurice; Alzieu, Claude; Deslous-paoli, Jean-marc.
Organotin salts, used as antifouling substances have a deleterious effect on the environment particularly on molluscs and especially on the Japanese oyster Crassostrea gigas. A synthesis of the effects of tributyltin (TBT) on cultured molluscs reveals the following effects: 1) acute and chronic toxicity to the adults; 2) accumulation in the flesh 01 the adults; 3) perturbation 01 reproduction particularly fertility, mortality 01 offspring and decrease in larval growth rate; 4) decrease in the growth rate 01 juveniles and thickening 01 the shell; and 5) modification 01 the physiology al sublethal levels.
Tipo: Text
Palavras-chave: TBT; Crassostrea gigas; Oyster; Marine molluscs; Organotin.
Ano: 1989
URL: http://archimer.ifremer.fr/doc/1989/publication-3016.pdf

Dynamiques des productions et des biomasses des huîtres creuses cultivées (Crassostrea angulata et Crassostrea gigas) dans le bassin de Marennes-Oléron depuis un siècle
Provedor de dados: 5
Autores: Heral, Maurice; Deslous-paoli, Jean-marc; Prou, Jean.
The evolution of the production of cupped oysters is estimated on a century (1885-1985) with three different sources of data. The total biomass in culture is calculated from productions by knowing regularly the growing rate and the mortality rate of the populations of oysters. It appears that the efficiencies of the culture (P/B) decrease when the stock increase. The production reaches a plateau maximum of 40 000 tons whereas the stock goes on to growth up to 200 000 tons. This plateau correspond to the maximal capacity of production of the ecosystem limited by the trophic capacities of the bay. This work shows that without management of the cultivated oysters, the stocks tend to exceed the minimal biomass which is necessary to reach the maximal potential...
Tipo: Text
Palavras-chave: Biomasse; Marennes Oléron; Huîtres; Crassostrea angulata; Crassostrea gigas.
Ano: 1986
URL: http://archimer.ifremer.fr/doc/1986/acte-2965.pdf

Incidence de la diminution des débits de la Charente sur la production primaire du bassin de Marennes-Oléron
Provedor de dados: 5
Autores: Ravail, Brigitte; Heral, Maurice; Razet, Daniel; Robert, Jean-michel.
Le suivi bi-mensuel des caractéristiques des eaux de l'estuaire de la Charente met en évidence les fortes teneurs en sels nutritifs transportés par ce fleuve. Les apports de fin d'hiver en nitrates sont supérieurs à 240 µ atg N 1(1). Le phosphore a un comportement particulier puisqu'en période de crue, il s'adsorbe sur les particules et le sédiment, jouant un effet régulateur, ainsi les aports ne dépassent guère 2 µ atg P 1(1) en hiver mais aussi en été. Les biomasses phytoplanctoniques vivantes ou dégénérescentes sont fortes avec deux périodes defflorescence bien marquées, mai-juin et octobre. Les teneurs en chlorophylle a atteignent è µg de chla pour la surface et 23 µgde chla pour le fond. Par ailleurs, les teneurs en phéopigments dépassent 31 µg de...
Tipo: Text
Ano: 1986
URL: http://archimer.ifremer.fr/doc/00390/50177/50798.pdf

Incidence du débit de la Charente sur la capacité biotique du bassin ostréicole de Marennes-Oléron
Provedor de dados: 5
Autores: Ravail, Brigitte; Heral, Maurice; Maestrini, Serge; Robert, Jean-michel.
The estuary of Charente can be considred as a vast natural zone of mixing brackish waters and marine waters of Marennes-Oleron. One part of the cruises engaged from October 1985 to November 1987, allowed to dfine the main hydrobiological features of the estuary and to estime the input of the river Charente. Cruises permitted to establish the general hydrobiological schema of the estuarine bay and showed that the river Charente does play a part in the salinity and nitrogen inputs on marine waters.
Tipo: Text
Palavras-chave: Estuaire; Charente; Marennes-Oléron; Panache de dispersion; Eaux douce; Impact.
Ano: 1988
URL: http://archimer.ifremer.fr/doc/00015/12663/9552.pdf

Approches de la capacité trophique des écosystèmes conchylicoles : synthèse bibliographique
Provedor de dados: 5
Autores: Heral, Maurice.
The different methods of estimating the trophic capacity of ecosystems cultivated by oyster farming and mussel farming are introduced by ascending order of complexity. Thus, production yields make it possible to monitor whether the size of the farmed stock is being successfully matched with the availability of food. Moreover, the study of annual production farmed stocks has made it possible to create comprehensive dynamic models that show the maximum annual production that a given ecosystem can support. These last two approaches assume the environment to be constant. The study of trophic links that can simulate growth performance of molluscs can be classified according to two criteria, (i) their level of complexity in combining biology and physics, (ii)...
Tipo: Text
Palavras-chave: Ecosystèmes conchylicoles; Conchyliculture; Capacité trophique.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/1991/publication-3052.pdf

Difficulties in sampling for estimation of phytoplankton biomass in estuarine conditions : variabilities and precisions at different temporal scales in the case of the bay Marennes Oleron
Provedor de dados: 5
Autores: Heral, Maurice; Goulletquer, Philippe; Razet, Daniel; Prou, Jean; Ravail, Brigitte; Maestrini, Serge.
Different sampling strategies have been tested for estimation of phytoplanktonic biomasses in a bay submitted to estuarine conditions and high velocity of currents. Daily variations showed that for a precision of 5% of the daily mean, it is necessary to sample with a 1 hour and a half time scale. Systematic sampling appears to be more preceise than the random sampling. A sampling during 35 days at low tide and at high tide, during the phytoplanktonic bloom, showed the large variability between the days. A precision of 30% of the mean biomass of the month is obtained with a 8 days time scale. Comparison between tidal cycle sampling (10% of precision) with a punctual sample in the middle of the day did not show large differences. As the main variability is...
Tipo: Text
Palavras-chave: Marennes Oleron; Phytoplanktonic biomasses; Estimation.
Ano: 1988
URL: http://archimer.ifremer.fr/doc/1988/acte-2877.pdf

Effet des biodépôts de l'huître Crassostrea gigas (Thunberg) sur l'accumulation de matières organiques dans les parcs du bassin de Marennes-Oléron
Provedor de dados: 5
Autores: Sornin, Jean-marc; Feuillet, Michelle; Heral, Maurice; Deslous-paoli, Jean-marc.
The accumulation of biodeposits brings about geochemical modifications of the underlying sediment, that are noticeable. The increase can reach 83% of the amount of organic carbon. By catching the deposits on the spot and by gathering them directly from the oyster tables we get a daily deposit that can weigh, according to season, between 8 and 99 g of carbon a square meter. The recycling of important quantities of organic matter increase the oxygen needs and the most reducing environment provides opportunities for ammonification and reduction of sulfate into sulfur. So we can consider that there is as much as 4 times more sulfurous hydrogen in intensive oyster-growing areas. This output of sulfurs seems to cause the oyster filtration some damage (Ito et...
Tipo: Text
Palavras-chave: Marennes Oleron; Sediment; Oysters; Physiology; Filtration; Biodeposits; Crassostrea gigas; Marennes Oléron; Sédiment; Huître; Physilogie; Filtration; Biodépôts; Crassostrea gigas.
Ano: 1983
URL: http://archimer.ifremer.fr/doc/1983/acte-2955.pdf

Etude de la biomasse bactérienne dans le bassin de Marennes-Oléron
Provedor de dados: 5
Autores: Heral, Maurice; Prou, Jean.
A seasonal study of total microflore shows that heterotrophic germs are submitted to a distinctive evolution in autumn and winter suspension and degradation of detritic material; in spring an summer bacterial growth due to degradation of phytoplanction. In summer enterocoques give evidence of positive summer pollution. Survival on the mud of Escherichia coli and overall of enterocoques indicates that the substration is particularly suitable to germ proliferation;
Tipo: Text
Palavras-chave: Marennes Oléron; Escherichia coli; Bactériologie; Biomasse.
Ano: 1980
URL: http://archimer.ifremer.fr/doc/1980/acte-3005.pdf

Valeurs caloriques de la chair de l'huître Crassostrea gigas Thumberg : estimation directe et biochimique
Provedor de dados: 5
Autores: Deslous-paoli, Jean-marc; Heral, Maurice.
Caloric values of the ash-free dried sofkt parts of Crassostrea gigas have been characterized, according to season using a microcalorimeter and biochemical composition. This study shows the difference between the two methods. A conversation factor (8,63 kcal-gr(-1) has been determined for lipid of pacific oyster. Thix work shows that reproduction implies a loss of energy (53% to 63%) for non juvenile oysters. The increase of energetic level necessary to growth is more important for juvenile oysters and is upper than what is lost for reproduction.
Tipo: Text
Palavras-chave: Lipid; Energetic level; Crassostrea gigas; Oysters; Lipide; Teneur énergétique; Crassostrea gigas; Huîtres.
Ano: 1980
URL: http://archimer.ifremer.fr/doc/1980/acte-3162.pdf

Etudes préliminaires des potentialités nutritives dans le bassin de Marennes-Oléron
Provedor de dados: 5
Autores: Heral, Maurice.
Various methods are briefly described for the study of an oyster population from the point of view of energy : biomass, growth mortality, reproduction and respiration. The oyster population is observed in its ecosystem, and every food source of the oyster is described, along with the means of study that are put into practice. The numerous competitions with oysters are mentioned as that they can be taken into account in further studies
Tipo: Text
Palavras-chave: Marennes Oléron; Mortalité; Croissance; Biomasse; Bilan énergétique; Crassostrea gigas; Huîtres.
Ano: 1977
URL: http://archimer.ifremer.fr/doc/1977/acte-6259.pdf

Report of the workshop on shellfish bivalve cultivation, growth, modelling and impact on the ecosystem
Provedor de dados: 5
Autores: Heral, Maurice; Bayne, B.
The Workshop was held in Plymouth (6-10 October 1996) in the Royal Plymouth Corinthian Yacht club organised by the Plymouth Marine Laboratory under the joint charmanships of B. Bayne et M. Héral. 36 scientists were participated to this meeting from 11 countries, 8 belonging to ICES (Annex 1) 30 communications have been presented. This meeting was supported by an European Union contrat from DG14 with a concerted action AIR3 CT 942219 on Trophic capacity of coastal zone of oysters, mussels and cockles cultivation. This contract has paid the travel cost of all the participants.
Tipo: Text
Palavras-chave: Coastal systems; Carrying capacity; Physiological results; Oyster; Shefflish bivalve.
Ano: 1996
URL: http://archimer.ifremer.fr/doc/1996/acte-7350.pdf

Oyster culture in European countries
Provedor de dados: 5
Autores: Heral, Maurice; Deslous-paoli, Jean-marc.
Three species of oysters have been or are cultivated in Europe: Crassostrea angulata, C. gigas, and Ostrea edulis. If we follow the taxonomic critera of Grassé,  the European oysters belong to the group of Mollusca, class of Lamellibranchia or Bivalves, order of Filibranchia, family Ostreidae with two genera: C. angulata (Lamarck), Portuguese, cupped oyster; C. gigas, (Thunberg), Japanese or Pacific, cupped oyster; Ostrea edulis (Linné), fiat European oyster.  Some authors think that C. gigas and C. angulata belong to the same species. lndeed, Ranson stated that the characteristics of the larvae are the same, and Menzel obtained viable hybrids (F2) between these two oysters. AIso, Buroker et al. in studying the genetic variations of proteins and enzymes of...
Tipo: Text
Palavras-chave: European countries; Pathology; Methods of culture; Recruitment; Fishery; Salinity and temperature tolerances; Larval development; Growh; Biology; Oyster culture.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/1991/publication-3038.pdf

Programme Charente-Marennes-Oléron Volet Maritime
Provedor de dados: 5
Autores: Heral, Maurice; Bacher, Cedric; Razet, Daniel; Prou, Jean; Deslous-paoli, Jean-marc; De Pontual, Helene; Raillard, Olivier; Maestrini, Serge; Mornet, Francoise; Menesguen, Alain; Sautour, Benoit; Robert, Jean-michel.
Les termes du contrat passé entre le Fond de la Recherche et de la Technologie et l'IFREMER précisent qu ele programmer a pour objectif une gestion rationnelle du milieu conchylicole avec notamment une mise au point de modèles (voir notification de l'aide en annexe). Un premier modèle appelé modèle global par analogie avec les modèles de pêche met en évidence la limite de la capacité trophique du bassin de Marennes-Oléron pour les huîtres cultivées. Un modèle analytique avec un modèle physique simple permet dans un premier temps de développer un modèle de croissance des huîtres en fonction de la nourriture disponible et d'effectuer des simulations qui confirment l'influence du stock sur les performances de croissance des bivalves. Un troisième approche...
Tipo: Text
Palavras-chave: Modèle production; Biomasse; Huître creuse; Crassostrea gigas; Modèle énergétique; Croissance; Modèle multiboîte; Marennes Oléron; Modèle trophique; Marennes Oléron.
Ano: 1986
URL: http://archimer.ifremer.fr/doc/00048/15908/13337.pdf

Etude hydrobiologique du bassin de Marennes-Oleron. Un exemple: la secheresse de l'ete 1976.
Provedor de dados: 5
Autores: Heral, Maurice; Berthome, Jean-paul; Razet, Daniel; Garnier, Jacqueline.
Consequences of drought during the summer of 1976 are related. Principal component analysis allowed the division of the area into 5 main districts, each of them with distinctive hydrological and phytoplanktonic characteristics. The rivers Charente and Seudre are particularly eutrophic and carry great quantities of nitrates, phosphates and silicates. Eutrophic evaluation of the river Seudre is studied, as well as oyster mortalities that resulted. Reproduction and settlement of spat oysters are related to the hydrology of each district.
Tipo: Text
Palavras-chave: France; Charente R. Oyster culture Environmental effects Eutrophication Droughts.
Ano: 1978
URL: http://archimer.ifremer.fr/doc/1978/publication-1958.pdf

Influence des facteurs climatiques sur la production conchylicole du bassin de Marennes-Oléron
Provedor de dados: 5
Autores: Heral, Maurice; Prou, Jean; Deslous-paoli, Jean-marc.
The authors are comparing the recruitment, the commercialised production, the cultivated biomasses of oysters Crassostrea gigas and Crassostrea angulata  with the statistics of the meteorology (1885-1984). The temperature plays a role up on the date of spawning but partialy explains the lack of recruitment, which has less impact on the commercialised production than on the total biomass. The annual and seasonal characteristics of the precipitations and water temperatures do not show tight correlations with the variations of the production and of the biomass, for these cultivated populations in opposition with the sensitivity of the natural molluscan populations towards the climatic factors.
Tipo: Text
Palavras-chave: Meteorology; Recruitment; Biomass; Production; Crassostrea angulata; Crassostrea gigas; Météorlogie; Recrutement; Biomasse; Production; Crassostrea gigas; Crassostrea angulata.
Ano: 1986
URL: http://archimer.ifremer.fr/doc/1986/publication-2968.pdf

Composition de la matière organique particulaire dans les eaux du bassin de Marennes-Oléron : apport énergétique pour la nutrition de l'huître
Provedor de dados: 5
Autores: Heral, Maurice; Razet, Daniel; Maestrini, Serge; Garnier, Jacqueline.
A twice monthly study shows that the major amount of organic material is from detrtic origin, and is brought in winter, when valeus of mineral seston are very high. In the sping time, phytoplancton blooms, do not make up for lack of detritic material where as in the summer, oceanic phytoplancton is composed of important amounts of carbohydrates. Available food is defined as sum of protids, lipids and carbohydrates and mesured in energetic therms. This allows to foretell the amount of food that molluscs ar likely to assimilate.
Tipo: Text
Palavras-chave: Marennes Oléron; Nutrition; Matière organique; Crassostrea gigas; Huîtres.
Ano: 1980
URL: http://archimer.ifremer.fr/doc/1980/acte-3003.pdf

Effets d'enrichissements azotés sur la croissance des palourdes mises en élevage dans les claires du bassin de Marennes-Oléron
Provedor de dados: 5
Autores: Goulletquer, Philippe; Razet, Daniel; Prou, Jean; Garnier, Jacqueline; Taillade, Sylvie; Heral, Maurice; Peyre, R; Faivre, C.
Etant donné que la production de mollusques (palourdes ou huîtres) est limitée à 0,8 kg à 1 kg au m2 soit 40 à 50 palourdes adultes de 20 g au m2, il est intéressant d'essayer de forcer cette production en augmentant la production primaire qui est le facteur limitant de la production de palourdes. Cette production primaire dépend des apports en sels nutritifs en effet les travaux antérieurs de Zanette (1979), de Zanette et Garnier (1980), de Robert (1984) ont mis en évidence que les biomasses phytoplanctoniques ne peuvent dépasser un certain seuil à cause de l'épuisement progressif en sels nutritifs. Robert et al. (1984) ont mis en évidence, dans les claires de la Baie de Bourgneuf que l'azote est le premier facteur limitant de la croissance...
Tipo: Text
Ano: 1985
URL: http://archimer.ifremer.fr/doc/00389/50053/50641.pdf

Etude de la faisabilité d'élevages d'huîtres en eau profonde dans le Pertuis Charentais
Provedor de dados: 5
Autores: Heral, Maurice.
Le bassin de Marennes-Oléron, premier bassin ostréicole français est une baie chroniquement en surcharge. Les déficits de croissance et l'accroissement des mortalités non liées à des pathogènes se sont accentués parallèlement aux anomalies climatiques. Les 3 années de sécheresse (1989-1992) ont montré la grande dépendance pour la productivité de cet écosystème, aux apports d'eau douce estivaux, d'où les conflits pour l'usage de l'eau qui sont apparus. Sur le cheptel affaibli du bassin de Marennes-Oléron en 1993 a été identifiée une chlamydie-like qui altère les branchies des huîtres et qui devrait être un élément supplémentaire de fragilisation du cheptel. La conchyliculture en Charente-Maritime regroupe 4 500 conchyliculteurs qui exploitent 2 800...
Tipo: Text
Palavras-chave: Etude de site; Ostréiculture; Eau profonde; Zone de Culture; Huîtres creuses; Crassostrea gigas.
Ano: 1993
URL: http://archimer.ifremer.fr/doc/00048/15900/13328.pdf

La sécheresse de l'été 1976 dans le bassin ostréicole de Marennes-Oléron : aspects hydrobiologiques
Provedor de dados: 5
Autores: Heral, Maurice; Berthome, Jean-paul; Razet, Daniel; Garnier, Jacqueline.
Consequences of drought and canicule during the summer of 1976 are related. An analysis allow as to mark out five main districts : Charente, Seudre, North, South and Center of the bassin, each of them with distinctive hydrological and phytoplaktonic characteristics. The rivers Charente and Seudre are particulary eutrophic and any great quantities of nitrates, phosphates and silicates. Eutrophic evaluation of the river Seudre is studied, as well as oyster mortalities that resulted. Reproduction and settlement of spat oysters are related to the hydrology of each distric.
Tipo: Text
Palavras-chave: Ostréiculture; Impact; Sécheresse; Bassin Marennes Oléron; Canicule.
Ano: 1977
URL: http://archimer.ifremer.fr/doc/1977/acte-2994.pdf

Anomalies de croissance de la coquille de Crassostrea gigas dans le bassin de Marennes -Oléron. Bilan de toris années d'observation
Provedor de dados: 5
Autores: Heral, Maurice; Berthome, Jean-paul; Polanco Torres, E.; Alzieu, Claude; Deslous-paoli, Jean-marc; Razet, Daniel; Garnier, Jacqueline.
The appearance and changes of the oyster shell's gelatinous bags have been monitored since 1979. The increase in thickness that causes the growth into a "ball" can be explained by an overproduction of gel. The various environmental factors that can intervene in the secretion of gel are successively examined.
Tipo: Text
Palavras-chave: Oysters; Shell; Crassostrea gigas; Huîtres; Coquille; Crassostrea gigas.
Ano: 1981
URL: http://archimer.ifremer.fr/doc/1981/acte-2943.pdf

Facteurs contrôlant la croissance de Ruditapes philippinarum dans 4 nurseries de production en Charente-Maritime (France)
Provedor de dados: 5
Autores: Heral, Maurice; Deslous-paoli, Jean-marc; Garnier, Jacqueline; Prioul, Daniel; Heurtebise, Serge; Razet, Daniel.
Different types of pregrowth of the Japanese palourde are compared on the some site. The method by upwelling which is the more common used, to have good growth, requires a compromise between the running and the raised biomass.  Two periods are critical, in the summer the growth of mollusks is stopped because of a decrease in the phytoplanktonic production ;  in the winter, a fall in temperature lessens filtration and stops growth. The results concern clams consummatation rates of particular food (chlorophyll, protids, lipids, glucids) as weIl as the way to supply the decreasing growth : increase of phytoplankyonic production in the summer by recycling waters from nurseries that are loaded with ammoniac and raise winter temperatures by using under-ground...
Tipo: Text
Palavras-chave: Nursery; Growth; Ruditapes philippinarum; Clams; Nurserie; Croissance; Ruditapes philippinarum; Palourdes.
Ano: 1982
URL: http://archimer.ifremer.fr/doc/1982/acte-2951.pdf

La Charente, un estuaire conchylicole
Provedor de dados: 5
Autores: Thomas, Gerard; Kantin, Roger; Heral, Maurice.
A coastal river 380 km long, the Charente river has a catchment area of about 10,000 km2, flowing through the departments of Charente and Charente-Maritime, as well as a small part of the border departments: Dordogne, Deux-Sèvres, Haute-Vienne and Vienne. Its main affluents are the Tardoire, the Seugne and the Boutonne rivers. The highest part of the catchment area is located in Dordogne, at a height of 496 m, whereas the river itself originates from a spring located at a height of 250 m to the south-east of Rochechouart, in the Haute-Vienne. The average height of the catchment area is quite low. In its downstream part, from the Saint-Savinien dam to the ocean, the Charente is influenced by a dynamic tide. The actual estuarine part begins in...
Tipo: Text
Palavras-chave: Charente Maritime; Gestion eau; Qualité eaux; Conchyliculture; Capacité trophique; La Charente; Estuaire.
Ano: 1999
URL: http://archimer.ifremer.fr/doc/1999/publication-6289.PDF

Modelling growth and feeding of the Japanese oyster Crassostrea gigas in Marennes-Oleron Bay (France)
Provedor de dados: 5
Autores: Raillard, Olivier; Deslous Paoli, Jean-marc; Heral, Maurice; Razet, Daniel.
A model simulating growth and feeding is presented for Crassostrea gigas and incorporates such physiological processes as filtration rate, pseudo-faeces production and ingestion, oxygen consumption and spawning. The only state variable is flesh weight. This model is designed to incorporate the effects of quantity and quality of food, temperature and oyster dry weight. Comparison of simulation outputs with real data showed that the model closely simulated the seasonal changes in weight over a two-year sample interval. This simulation confirms that oyster growth in Marennes-Oleron Bay is strongly regulated by the non-organic concentration in the seston. This latter factor dilutes the potential food for oyster and causes a large amount of food rejection in...
Tipo: Text
Palavras-chave: MODEL; ENERGETIC BUDGET; GROWTH; TURBIDITY; CRASSOSTREA-GIGAS.
Ano: 1993
URL: http://archimer.ifremer.fr/doc/1993/publication-3066.pdf

A methology for the stocks assessments of cultivated oysters among along the French Atlantic coasts
Provedor de dados: 5
Autores: Bacher, Cedric; Baud, Jean-pierre; Bodoy, Alain; Deslous-paoli, Jean-marc; Dreno, Jean-paul; Heral, Maurice; Maurer, Daniele; Prou, Jean.
An assessment of the reared stocks of the Pacific oyster (Crassostrea gigas ) has been recently conducted on the major French areas of molluscs culture. The methodology proposed included both estimates of densities obtained by subsampling in the field, and aerial photographs which covered the cultivated, intertidal area. The size and the number of samples were designed to reach a precision of 10% on the final assessment in each area. The field work consisted in weighing and counting the oyster in unit areas of 0.5 m2 for the bottom culture or in trays or bags, for the off bottom technique. These results give a better knowledge of the technique evolution and of the general structures in the cultivated areas.
Tipo: Text
Palavras-chave: Modeling; Estimation; Stocks; Crassostrea gigas; Oysters.
Ano: 1986
URL: http://archimer.ifremer.fr/doc/1986/acte-2864.pdf

Les dosages de calcium : méthodes et intercalibrations
Provedor de dados: 5
Autores: Heral, Maurice; Feuillet, Michèle; Razet, Daniel.
Les dosages du calcium dissous dans l'eau du bassin de Marennes-Oléron ont mis en évidence un déficit calcique supérieur à 30% en hiver. En mai, période de forte pousse de la coquille de l'huître, on a constaté en certain secteur du bassin que 70% du calcium est consommé. Le dosage du calcium s'est de plus révélé très utile pour dégrossir les problèmes de malformations de coquilles et pour les relier avec les défauts de calcifications et avec l'apparition de poches gélatineuses. C'est pour ces raisons que nous avons étudiés les différentes méthodes de dosages du calcium et organisé une intercalibration.
Tipo: Text
Ano: 1980
URL: http://archimer.ifremer.fr/doc/00388/49886/50447.pdf

Pearl oysters in French Polynesia
Provedor de dados: 5
Autores: Heral, Maurice.
Tipo: Text
Ano: 2001
URL: http://archimer.ifremer.fr/doc/00183/29433/27808.pdf

Influence de la charge particulaire sur la filtration d'une population d'huître Crassostrea gigas dans le bassin estuarien de Marennes-Oléron (France) : analyse de deux cycle de marée
Provedor de dados: 5
Autores: Soletchnik, Patrick; Prou, Jean; Heral, Maurice; Barille, Laurent; Razet, Daniel; Guezennec, Loïc.
Filtration of oyster population (100 animals) have been followed during 16 days in raceway systems with continuous recorder of the input and output of the raceway for in situ turbidity and fluorescence. Experimental conditions were fluctuated with particulate matter which varied during a tidal cycle from 40 mg.l-1to 300 mg.l-1. During the same period the phytoplanktonic biomass presented synchronous variations form 7 to 20 µg.l-1 bound with sediment resuspension of phytobenthos and oyster biodeposit created by alternating currents. Filtration of oyster population during a neap tide cycle, variated between 1.2 and 2.8I.h-1 by animal for a calculated retention based on turbidity and between 2.4 and 4.8 l.h-1 by animal for a retention calculated with...
Tipo: Text
Palavras-chave: Marée; Charge particulaire; Marennes Oléron; Physiologie; Filtration; Crassostrea gigas; Huîtres.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/1991/acte-3059.pdf

Extension des apports solides et liquides d'origine estuarienne dans les eaux de surface du plateau Aquitain interne.
Provedor de dados: 5
Autores: Jouanneau, J.-m.; Berger, P; Boutier, Bernard; Ewald, M; Fontugne, M; Heral, Maurice.
The PLACAR cruise, which took place after the first autumn floodings on the inner Aquitaine shelf, permitted to determine the outspread of solid and liquid inputs originating from the Gironde in superficial waters. In addition to the classical evaluations (S. ppt., P.O.C., nutritive salt) and S.E.M. observations, the researchers carried out detailed analyses of D.O.C., isotopic composition of P.O.C. delta super(13)C, dissolved fulvic acids and metals.
Tipo: Text
Palavras-chave: Biscay Bay ANE; France Salts Salinity Water temperature Suspended organic matter Estuarine dynamics.
Ano: 1983
URL: http://archimer.ifremer.fr/doc/1983/publication-1830.pdf

Evaluation of the carrying capacity of molluscan shellfish ecosystems
Provedor de dados: 5
Autores: Heral, Maurice.
Growth of molluscs raised in coastal zones, where the water exchange rate is low, appears to be limited, once a certain biomass level is attained, by the availability of food, making it necessary to determine as accurately as possible the trophic capacity of an ecosystem. This paper analyses the various sources of food for molluscs. It would appear that dissolved organic substances play a major role, providing up to half the energy necessary for their metabolism. Particulate material is filtered by molluscs in proportion to their size, with optimum filtration rates varying with species. The negative effect on meat production of high mineraI seston rates is demonstrated, and an analysis provided of the respective role of each component of organic matter....
Tipo: Text
Palavras-chave: Evaluation; Carrying capacity; Molluscs; Ecosystems; Cochyliculture; Ecosytemes; Molluscs; Evaluation; Capacité biotique.
Ano: 1985
URL: http://archimer.ifremer.fr/doc/1985/acte-2945.pdf

Premières approches de la composition de la nourriture organique particulaire de Crassotrea gigas dans les eaux du bassin de Marennes-Oléron
Provedor de dados: 5
Autores: Heral, Maurice; Razet, Daniel.
A seasonal study shows that bath rivers Charent.e and Seudre play an important part by carrying a great quantity of fresh water phytoplankton and vegetal detritus, along with mineraI material as a result,  the amount of pheopigments is very important and appears to be added with the feces of the oyster. The values of chlorophyll a and A T P are high in May and October but they appear to have no correlation. The high values of proteins mean a synthesis between living organic material and dead material which represent the whole amont of nutritive potential for oysters
Tipo: Text
Palavras-chave: Marennes Oléron; Nourriture organique particulaire; Crassostrea gigas; Huîtres.
Ano: 1977
URL: http://archimer.ifremer.fr/doc/1977/acte-2993.pdf

Gestion des écosystèmes conchylicoles : le cas des pertuis charentais
Provedor de dados: 5
Autores: Goulletquer, Philippe; Heral, Maurice.
The nutritional capacity of an oyster culture basin relies on the nutrient input, as well as the hydrodynamic which conditions the time of residence of the masses of water enabling the development of the phytoplankton. This limited amount of food has to be shared between the different natural populations and the cultivated ones (oysters or mussels). The total amount of these biomasses has to be controlled so as not to exceed the capacity limit.
Tipo: Text
Palavras-chave: Biomasse; Capacité nutritionnelle; Conchyliculture; Charente Martime; Pertuis charentais; Ecosystème.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/acte-3515.pdf

Acquisition de donnée en continu sur la matière particulaire de la Baie estuarienne de Marennes-Oléron pendant le bloom printaniter planctonique : effet sur le taux de filtration de l'huître Crassostrea gigas
Provedor de dados: 5
Autores: Heral, Maurice; Razet, Daniel; Prou, Jean.
The continuous obtention of different signals has been achieved for 9 days at a -fixed station during May 1988. The speed and direction of the currents have been monitoring concurrently with "in situ" turbidity and fluorescence in relation with the meteorological conditions. The concentration in particulate matter and the planktonic fluorescence fluctuated in direct relation with the water depth, the speed of the current and with the origin of the water masses. The oysters submitted to these large fluctuated conditions showed not constant filtration rate. The filtration calculated by turbidimeters (2 1 h-l g-1 dry weight) was three time less than the one achieved with fluorimeters (61 h-l g-1 dry weight). The filtration rate were fluctuated but not in...
Tipo: Text
Palavras-chave: France; Marennes Oleron bay; Acquirring of continous data; Filtration; Crassostrea gigas; Particular matter; Marennes Oléron; Aquisition données; Courantologie; Filtration; Crassostrea gigas; Matière particulaire.
Ano: 1989
URL: http://archimer.ifremer.fr/doc/1989/acte-3021.pdf

Etudes des bases génétiques et de la varibailité des caractères physiologiques impliqués dans la croissance chez l'huître creuse Crassostrea gigas
Provedor de dados: 5
Autores: Collet, Bertrand; Boudry, Pierre; Bougrier, Serge; Heurtebise, Serge; Phelipot, Pascal; Ledu, Christophe; Morand, Berenice; Heral, Maurice; Gerard, Andre.
A European programme (GENEPHYS) was launched in 1996 to study the genetic basis and variability of physiological characters involved in growth in Crassostrea gigas. This research programme was a prerequisite for any genetic selection programme on physiological functions. Research groups from Ireland, England, Greece and France are involved in this project and participate in genetic analyses (allozymes and microsatellites) and physiological analyses (ecophysiology, enzymology, stress proteins). Ifremer at La Tremblade was responsible for producing the biological material while Ifremer-CREMA (human-influenced marine ecosystems research centre) was responsible for carrying out non-destructive physiological analyses.
Tipo: Text
Palavras-chave: Sélection génétique; Croissance; Crassostrea gias; Génétique.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/1997/acte-3243.pdf

Rapport d'activité 1990 de l'Unité de Recherche Ecosystèmes Aquacoles (UREA) La Tremblade
Provedor de dados: 5
Autores: Heral, Maurice.
Rapport d'activités 1990 de l'Unité de Recherche Ecosystèmes Aquacoles (UREA) La Tremblade
Tipo: Text
Palavras-chave: Aquaculture; Conchyliculture; Croissance; Biochimie; Estimation biomasse; Hydrobiologie; Modélisation; Bassin de Marennes Oléron.
Ano: 1990
URL: http://archimer.ifremer.fr/doc/00072/18281/15851.pdf

La matière organique particulaire dans les eaux du bassin de Marennes-Oléron et de ses marais adjacents (claires) : conséquences pour la nutrition de l'huître Crassostrea gigas
Provedor de dados: 5
Autores: Heral, Maurice; Zanette, Yvan; Deslous-paoli, Jean-marc; Robert, Jean-michel; Razet, Daniel.
In 1979 and 1980, the characteristics of the particulate organic matter are defined fortnightly through seston analyses. It is very high in the basin and very low in the finishing ponds. The phytoplanktonic biomasses are maximal in May in the estuary, and in June-July in the finishing ponds, with chlorophyll contents 10 times higher than those monitored in the basin. Proteins are generally the main biochemical components found in both environments, with glucids accounting for 20 % and lipids for only 10 % of the biochemical components on average. The C/N ratios are almost constant in the finishing ponds with values around 5, typical of phytoplankton, whereas they are very high in the basin except in spring. In the same way, the protid/chlorophyll and the...
Tipo: Text
Palavras-chave: Crassostrea gigas; Huîtres; Mollusques; Qualité eau; Seston; Matière organique; Claires ostréicoles; Bassin Marennes Oléron.
Ano: 1981
URL: http://archimer.ifremer.fr/doc/1981/acte-6213.PDF

Characteristics of the particulate matter during the Mai '92 experiment. Effect on ecophysiological functions on mussel and oyster populations.
Provedor de dados: 5
Autores: Prou, Jean; Soletchnik, Patrick; Heral, Maurice; Geairon, Philippe; Razet, Daniel; Bougrier, Serge.
In order to complete the knowledge of seasonal variability of ecophysiological parameters, in situ experiment was conducted in May 1992 at the sampling site "Le Chapus". As in the previous experiments (May '91, October '91 and February '92), the race-way technique was used to study ecophysiological behavior of oyster and mussel populations submitted to natural variability.
Tipo: Text
Palavras-chave: Pacific cupped oyster; Crassotrea gigas; Particulate matter; Pigments; Particle size distribution; Retention; Filtration; Mytilus edulis.
Ano: 1992
URL: http://archimer.ifremer.fr/doc/00100/21091/18715.pdf

Water quality criteria and monitoring for marine mollusc culture : the French experience
Provedor de dados: 5
Autores: Heral, Maurice; Berthome, Jean-paul.
The impact of the main parameters of water quality which act on the life history of molluscs are presented. Two types of parameters are examined: the first are the physical-chemical parameters as temperature, salinity, turbidity, oxygen concentrations. They can be modified by perturbations directly related to human activities such as management of physical operations, e.g. constructions of dams, dredging for channels or for extraction of materials. Particular attention is given to inputs of nutrients with as consequences eutrophication and depletion of oxygen causing anoxie conditions. Attention will he focussed on some phytoplankton species like Gyrodinium aurelum which can cause mortalities in mollusc shellfish. The action of the main pollutants...
Tipo: Text
Palavras-chave: Networks; Monitoring; Water quality; Molluscs culture.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/1991/publication-3056.pdf

The measurements of nutrient fluxes at the water-sediment interface : incubation methods (in laboratory and in situ) ; gradient method (calculated fluxes) ; benthic ecosystem tunnel
Provedor de dados: 5
Autores: Feuillet-girard, Michelle; Gouleau, Dominique; Zurburg, Wouter; Small, A. C.; Dankers, N.; Heral, Maurice.
Many flux measurements methods have been described in the literature. The purpose of our study was to compare results obtained by these different methods : gradient method, incubation method (Laboratory and in situ), benthic ecosystem tunnel. The field experiment has been performed in the Marennes Oleron Bay since May 1991 (Contrat C. E. E. FAR)
Tipo: Text
Palavras-chave: Nutrient fluxes; Measurements; Methods; Incubation; Benthic ecosystem tunnel; Marennes Oleron; Charente Maritime.
Ano: 1992
URL: http://archimer.ifremer.fr/doc/00102/21304/18923.pdf

Valeur énergétique de la chair de l'huître Crassostrea gigas estimée par mesures microcalorimétriques et par dosages biochimiques
Provedor de dados: 5
Autores: Heral, Maurice; Deslous Paoli, Jean-marc.
The energetic values measured by the direct method and estimated by biochemical analysis of the annual cycle of ash-free dry weight of two Crassostrea gigas populations, show that the analytic results are inferior by 30% to those obtained by direct evaluation. The mean energetic amount is 4.84 cal.mg-1. Its seasonal variations, from 4.11 to 5.39 cal.mg-l, mainly depend on variations in the values of lipids. The mean conversion factor of lipids is 8.63 cal.mg-!, noticeably different from Brody's (9.45 caI.mg-I). This coefficient varies according to seasons from 7.85 to 9.38 cal.mg'-I. According to the biochemical evaluations, female oysters appear to he more energetic than male oysters when gonads are full. Direct evaluations, on the other hand, show no...
Tipo: Text
Palavras-chave: Crassostrea gigas; Microcalorimétrie; Biochimie; Coefficient de conversion des lipide; S Bassin de Marennes-Oléron; Crassostrea gigas; Microcalorimetry; Biochemistry; Conversion factor of lipids; Bay of Marennes-Oleron.
Ano: 1983
URL: http://archimer.ifremer.fr/doc/1983/publication-2953.pdf

Influence du cycle semi-dirune et vives-eaux mortes-eaux sur la disponibilité du matériel particulaire et son utilisation par une population de Mytilus edulis
Provedor de dados: 5
Autores: Prou, Jean; Barille, Laurent; Heral, Maurice; Ratiskol, Gilles; Soletchnik, Patrick; Bougrier, Serge; Razet, Daniel; Geairon, Philippe.
During a fortnightly tidal cycle, a Mytilus edulis population was submitted to natural food conditions in the bay of Marennes-Oléron. During 4 tidal cycles, in vivo continuous measurements of turbidity and fluorescence were recorded to study the evolution of Total Particulate Matter (TPM), phaeopigments and chlorophyll-a concentrations. Turbidity in the water column is clearly influenced by resuspension of sediment. Degradated cells of phytoplankton were associated with sediments, involving strong correlation between phaeopigments and turbidity. High values of chlorophyll-a were encountered during neap tides when turbidity was low. No relation with resuspension processes were observed.  No effect of fortnightly variability on retention was observed by...
Tipo: Text
Palavras-chave: Ancova; Utilisation du matériel particulaire; Mytilus edulis; Moules.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/1994/publication-3079.pdf

Approche de la capacite trophique d'un ecosysteme conchylicole
Provedor de dados: 5
Autores: Heral, Maurice.
The different methods for the estimation of the carrying capacity of cultivated area by oyster or mussel farming are presented gradually by order of complexity. The yield of production permit to follow if the adequation between the importance of the cultivated biomass and disponibility of food is realised. In another way, the study of the cultivated biomass and the annual production could be used for the building of global dynamic models showing the maximum of annual production that a bay can support. These approaches take for main hypothesis that the environment is constant. The study of the trophic relations for simulation of the growth rate of molluscs can be presented in function (i) of the level of complexity of the coupling between physical and...
Tipo: Text
Ano: 1989
URL: http://archimer.ifremer.fr/doc/1989/acte-2392.pdf

Essai de mise en évidence in situ de paramètres biotiques et abiotiques de l'eau et de l'interface eau-sédiment intervenant dans la production de l'huître creuse Crassostrea gigas
Provedor de dados: 5
Autores: Heral, Maurice; Deslous-paoli, Jean-marc; Razet, Daniel; Prou, Jean.
The flesh production of oysters is mainly related to concentrations of dissolved carbon and free amino acids. The younger oysters are dependent on concentrations of pheopigments while the production of the older ones is related to chlorophyll a values of the water-sediment interface. Shell production depends mainly on temperature, but also on the amount of food available: concentrations of dissolved carbon for the younger oysters and values in chlorophyll a of the interface for the older ones.
Tipo: Text
Palavras-chave: Dissolved matter; Pheopigments; Chlorophyll; Marenne Oleron estuary; Crassostrea gigas; Trophic relations; Substances dissoutes; Phéopigments; Chlorophylle a; Estuaire de Marennes Oléron; Crassostrea gigas; Relations trophiques.
Ano: 1984
URL: http://archimer.ifremer.fr/doc/1984/publication-2932.pdf

Bassin de la Charente et Baie associée de Marennes-Oléron
Provedor de dados: 5
Autores: Bacher, Cedric; Fillon, Alain; Prou, Jean; Heral, Maurice.
Les modèles d'apports de nitrates par le fleuve Charente, les modèles de productivité de production primaire et les modèles de croissance des huîtres développés précédemment ont été adaptés pour préciser l'impact de la Charente en période d'étiage sur la productivité des huîtres. L'impact de la construction éventuelle du barrage de la Charente a été évalué en fonction de son dimensionnement et de ses modalités de gestion.
Tipo: Text
Palavras-chave: Bassin de Marennes-Oléron; Modélisation; Crassostrea gigas; Charente; Trézence.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/00077/18796/16373.pdf

Aspects biométriques et biochimiques de la croissance de l'huître Crassostrea virginica en élevage suspendu à Solomons (Baie de Chesapeake)
Provedor de dados: 5
Autores: Goulletquer, Philippe; Prou, Jean; Heral, Maurice.
Growth and proximate biochemical composition of the American oyster Crassostrea virginica were studied in the Patuxent river (Maryland), located in the middle reach of the Chesapeake bay (U.S.A.). The effects of stocking densities and environmental variables (depth, temperature) were examined in 1989-1990 on oyster population by using off-bottom culture. No significant density effect was observed on the shell growth, which is described by using a seasonally oscillating function. In contrast, the meat growth and the proximate biochemical composition were bath affected by the stacking density and the depth location. The variability of the resulting effects was observed based on a seasonal trend. Different hypothesis mainly related tO environmental conditions...
Tipo: Text
Palavras-chave: USA; Chesapeake Bay; Oysters; Growth; Biochemical composition; Crassostrea virginica; Croissance; USA; Chesapeake Bay; Huîtres; Biochimie; Biométrie; Crassotrea virginica.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/1994/publication-3076.pdf

Report of the study group on pollution affecting shellfish in aquaculture and natural populations - 1991
Provedor de dados: 5
Autores: Heral, Maurice; Meixner, R.; Spencer, B.; Walsh, G.; Worms, J.
This document is a report of a Study Group of the International Council for the Exploration of the Sea and does not necessarily represent the views of the Council. Therefore it should not he quoted without consultation with the General Secretary.
Tipo: Text
Palavras-chave: Natural populations; Aquaculture; Shellfish; Pollution; Populations naturelles; Aquaculture; Coquillages; Pollution.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/1991/acte-3048.pdf

The decline of Chesapeake Bay oyster population : a century of habitat destruction and overfishing
Provedor de dados: 5
Autores: Rotschild, B. J.; Ault, J. S.; Goulletquer, Philippe; Jensen, W. P.; Heral, Maurice.
The  oyster population in the Maryland portion of the Chesapeake Bay has declined b y more than 38-fold since the early part of the century. Although the effects of fishing have been implicated, the decline has been attributed primarily to water quality and recently oyster disease. The decline has also been thought to have affected the biota and chemistry of the Bay. Our analysis provides a quantitative demonstration that the long-term declines are largely the result of habitat loss related to over fishing early in the century, stock over fishing, early in the century' through the recent times. Furthermore, the major ecological effects on Chesapeake Bay occurred well-before World War 1/, before industrialization and the prevalence of disease
Tipo: Text
Palavras-chave: USA; Chesapeake Bay; Prevalence of disease; Industrialization; Diseases; Crassostrea virginica; Oysters.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/1991/acte-3058.pdf

Variations des productions de biodépôts (feces et pesudofeces) de l'huître Crassostrea gigas dans un estuaire macrotidal : baie de Marennes-Oléron
Provedor de dados: 5
Autores: Razet, Daniel; Heral, Maurice; Prou, Jean; Legrand, Jacqueline; Sornin, Jean-marc.
The continuous obtention of current (speed and direction) turbidity and phytoplanktonic   fluorescence was achieved for 9 successive days during the month of May 1988. Each two hours, during the day, the faeces and pseudofaeces productions of 7 oysters have been sampled individualy. The filtration rate were calculated in continuous. It appeared that the concentration in particular matter and also the planktonic fluorescence fluctuated in direct relation with the water depth, the origin of the water masses and the speed of the wind. During the tidal cycle the mean filtration rate was constant which induced a food consumption largely variable. The oysters were always above the limit of pseudofaeces production which regulated the ingested quantity. Their...
Tipo: Text
Palavras-chave: Faeces; Pseudofaeces; Sort; Crassostrea gigas; Fèces; Psueofèces; Tri; Crassotrea gigas.
Ano: 1990
URL: http://archimer.ifremer.fr/doc/1990/publication-3031.pdf

Etude des potentialités conchylicoles du Pertuis Breton. Proposition d'étude. Suite aux réunions de la commission de contrôle des filières du 6 juin 1995 et du 10 avril 1996
Provedor de dados: 5
Autores: Goulletquer, Philippe; Heral, Maurice.
Le développement de la mytiliculture dans un bassin conchylicole peut aboutir à la surexploitation du site avec des conséquences néfastes pour les populations en cours d'exploitation. Pour cette raison, il est particulièrement important de développer un plan d'aménagement de bassins tels que le Pertuis Breton considérant l'ensemble des utilisateurs de cet espace. A moyen terme, le développement d'un modèle mathématique est l'outil plus approprié pour tester et valider les différents schémas d'aménagement, permettant ainsi de limiter l'impact sur l'existant. Pour un tel modèle, une parfaite connaissance des caractéristiques biologiques et physico- chimiques du milieu est nécessaire. Au délà de la biomasse en élevage, sa répartition spatiale, ses besoins...
Tipo: Text
Ano: 1996
URL: http://archimer.ifremer.fr/doc/00406/51771/52369.pdf

Conditions d'apparition de densités accrues de dinoflagellés Dinophysis dans le pertuis d'Antioche et les eaux adjacentes. Campagnes Dinopertuis 89
Provedor de dados: 5
Autores: Delmas, Daniel; Herbland, Alain; Maestrini, Serge; Mornet, Francoise; Morand, Philippe; Spano, Anna-maria; Burgeot, Thierry; Margat, Sylvie; Charpentier, Gabriel; Fillon, Alain; Leguay, Didier; Thomas, Gerard; Bacher, Cedric; Heral, Maurice; Prou, Jean.
Environmental and species features which lead to increases in cell density of the D.S.P. Dinoflagellate Dinophysis in inshore and offshore waters of the île de Ré - île d'Oléron area, France (cruises "Dinopertuis89"). Four weekly sampling series have been carried out, within 10 May – 31 May 1989, at 24 stations located from inshore to offshore waters of the "île de Ré" - "île d’Oléron" area, with the aim to investigate (i) whether Dinophysis increases in cell density occur first in offshore waters and then, eventually, are pushed to the coast, or develop simultaneously in the whole area, and (ii) whether there are some environmental conditions which are related to Dinophysis blooms. Depths of sampling have been stated on the bas is of STD profiles. All...
Tipo: Text
Ano: 1990
URL: http://archimer.ifremer.fr/doc/00174/28532/26916.pdf

Production des micro-algues des claires ostréicoles en relation avec l'azote organique dissous excrété par les huîtres
Provedor de dados: 5
Autores: Robert, Jean-michel; Maestrini, Serge; Heral, Maurice; Zanette, Yvan.
Estimations of algal growth potential (AGP) of oyster-pond waters have been made by the use of bioassays and nutrient analysis. Data obtained demonstrated that nitrogen is the nutrient Iimiting AGP and that an important part of algal biomass is supported by organic nutrients. Such an uptake ranges from 0.6 to 30.7 µg-at.I-1 nitrogen ; which represents up to six times the total amount of inorganic nitrogen taken up. U.V oxydation and subsequent chemical analysis shown DON concentrations in oyster-pond waters varied with oyster presence or absence: values recorded were 10-40 µg-at N.I-1 when oysters were not present, and up to 50-60 µg-at N.I-1 when oysters were covering the bottom of the pond. The oyster Crassostrea gigas was demonstrated to excrete 77-93 %...
Tipo: Text
Palavras-chave: Photoheterotrophy; Excretion by oysters; Dissolved organic nitrogen; Yield index; Oyster pond; Photohétérotrophie; Excrétion de l'huître; Azote organique dissous; Indice de fertilité; Claire à huîtres.
Ano: 1981
URL: http://archimer.ifremer.fr/doc/1981/acte-2946.pdf

Decline of the Chesapeake Bay oyster population : a century of habitat destruction and overfishing
Provedor de dados: 5
Autores: Rothschild, Bj; Ault, Js; Goulletquer, Philippe; Heral, Maurice.
The oyster population in the Maryland portion ot Chesapeake Bay, USA, has declined by more than 50-Iold since the early part of this century. The paper presents evidence that the mechanical destruction of habitat and stock over fishing have been important factors in the decline, even thouqh it is commonly thought that 'water quality' and, more recently, oyster diseases are critical. Quantitative analyses show that the long-term decline 01 oysters largely resuIts from habitat loss associated with intense fishing pressure early in this century and stock over fishing from early in the century throuqh recent limes. Furthermore, the major ecological effects on Chesapeake Bay occurred weIl betore World War II, before industrialization and the reported prevalence...
Tipo: Text
Palavras-chave: OYSTERS; POPULATION DYNAMICS; OVERFISHING.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/1994/publication-3080.pdf

Premières observations sur l'introduction de la faune associée au naissain d'huîtres japonaises Crassostrea gigas (Thunberg), importé sur la Côte Atlantique française
Provedor de dados: 5
Autores: Gruet, Yves; Heral, Maurice; Robert, Jean-marie.
The intentional establishment of the Japanese oyster Crassostrea gigas (Thunberg) in replacement of the Portuguese oyster caused numerous biological problems. The possible introduction of some Turbellariae, oyster predators, was at the origin of the regulation concerning the "stay in freshwater" of the spat. The implantation of other microorganisms drew our attention. Our results, though fragmentary, show that some Japanese species live on our coasts (Bay of Bourgneuf and Traiet du Croisic) a year after the immersion of the original collectors: Annelida Hydroides ezoensis, Cnidarian Aiptasia pulchella, Mollusc Anomia chinensis, Cirripedes Balanus amphitrite amphitrite and Balanus albicostatus. The survival chances seem to vary according to the oyster...
Tipo: Text
Ano: 1976
URL: http://archimer.ifremer.fr/doc/1976/publication-4927.PDF

Modélisation de l'écosystème du bassin de Marennes-Oléron (rapport 1992)
Provedor de dados: 5
Autores: Raillard, Olivier; Soletchnik, Patrick; Heral, Maurice; Prou, Jean; Bougrier, Serge; Razet, Daniel; Geairon, Philippe; Barille, Laurent; Guezennec, Loïc.
Les expérimentations on continu sur le site du Chapus au centre du bassin de Marennes-Oléron pendant le mois de mai 1991 et d'octobre 1991 ont permis de préciser la filtration des huîtres en fonction de la variabilité de la charge particulaire. Ces nouveaux résultats permettent d'affiner les modèles de croissance des huîtres. Un nouveau modèle de croissance phytoplanctonique permet de démontrer la sensibilité du bassin de Marennes-Oléron aux apports de nitrates provenant de la Charente, et leur impact sur la croissance des huîtres. L'étude des caractéristiques mécaniques des vases et des biodépôts ainsi que l'étude de l'agitation (houle et clapots, permet de modifier et de préciser les formulations d'un nouveau modèle de transport particulaire représentant...
Tipo: Text
Palavras-chave: Séries en continu; Filtration; Crassostrea gigas; Modèle phytoplanctonique; Sédiment; Modèle de transport particulaire; Bassin de Marennes Oléron.
Ano: 1992
URL: http://archimer.ifremer.fr/doc/00048/15907/13335.pdf

Why carrying capacity models are useful tools for management of bivalve molluscs culture
Provedor de dados: 5
Autores: Heral, Maurice.
In areas where oyster or mussel culture is very intensive, declines of growth rate and decreases of survival rate have occurred. For these reasons, plans have been proposed to regulate the cultivated biomasses in order to fit the carrying capacity of the different ecosystems (Heral et al 1990; Heral, 1991). In areas where new aquaculture of molluscs is beginning, oyster or mussel farmers need to know how large the extension of the culture could be and what the maximal densities should be in order to obtain the maximum economic benefit. Furthermore, as mollusc cultures are developed in coastal areas, they are very susceptible to changes in environmental conditions that can modify trophic relationships, or directly reduce growth rate, physiological...
Tipo: Text
Palavras-chave: Oyster model; Analytical model; Bivalve molluscs culture; Models.
Ano: 1993
URL: http://archimer.ifremer.fr/doc/1993/publication-6104.PDF

Perspectives de développement de l'élevage de la palourde japonaise Ruditapes philippinarum dans le bassin ostréicole de Marennes-Oléron
Provedor de dados: 5
Autores: Goulletquer, Philippe; Nedhif, Mohamed; Heral, Maurice.
The complete Manila clam's breeding cycle (Ruditapes philippinarum ) in oysters ponds (claires) permits  to obtain a length of 25 mm after 1 year with a density range of 200 animals/m2 . As the primary production is restricted, the breeding biomass during the second year is limited to 500 g.m2 corresponding to a density between 30 to 50 clams..m-2. For an increase of the production it is necessary to extend the cultivated area to the tida1 bottom of the Bay of Marennes-Oleron. It appears that the man tidal level between + 2 and + 2.5 15 necessary with a density range of 200.m-2 to reach, the market size nine months later. The harvest sould be done before winter time to avoid a large 1055 of the flesh which can cause high levels of mortality.
Tipo: Text
Palavras-chave: Marennes Oleron; Breeding; Clams; Ruditapes philippinarum; Marennes Oléron; Elevage; Palourdes; Ruditapes philippinarum.
Ano: 1986
URL: http://archimer.ifremer.fr/doc/1986/acte-2966.pdf

Qualité des eaux nécessaires en zone conchylicole
Provedor de dados: 5
Autores: Heral, Maurice.
Les problèmes liés, aux métaux lourds, aux contaminations bactériennes et virales et à la pollution physico-chimique générale étant traités ultérieurement, le présent exposé sera consacré aux paramètres biotiques et abiotiques qui conditionnent la production des mollusques. Les exemples cités seront pris pour la plupart d'entre eux dans le bassin conchylicole de Marennes-Oléron dont la production importante - 40 et 50 % du total national - justifiait un effort particulier des laboratoires de recherche. [OCR NON CONTRÔLE]
Tipo: Text
Palavras-chave: Bassin Marennes Oléron; Paramètres biotiques; Paramètres abiotiques; Qualité eaux; Zone conchylicole.
Ano: 1983
URL: http://archimer.ifremer.fr/doc/1983/acte-6795.PDF

Evolution et état du cheptel ostréicole dans le bassin de Marennes-Oléron: intérêt d'une régulation
Provedor de dados: 5
Autores: Heral, Maurice; Bacher, Cedric; Razet, Daniel; Prou, Jean; Deslous-paoli, Jean-marc.
Le bassin conchylicole de Marennes-Oléron assure 40 % des 100 000 tonnes d ' huîtres commercialisées annuellement en moyenne en France (20 000 emplois, 1 milliard de chiffre d'affaire) . La modélisation des équilibres qui s'établissent entre l es stocks mis en culture , et la production annuelle , réalisée par la station IFREMER de La Tremblade , a mis en évidence les résultats suivants : Lorsque la biomasse augmente : a) La production plafonne vers 40 000 tonnes pour une biomasse de l'ordre de 80 000 tonnes avec l'huître japonaise, ce qui correspond à une biomasse équivalente de 130 000 tonnes d'huîtres portugaises. b) La durée du cycle de production d'une huître de 70 g passe de 2 ans à 4 ans. c) Les mortalités courantes passent simultanément de 20 % à...
Tipo: Text
Palavras-chave: Production; Ostréiculture; Biomasse; Modélisation; Marennes Oléron.
Ano: 1986
URL: http://archimer.ifremer.fr/doc/00048/15909/13338.pdf

Bilan énergétique chez les mollusques bivalves : terminologie et méthodologie - Compte rendu du groupe de travail réuni au laboratoire national "Ecosystème conchylicole" de l'IFREMER La Tremblade (13 et 14 septembre 1984)
Provedor de dados: 5
Autores: Heral, Maurice; Lucas, Albert; Deslous Paoli, Jean-marc; Goulletquer, Philippe; Masse, Henri; LABEIM (Laboratoire de Biologie et d'Ecologie des Invertébrés Marins).
En septembre 1984, MM. HERAL et DESLOUS-PAOLI organisèrent à La Tremblade, une "réunion méthodologie expérimentale mollusques". Cette rencontre faisait suite à un bref état qui s'était engagé au Congrès de Montpellier sur les "Bases biologiques de l'Aquaculture", où il était apparu que la terminologie et la méthodologie concernant le métabolisme des bivalves devaient être clarifiées. Grâce à une large information auprès des spécialistes français de la physiologie des bivalves, la réunion à La Tremblade a réuni un grand nombre de participants très motivés. Pendant 2 jours des discussions très animées ont permis de bien comprendre les échanges entre les bivalves et leur environnement et d'y jeter un regard neuf, ce qui impliquait une analyse critique du...
Tipo: Text
Palavras-chave: Terminologie; Méthodologie; Bilan d'énergie; Physiologie; Bivalve; Terminology; Methodology; Energy budget; Physiology; Bivalve molluscs.
Ano: 1987
URL: http://archimer.ifremer.fr/doc/00014/12562/9432.pdf

Decline of oyster production in the Maryland portion of the Chesapeake Bay: Causes and perspectives
Provedor de dados: 5
Autores: Heral, Maurice; Rothschild, Brian J .; Goulletquer, Philippe.
The historical landings of the oyster production are described for the Maryland part of the Chesapeake Bay. The different trends are analysed concurently with the main events and management strategies which occured on the bay. Three main periods are identified : - the greatest fishery from 1840 to 1890 with a large overfishing and the destruction of the oyster habitat caused by the oyster gears, - the decrease and stable landings from 1900 to 1980 due to the failure of the reseeding plan connected to the heavy sedimentation and the anoxic summer conditions, - the large decrease of the production (1981-1988) caused by high mortalities related to diseases (MSX and Perkinsus marinus) prédation and management practices. Alternative strategies for restoration...
Tipo: Text
Ano: 1990
URL: http://archimer.ifremer.fr/doc/1990/acte-2393.pdf

Système d'informatique géographique et conchyliculture : indices de productivité
Provedor de dados: 5
Autores: Prou, Jean; Heral, Maurice.
Geographical information systems collect and integrate geographically referenced data of diverse nature (database, model results, etc.). Comparing information from different sources can help formulate productivity indexes.
Tipo: Text
Palavras-chave: Conchyliculture; Système d'Information Géographique; SIG.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/1997/acte-3257.pdf

Protocoles d'extraction chimique de la matière organique particulaire : application au domaine estuarien
Provedor de dados: 5
Autores: Etcheber, H.; Heral, Maurice; Relaxans, J. C.
There are several bio geochemical methods of studying particulate organic matter (0,45-300 µm). The main techniques employed are described ; special attention has been paid to extractive processes (chemical attack of samples and study of extracted fraction).  Although these techniques are simple, various difficulties can arise : results obtained by various authors cannot be compared when techniques used differ. Furthermore the environmental interpretation of extracted functions is not always very clear.  Extractive methods, which most often use harsh chemical extractants, do not provide accurate measurements of the importance of labile organic fraction. We propose therefore a series of chemical attacks of increasing strength and a correlation of results...
Tipo: Text
Palavras-chave: EstUARIES; Labile organic matter; Chemical extractive methods; Particulate organic matter; Extuaires; Matière organique labile; Méthode d'extraction chimique; Matière organique particulaire.
Ano: 1985
URL: http://archimer.ifremer.fr/doc/1985/publication-2957.pdf

Bilan energetique d'une population naturelle de Crepidula fornicata dans le bassin de Marennes-Oleron
Provedor de dados: 5
Autores: Deslous-paoli, Jean-marc; Heral, Maurice; Masse, H.
An energy budget has been evaluated for a natural population of Crepidula fornicata living at low water of spring tides in the oyster farming basin of Marennes-Oleron. This budget of production was estimated according to the position along the chain. The average biomass for an individual representative of the population was equivalent to 1.87 Kjoules, and the annual consumption C was 20.08 Kjoules/year. The energy budget expressed in percent of energy consummates was: C = Pg + Pr + Ps + R + F; 100 = 4.6 + 1.6 + 0.8 + 48 + 45. This budget is compared with literature data on other herbivorous gastropods and with those calculated for Crassostrea gigas in the same locality.
Tipo: Text
Palavras-chave: Bivalvia; Crepidula fornicata; Seasonal variations; Population structure; Energy budget; Bassin de Marennes Oléron; Bilan énergétique; Crepidula fornicata.
Ano: 1983
URL: http://archimer.ifremer.fr/doc/1983/acte-1181.pdf

Contrat aménagement de la zone de marais. Conséquences de l'aménagement agricole sur les autres activités. Compte-rendu final de la recherche
Provedor de dados: 5
Autores: Chevallier, Claude; Heral, Maurice; Razet, Daniel.
Dans le contexte de développement agricole très actif des trente dernières années les marais atlantiques littoraux qui couvrent, pour leur partie endiguée environ 300.000 ha ont été et continuent d'être soumis à des transformations importantes qui influent sur la circulation et la qualité des eaux de surface. Ce développement, visant à une amélioration de la productivité et à une meilleure intégration de l'activité agricole dans les grands processus économiques, s'est appuyé, là comme ailleurs, sur les intensifications fourragère et surtout céréalière. L'adaptation de ce modèle général aux caractéristiques écologiques du milieu nécessitait de limiter les effets des excès d'eau hivernaux sur la mise en culture ainsi que ceux de la sécheresse estivale sur...
Tipo: Text
Palavras-chave: Conchyliculture; Agriculture; Marais; Aménagement; Assainissement; Qualité eau; Caractéristiques hydrauliques; Moeze; Charente-Maritime.
Ano: 1989
URL: http://archimer.ifremer.fr/doc/00118/22953/20780.pdf

Rapport d'activité année 1979 du Laboratoire de Biologie Conchylicole de La Tremblade
Provedor de dados: 5
Autores: Heral, Maurice.
Rapport d'activité du Laboratoire de Biologie Conchylicole de La Tremblade concernant l'année 1979
Tipo: Text
Palavras-chave: Conchyliculture; Physiologie; Crassostrea gigas; Mytilus edulis; Reproduction; Estimation stock; Croissance; Ruditapes decussatus; Ruditapes philippinarum; Marennes Oléron.
Ano: 1979
URL: http://archimer.ifremer.fr/doc/00070/18088/15636.pdf

Elevage de palourdes sous filet en mileu fermé
Provedor de dados: 5
Autores: Peyre, Roger; Zanette, Yvan; Heral, Maurice.
Japanese clam (Ruditapes philippinarum) and European clam (Ruditapes decussates) farming based on spat produced in hatcheries has gone beyond the experimental stage on the Atlantic coasts since the research of Latrouite et Claude (1976), Lucas (1977), Flassch (1979), Dréno (1979) and Gras (soon to be published). It has thus become necessary to develop farming procedures reliable enough to be handed over to the professionals in the business.
Tipo: Text
Palavras-chave: Marennes Oléron; Ruditapes decussatus; Ruditapes philippinarum; Elevage; Palourdes.
Ano: 1980
URL: http://archimer.ifremer.fr/doc/1980/publication-3006.pdf

Rapport annuel d'activité 1982 du Laboratoire Cultures Marine et Aménagement du Littoral La Tremblade
Provedor de dados: 5
Autores: Heral, Maurice.
Rapport annuel d'activité concernant l'année 1982 du Laboratoire Cultures Marines et Aménagement du Littoral de La Tremblade - Institut Scientifique et Technique des Pêches Maritimes
Tipo: Text
Palavras-chave: Rapport activité; Conchyliculture; Production; Estimation stock; Valorisation claires ostréicoles; Sélection Génétique; Bassin de Marennes Oléron.
Ano: 1982
URL: http://archimer.ifremer.fr/doc/00087/19780/17417.pdf

Contrat aménagement de la zone de marais : conséquence de l'aménagement agricole sur les autres activités - Compte rendu final de la recherche Mars 1989
Provedor de dados: 5
Autores: Chevalier, Claude; Heral, Maurice; Razet, Daniel.
Dans le contexte de développement agricole très actif des trente dernières années les marais atlantiques littoraux qui couvrent, pour leur partie endiguée environ 300.000 ha. ont été et continuent d'être soumis à des transformations importantes qui influent sur la circulation et la qualité des eaux de surface. Ce développement, visant à une amélioration de la productivité et à une meilleure intégration de l' activité agricole dans les grands processus économiques, s'est appuyé, là comme ailleurs, sur les intensifications fourragère et surtout céréalière. L'adaptation de ce modèle général aux caractéristiques écologiques du milieu nécessitait de limiter les effets des excès d'eau hivernaux sur la mise en culture ainsi que ceux de la sécheresse estivale sur...
Tipo: Text
Palavras-chave: Marais atlantique; Littoral; Agriculture; Conchyliculture; Impact; Compatibilité; Charente Maritime Dep.
Ano: 1989
URL: http://archimer.ifremer.fr/doc/00071/18235/15795.pdf

Separate effects of triploidy, parentage and genomic diversity upon feeding behaviour, metabolic efficiency and net energy balance in the Pacific oyster Crassostrea gigas
Provedor de dados: 5
Autores: Hawkins, Ajs; Magoulas, A; Heral, Maurice; Bougrier, Serge; Naciri-graven, Y; Day, Aj; Kotoulas, G.
Triploid oysters were induced using cytochalasin B upon retention of either the first (meiosis I triploids) or the second (meiosis II triploids) polar body in embryos from a single cohort derived from mixed parentage. Allozyme and microsatellite assays enabled the confirmation of both parentage and triploidy status in each oyster. Comparison of meiosis I triploids, meiosis II triploids and diploid siblings established that improved physiological performance in triploids was associated with increased allelic variation, rather than with the quantitative dosage effects of ploidy status. An unidentified maternal in¯uence also interacted with genotype. Among full sibs, allelic variation measured as multi-locus enzyme heterozygosity accounted for up to 42% of...
Tipo: Text
Ano: 2000
URL: http://archimer.ifremer.fr/doc/2000/publication-2716.pdf

Les voies de calcul de la filtration
Provedor de dados: 5
Autores: Soletchnik, Patrick; Heral, Maurice; Razet, Daniel; Geairon, Philippe.
Dans le cadre des études de physiologie, la fonction de filtration intervient dans le calcul du bilan énergétique, ou permet de déterminer la quantité d'aliment consommé par les mollusques filtreurs. Cette fonction peut également être considérée dans les relations avec le poids de l'animal, la température et un certain nombre d'indices de qualité et de quantité de l'aliment dont se nourrit le bivalve. Dans un contexte de coopération internationale entre scientifiques anglais, espagnols et français, une expérimentation physiologique sur les mollusques a été réalisée en septembre 1991 à l'IFREMER La Tremblade. De nombreux objectifs motivent cette expérimentation : la comparaison inter espèces, la confrontation des techniques mises en oeuvre par les...
Tipo: Text
Palavras-chave: Physiologie; Filtration; Huître creuse; Crassostrea gigas; Alimentation.
Ano: 1992
URL: http://archimer.ifremer.fr/doc/00102/21303/18916.pdf

Approche de la capacité trophique d'un écosystème conchylicole
Provedor de dados: 5
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

Rapport de mission Croatie. 13 juillet-27 juillet 1994
Provedor de dados: 5
Autores: Heral, Maurice; Prou, Jean.
Objectif de la mission : Déterminer la faisabilité d'un programme bilatéral France-Croatie pour évaluer la capacité trophique de la baie de Mali-Ston pour l'élevage d'huîtres plates et de moules. Élaboration d'un  programme et acquisition sur le site des principaux paramètres physico-chimiques et trophiques de la baie de Mali-Ston.
Tipo: Text
Ano: 1994
URL: http://archimer.ifremer.fr/doc/00389/50071/50664.pdf

Rapport d'activité 1989 du Laboratoire National Ecosystèmes Conchylicoles (LEC) - La Tremblade
Provedor de dados: 5
Autores: Heral, Maurice.
Tipo: Text
Palavras-chave: Rapport activité; Conchyliculture; Estimation biomasse; Hydrobiologie; Physiologie; Crassostrea gigas; Modélisation; Bassin de Marennes Oléron.
Ano: 1989
URL: http://archimer.ifremer.fr/doc/00077/18838/16413.pdf

Particle selection in the oyster Crassostrea gigas (Thunberg) studied by pigment HPLC analysis under natural food conditions
Provedor de dados: 5
Autores: Pastoureaud, Annie; Heral, Maurice; Prou, Jean; Razet, Daniel; Russu, Patricia.
Selective feeding in the adult oyster Crassostrea gigas was studied using natural particle assemblages in the estuarine environment of the Bassin de Marennes Oleron (France). Oysters were exposed to natural variations of suspended particulate matter by direct pumping of sea water from the bay during various tidal cycles. Experiments were conducted during the spring over both spring tides and neap tides, so as to obtain a maximum range of variation in seston characteristics, spring tide being characterized by very strong currents with high loads of resuspended materials (sediment, microphytobenthos and detritus). Particles were analysed for their chloropigment content by HPLC. The native pigments consisted exclusively of chlorophyll a and c, from both...
Tipo: Text
Ano: 1996
URL: http://archimer.ifremer.fr/doc/1995/publication-3085.pdf

Utilisation du filet à plancton du type Bongo en milieu côtier
Provedor de dados: 5
Autores: Heral, Maurice.
Le filet Bongo est un filet à plancton américain dont l'utilisation se généralise pour les études de l'lchtyoplancton. Ses dimensions, son pouvoir de filtration et son rendement en  fait un engin performant pour la recherche des larves de poissons. Il est recommandé par l'I.G.N.A.F. groupe pré-recrutement du hareng et il le sera prochainement dans F.A.O. standard Techniques for Pelagic Fish Egg and Larva Sarveys. L' ISTPM utilise ce filet, depuis 1971 , dans de nombreuses campagnes à bord de la Thallassa, du Cryos, de la Pelagia , du Roselys et de Ichtys. En 1975, nous avons décidé d'utiliser ce filet dans des études côtières que l'ISTPM mène en Manohe et en Mer du Nord. Ces travaux ont pour but d'établir un inventaire halieutique qualitatif et quantitatif...
Tipo: Text
Ano: 1975
URL: http://archimer.ifremer.fr/doc/00387/49875/50433.pdf

Utilisation des dosages d'adenosine tri-phosphate (A T P) dans l'estimation des pertes de matières vivantes au cours du transit dans les condenseurs de la centrale de Dunkerque
Provedor de dados: 5
Autores: Heral, Maurice.
Some adenosine triphosphate measurements enabled us to quantify the planktonic mortality caused by the transfer of cooling waters in the condensers of the thermic plant of Dunkerque. Concerning phytoplankton, the chlorine used as a biocide causes a loss of 70 to 95 % of the absorbed biomass. An ATP extraction method has been developed for zooplankton in order to monitor the evolution of live planktont. Results show that losses are low, if not null and that some species seem to proliferate right next to the discharge. Another approach of fish larva mortality rate, through counting on the aspiration grids seems to prove it very high.
Tipo: Text
Palavras-chave: Rejet; Centrale thermique; Mortalité planctonique; Dosages adénosine triphosphate.
Ano: 1976
URL: https://archimer.ifremer.fr/doc/1976/acte-6215.PDF

Amélioration de la qualité chez l'huître creuse Crassostrea gigas par sélection de souches performantes - Contrat de Plan Etat Région Poitou-Charentes 1994-1998 - Rapport année 1995
Provedor de dados: 5
Autores: Boudry, Pierre; Naciri, Yamama; Heral, Maurice; Collet, Bertrand; Bougrier, Serge; Geffard, Olivier; Ledu, Christophe; Phelipot, Pascal; Heurtebise, Serge; Gerard, Andre.
Le programme de recherche présenté ci-dessous est le fruit d'une réflexion conjointe entre généticiens et physiologistes afin de mettre sur pied un ensemble d'expériences permettant d'étudier les bases génétiques de la variabilité des caractères impliqués dans la croissance chez l'huître creuse, Crassostrea gigas.
Tipo: Text
Palavras-chave: Génétique; Sélection génétique; Génétique des populations; Croissance; Crassostrea gigas.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/00044/15518/12905.pdf

Le tri préingestif particulaire chez l'huître Crassostrea gigas et la moule Mytilus edulis
Provedor de dados: 5
Autores: Bougrier, Serge; Heral, Maurice; Hawkins, Andrew; Bayne, Barry.
Using flow cytometry techniques, it is possible to study both the potential impact of filter-feeder bivalves on microalgal communities as well as the changes in the grazed microalgae and the behaviour of these bivalves whose diet is composed of a mixture of different species.
Tipo: Text
Palavras-chave: Physiologie; Mytilus edulis; Crassostrea gigas; Tri préingestif.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/1997/acte-3252.pdf

Report of the study group on pollution affecting shellfish in aquaculture and natural populations - 1992
Provedor de dados: 5
Autores: Heral, Maurice.
In La Rochelle (october 1991) the following recommendations of consultative committee approved by the delegates meeting for this study group were :  Attention was drawn to the fact that the study group on Pollution Meeting Shellfish in Aquaculture and Natural Populations (C.Res. 1991/2 : 45) was one of the council's first attempts to investigate the effect of pollution on fisheries. Delegates were encouraged to ensure a better representation of proper experts at the 1992 meeting since the 1991 meeting had been poorly attended. The recommendations from the Shellfish Committee were adopted by the council as C.Res. 1992/2 : 45 jointly with MEQC, Mariculture and ACMP.
Tipo: Text
Palavras-chave: Pollution; Shellfish Committee; Recommendation.
Ano: 1992
URL: http://archimer.ifremer.fr/doc/1992/acte-3063.pdf

Eléments azotés de la colonne d'eau et de l'interface eau-sédiment du bassin de Marennes-Oléron : influence des cultures d'huîtres
Provedor de dados: 5
Autores: Feuillet-girard, Michelle; Heral, Maurice; Sornin, Jean-marc; Deslous-paoli, Jean-marc; Robert, Jean-michel; Mornet, Francoise; Razet, Daniel.
The respective influences of the sediment and of oyster (Crassostrea gigas) farming on the accumulation and the recycling of different forms of organic and inorganic nitrogen are described. Fluxes of dissolved inorganic and organic forms of nitrogen were studied between the water column, the water overlying the sediment and the pore waters, while for particulate forms the fluxes were studied between suspended material, the "biodeposits" (faeces and pseudofaeces of Crassostrea) and the sediment. The flux of inorganic nitrogen amounts to 10.5 106 g.m(-2). Yr(-1), while that of organic nitrogen is half this figure. The particulate flux is 15.106 g.m(-2).yr(-1). On the other hand, the phytoplanktonic nitrogen accounts for only 6% of the total particulate...
Tipo: Text
Palavras-chave: Marenne Oleron; Sediment; Pore water; Interface; Crassostrea gigas; Nitrogen; Marennes Oléron; Sédiment; Eau interstitielle; Adsorption; Interface; Crassostrea gigas; Azote.
Ano: 1988
URL: http://archimer.ifremer.fr/doc/1988/publication-2878.pdf

Modélisation des écosystèmes conchylicoles : bassin de Marennes-Oléron - Rapport de fin de Contrat
Provedor de dados: 5
Autores: Heral, Maurice; Bacher, Cedric; Razet, Daniel; Prou, Jean; Deslous-paoli, Jean-marc; De Pontual, Helene; Raillard, Olivier; Ravail, Brigitte; Maestrini, Serge; Mornet, Francoise; Menesguen, Alain; Sautour, Benoit; Robert, Jean-michel.
Les termes du contrat passé entre le Fond de la Recherche et de la Technologie et l'IFREMER précisent qu ele programmer a pour objectif une gestion rationnelle du milieu conchylicole avec notamment une mise au point de modèles (voir notification de l'aide en annexe). Un premier modèle appelé modèle global par analogie avec les modèles de pêche met en évidence la limite de la capacité trophique du bassin de Marennes-Oléron pour les huîtres cultivées. Un modèle analytique avec un modèle physique simple permet dans un premier temps de développer un modèle de croissance des huîtres en fonction de la nourriture disponible et d'effectuer des simulations qui confirment l'influence du stock sur les performances de croissance des bivalves. Un troisième approche...
Tipo: Text
Palavras-chave: Modélisation; Production; Biomasse; Huîtres creuses; Crassostrea gigas; Capacité biotique; Bassin de Marennes Oléron.
Ano: 1989
URL: http://archimer.ifremer.fr/doc/00048/15904/13332.pdf

Evolution of oyster aquaculture : problems and perspectives
Provedor de dados: 5
Autores: Heral, Maurice.
The total marine molluscs produced by aquaculture had increased from 1984 to 1990 by 1 000 000 tons going from 1 993 985 tons to 2 964 688 tons. The oyster production remained constant with 870 000 tons. Crassostrea gigas, the Japanese oyster, represented more than 80 % of the oyster production but high mortalities appeared in different countries connected to end of winter and summer mortalities and development of new diseases. The cultivation of Crassostrea virginica, the American oyster, was limited (80 000 tons) by the spreading of two diseases (MSX and dermo) destruction of habitat and over-exploitation. Production of the fiat oyster Ostrea eduIis was still very limited by the presence of the Bonamia diseases in a11 the countries except on...
Tipo: Text
Palavras-chave: Ostrea edulis; Crassostrea virginica; Crassostrea gigas; Huîtres; Culture; Production; Ostréiculture.
Ano: 1993
URL: http://archimer.ifremer.fr/doc/1993/acte-3067.pdf

Influence of oyster farming Crassostrea gigas on the phosphate cycle in an intertidal zone : the role of biodeposition
Provedor de dados: 5
Autores: Sornin, Jean-marc; Feuillet, Michelle; Heral, Maurice; Fardeau, Jean-claude.
Some aspects of the phosphorus cycle were studied in the estuarine bay of Marennes, Oléron, an area of intensive cultivation of Crassostrea gigas on the west coast of France. The annual cycle of dissolved phosphorus (mineral and organic) in the water column, interstitial water and at the sediment-water interface was followed, as well as the particulate phosphorus (total and assimilable) in sediments and in suspension. A comparison of the seasonal variations in these different forms of phosphorus in the suspended matters shows a deficit in "biodeposits" (sedimented faeces and pseudofaeces from Crassostrea gigas) equivalent to 20 mg.m -2.d -1 for assimilable phosphorus in July and September-October. This may be the result of consumption by the oysters, since...
Tipo: Text
Palavras-chave: Phosphore; Crassoslrea gigas; Biodéposition; Dilution isotopique; Marennes-Oléron; Phosphorus; Crassostrea gigas; Biodeposition Isotopic; Dilution; Marennes-Oléron.
Ano: 1986
URL: http://archimer.ifremer.fr/doc/1986/publication-2973.pdf

Les peintures marines antisalissures et leur impact sur l'ostréiculture
Provedor de dados: 5
Autores: Alzieu, Claude; Heral, Maurice; Dreno, Jean-paul.
On 17 January 1982, the Minister of the Environment issued a decree limiting the use of anti-fouling paints that have organostannic derivatives for boats of less than 25 metres in length. This decision, taken after advice from the Commission for Assessing the Ecotoxicity of Chemical Substances, was meant to protect oyster-farming against the serious pollution linked to the growing use of this type of paint. These provisions, adopted only a few months after the harmful effects of organo-tins were brought to light, made it possible to protect oyster farming in some endangered areas. Moreover, they brought on an international awareness of the ecological risks linked to the struggle against marine biological fouling.
Tipo: Text
Palavras-chave: Ostréiculture; Impact; Peintures antisalissures.
Ano: 1989
URL: http://archimer.ifremer.fr/doc/1989/publication-3025.pdf

Evolution saisonnière de la filtration de bivalves intertidaux dans des conditions naturelles
Provedor de dados: 5
Autores: Deslous-paoli, Jean-marc; Heral, Maurice; Goulletquer, Philippe; Boromthanarat, Wilaiwan; Razet, Daniel; Garnier, Jacqueline; Prou, Jean; Barille, Laurent.
The study of cultivated ecosystems, once the trophic capacity ha! been determined and the molluscan stocks estimated, requires a knowledge of  the evolution of the seasonal consumption of food by molluscs in natural conditions. For Crassostrea gigas, Mytilus edulis, Cerastoderma edule, Ruditapes philippinarum, the amount and quality of food have no effect on the filtration rate, except for the high load of mineraI seston. First an increase of the filtration rate was shown for Mytilus edulis and Cerastoderma edule at the end of winter and beginning of spring. Moreover Crassostrea gigas and Ruditapes philippinarum have shown no increase or only a small summer one. This evolution did not seem to be linked with the environmental conditions (temperature,...
Tipo: Text
Palavras-chave: Natural food; Bivalves; Filtration rates; Nourritures naturelles; Bivalves; Taux de filtration.
Ano: 1987
URL: http://archimer.ifremer.fr/doc/1987/publication-3304.pdf

Bilan énergétique de l'huître japonaise Crassostrea gigas en conditions expérimentales de laboratoire au cours du mois de septembre 1991
Provedor de dados: 5
Autores: Soletchnik, Patrick; Bougrier, Serge; Razet, Daniel; Geairon, Philippe; Prou, Jean; Heral, Maurice; Barille, Laurent.
L'étude ci dessous, réalisée chez Crassostrea gigas, a comme objectif de comparer l'effet de différents types d'aliments sur le bilan énergétique de cette espèce.
Tipo: Text
Palavras-chave: Huître creuse; Crassostrea gigas; Bilan énergétique; Sources alimentaires; Biodépots; Tri pré-ingestif.
Ano: 1992
URL: http://archimer.ifremer.fr/doc/00100/21095/18720.pdf

Bilan énergétique de l'huître creuse (Crassostrea gigas) durant la période de forte croissance en mai en Baie de Marennes-Oléron (France)
Provedor de dados: 5
Autores: Soletchnik, Patrick; Heral, Maurice; Razet, Daniel; Bougrier, Serge; Geairon, Philippe.
Ecophysiological study was conducted on the japanese oyster (Crassostrea gigas) reared in Marennes-Oléron bay (France), during May 1992. Most of the somatic growth of the oyster occured during that month. The measurements were achieved from a removable laboratory stated in Le Chapus for 3 days at different tide level (coefficient of 49, 57, and 88). The food conditions were monitored through a computer with a continuous record of the turbidity during aIl the tidal cycle.  In spite of an important variation between the food conditions in mean seston load, from 13,5 to 54,6 mg/!, the available organic matter ranged from 3 to 4,9 mg/l. The rate of organic matter in the water ranged 22 % to 9 %. The organic selection efficiency was significantly higher for the...
Tipo: Text
Palavras-chave: Energetic budget; Selection efficiency; Filtration; Crassostrea gigas; Budget énergétique; Sélection; Consommation; Crassostrea gigas.
Ano: 1993
URL: http://archimer.ifremer.fr/doc/1993/acte-3068.pdf

Introduction into France of the Japanese oyster (Crassostrea gigas)
Provedor de dados: 5
Autores: Grizel, Henri; Heral, Maurice.
The Japanese oyster (Crassostrea gigas) has been introduced in France on a large scale to replace cultivation of the Portuguese oyster (Crassostrea angulata), affected by a viral disease. The importation took place from 1971 to 1975, with broodstock coming from British Columbia (Canada) and spat from Japan. Good growth rate and success of the natural setting on the French Atlantic coast attested to the success of this implantation, with a production which reached 80000 t by 1976. The precautionary measures associated with this transfer Iimited the implantation of an introduced fauna, 15 years after, to: Balanus amphitrite, Aiptasia pulchella and, on the Mediterranean coast, Undaria pinnatifida and Laminaria japonica. The authors also discuss the possible...
Tipo: Text
Palavras-chave: Crassostrea gigas; Oyster; Introduction; Crassostrea gigas; Huître; Introduction.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/1991/publication-2760.PDF

Rapport de mission Croatie. 26 novembre-29 novembre 1996
Provedor de dados: 5
Autores: Heral, Maurice; Prou, Jean.
Tipo: Text
Ano: 1996
URL: http://archimer.ifremer.fr/doc/00389/50085/50677.pdf

Causes of decline of oyster production (Crassostrea virginica) in the Maryland portion of the Chesapeake Bay : a literature study
Provedor de dados: 5
Autores: Goulletquer, Philippe; Heral, Maurice; Rotschild, Brian.
The historical landings of Eastern oyster Crassostrea virginica are described for the Maryland part of the Chesapeake Bay. The different trends are analyzed concurrently with the main events and management strategies which occurred. Three main periods are identified : (1) the great fishery when annual oyster landings from 1840 to 1890 reached 600,000 metric tons. This period was characterized by gross overfishing and the destruction of oyster habitat by the oyster gears; (2) the reduced but stable landings from 1900 to 1980, with failure of the reseeding plan connected to heavy sedimentation and anoxie summer conditions. Landings did not exceed 80,000 metric tons; (3) the large decrease of production (1981-1988), with landings as low as 15,000 metric tons...
Tipo: Text
Palavras-chave: Production; Chesapeake Bay; Mortalities; Crassostrea virginica; Oysters; Production; Chesapeake Bay; Mortalités; Crassostrea virginica; Huîtres.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/1994/publication-3081.pdf

An example of GIS potentiality for coastal zone management: preselection of submerged oyster culture areas near Marennes-Oleron (France)
Provedor de dados: 5
Autores: Durand, H.; Guillaumont, Brigitte; Loarer, Ronan; Loubersac, Lionel; Heral, Maurice; Prou, Jean.
The Charente Maritime coast, in central western France, is the most important area for oyster and mussel production in Europe. High density, in this restricted intertidal area, induces low growing rate and socio-economic difficulties. One of the possible solutions is to shift some oysters from intertidal area to submerged areas. Bathymetry, sedimentology, hydrodynamism, fisheries and administrative rules are some conditions which are considered to establish the better selection of potential zone. The successive steps of setting up the prototype of GIS are presented: digitized traditional data from charts, extracted data from grid models (hydrodynmaic model), merging of thematic covers, proposal of favorable areas. The results are discussed especially on...
Tipo: Text
Palavras-chave: GIS; Modelisation; Bathymetry; Sedimentology; Hydrodynamism; Marennes Oleron.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/00017/12784/9725.pdf

La Conchyliculture. La gestion des bassins conchylicoles
Provedor de dados: 5
Autores: Heral, Maurice; Goulletquer, Philippe.
Tipo: Text
Palavras-chave: Conchyliculture; Gestion bassin ostréicole; Ecosystème conchylicole.
Ano: 2007
URL: http://archimer.ifremer.fr/doc/00119/23072/20912.pdf

Perspectives d'évolution et stratégies du bassin ostréicole de Marennes-Oléron
Provedor de dados: 5
Autores: Mourrieras, Olivier; Nerriere, Frédéric; Heral, Maurice.
Nous avons voulu que ce travail réponde à un double objectif. Tout d'abord, nous souhaitions nous intéresser à une activité primordiale en Charente-Maritime et développer notre savoir sur l'ostréiculture dans le bassin de Marennes-Oléron dont l'histoire est riche en événements, Ce travail nous permettait également de faire découvrir au lecteur non initié une forme de culture peu ou mal connue et qui est pourtant une importante source d'emplois et de revenus pour cette région, Nous désirions ensuite mettre à profit notre acquis théorique afin d'apporter des éléments de réponse aux divers problèmes organisationnels de production ou de commercialisation que peut rencontrer la communauté ostréicole de Marennes-Oléron aujourd'hui, si possibilité de réponse il y...
Tipo: Text
Palavras-chave: Ostréiculture; Enquête; Production; Commercialisation; Bassin de Marennes Oléron.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/00050/16158/13641.pdf

Absence de captage de Crassostrea gigas dans le bassin de Marennes-Oléron en 1981 : causes et conséquences
Provedor de dados: 5
Autores: Berthome, Jean-paul; Deslous-paoli, Jean-marc; Heral, Maurice; Razet, Daniel; Garnier, Jacqueline.
The want of C. gigas spat-catching in the Marennes-oleron basin in 1981 can be due to various different reasons which are analysed here. Physico -chemical and trophic factors that can induce variations in the quality of gametogenesis, are successively in comparison with the year 1979 when reproduction was good. The biochemical evolution and a study of gonads slow a lack in maturation in 1981 even during the summer period. Late maturation of gonads bring about physiological consequences which induced mortality of cultivated oysters at the end of winter. A feeble recruit and a decrease of the cultivated stock have economic consequences which here sketched up.
Tipo: Text
Palavras-chave: Larvae; Recrutment; Spat; Crassostrea gigas; Oysters; Larves; Recrutement; Captage; Crassostrea gigas; Huîtres.
Ano: 1982
URL: http://archimer.ifremer.fr/doc/1982/acte-2948.PDF

Rapport annuel d'activité 1980 du Laboratoire Cultures Marines et Aménagement du Littoral de La Tremblade
Provedor de dados: 5
Autores: Heral, Maurice.
Rapport annuel d'activité du Laboratoire Cultures Marines et Aménagement du Littoral de La Tremblade concernant l'année 1980
Tipo: Text
Palavras-chave: Conchyliculture; Production; Physiologie; Valorisation claires ostréicoles; Sélection génétique; Crassostrea gigas; Reproduction.
Ano: 1980
URL: http://archimer.ifremer.fr/doc/00070/18108/15655.pdf

Interface between French Shellfish Industry and Research
Provedor de dados: 5
Autores: Prou, Jean; Goulletquer, Philippe; Heral, Maurice.
Historically, research involvement in shellfish industry appeared as soon as the 19th century with studies on oyster sanitary quality and nutritive values. Those aspects were developed to satisfy consumer's demand and public health issues. Later on, rearing technologies were developed to ensure optimization of the characteristics of shellfish population dynamic such as recruitment, growth, and mortality. In a third step, management of leasing grounds allocation required studies on ecosystems' functioning. It integrated over space and time relationships between environment (as a trophic resource) and shellfish production. Presently, new challenges regarding environmental protection and consumer's satisfaction have involved studies on optimized uses of...
Tipo: Text
Palavras-chave: Zoosanitary issues; Seawater quality; Space allocation; Shellfish research; Shellfish industry.
Ano: 2004
URL: http://archimer.ifremer.fr/doc/2004/acte-6252.pdf

Ecophysiologie in situ de l'huître Crassostrea gigas dans un milieu macrotidal (bassin de Marennes-Oléron - Chapus 1991)
Provedor de dados: 5
Autores: Guezennec, Loic; Prou, Jean; Heral, Maurice; Razet, Daniel; Bougrier, Serge; Soletchnik, Patrick.
L'expérience menée lors du stage fait suite à deux expériences similaires menées en 1988 et 1990. Elle vise à étudier le comportement d'une population d'huîtres (100 individus) soumise aux variations du milieu naturel. La durée de l'expérience (3 semaines) permet de tester les effets simultanés des cycles haute mer. basse mer et celui des vives·eaux. mortes-eaux. De plus. les données acquises en continu sur le milieu (fluorescence et turbidité. salinité. température) permettront le calage des modèles courantologiques et sédimentologiques. Le choix du mois de mai pour l'expérience est déterminé par l'apparition. en général. d'un bloom phytoplanctonique à cette période de l'année. Les expériences précédentes (1988 et 1990) ont permis déjà d'appréhender la...
Tipo: Text
Palavras-chave: Ecophysiologie; Huître creuse; Crassostrea gigas; Bassin de Marennes-Oléron; Chapus; Charente Maritime.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/00102/21308/18921.pdf

Crepidula fornicata L. (mollusque, gastéropode) en baie de Marennes-Oléron : cartographie des fonds par sonar à balayage latéral et estimation du stock
Provedor de dados: 5
Autores: Sauriau, Pierre-guy; Pichocki-seyfried, C; Walker, P; De Montaudouin, Xavier; Palud, Cecile; Heral, Maurice.
Extensive and detailed subtidal ground mapping of the Marennes-Oleron Bay and Fouras-Aix areas was performed with a side-scan sonar. Side-scan sonographs gave a comprehensive view of sedimentological bottom environments and also allowed us to outline locations of grounds colonised by the gastropod mollusc Crepidula fornicata L. with a precise estimate of their surface. A sedimentological map of the centre of the Marennes-Oleron Bay is given, describing spatial organisation of the following four types of sediment: pure mud, fine sand, coarse sand and rocks. Crepidula beds were also recognised on sonographs and were estimated to cover 181 hectares in the Fouras-Aix area and 615 hectares within the Marennes-Oleron Bay. Standard sampling methods were then...
Tipo: Text
Palavras-chave: Crepidula fornicata; Cartographic; Stock; Sonar à balayage latéral; Marennes-OlCron; Crepidula fornicata; Mapping; Stock assessment; Side-scan sonar; Marennes-Oleron Bay.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/1998/publication-854.pdf

Du bassin versant au territoire maritime : la ressource hydrique objet d'une recherche intégrée et finalisée. L'exemple du bassin versant de la Charente et de la "Mer des Pertuis"
Provedor de dados: 5
Autores: Delmas, François; Heral, Maurice; Laplana, Ramon; Loubersac, Lionel; Prou, Jean.
Parmi les régions Ouest Européennes, la région Poitou Charentes se caractérise dans sa dimension économique par la présence d'activités où les cultures marines, l'agriculture et le tourisme occupent une place prédominante. Cette identité, partagée par d' autres régions, notamment atlantiques, s'appuie sur l'exploitation de la ressource hydrique et implique de plus en plus des critères de haute qualité tant vis à vis des produits finis agricoles, conchylicoles, touristiques que vis à vis de l'environnement, des paysages et des eaux. Sur cet ensemble de points la Région est dotée d'atouts indiscutables. Cependant les contraintes liées à la disponibilité de la ressource hydrique continentale comme marine et à son maintien à un bon niveau de qualité, font...
Tipo: Text
Palavras-chave: Conchyliculture; Agriculture; Charente; Marennes Oléron; Transfert eau; Modèle trophique; Gestion eau.
Ano: 1996
URL: http://archimer.ifremer.fr/doc/00018/12933/9898.pdf

Marine Molluscan Production Trends in France: From Fisheries to Aquaculture
Provedor de dados: 5
Autores: Goulletquer, Philippe; Heral, Maurice.
(NOT controlled OCR ) The main activity in French shellflshing is culturing. Most culture involves oysters, Grassostrea gigas, and Ostrea edulis; mussels, Mytilus edulis and M. galloprovincialis; and to a lesser extent the scallop, Pecten maximus, and the exotic Manila clam, Tapes philippinarum. Wild species harvested include the whelk, Buccinum undatum; abalone, Haliotis tuberculata; and bivalves, such as the cockle, Cerasioderma edule, pectinids, Chlamys varia and Aequipecten opercularis; and several clams, e.g., Mercenaria mercenana and Venerupis rhomboïdes. Recreational landings are substantial. The flat oyster, 0. edulis, has been part of human diets for centuries. Natural beds were exploited through the Middle Ages until the last century by...
Tipo: Text
Ano: 1997
URL: http://archimer.ifremer.fr/doc/1997/publication-2391.pdf

Ecophysiological model of growth and reproduction of the black pearl oyster, Pinctada margaritifera: potential applications for pearl farming in French Polynesia
Provedor de dados: 5
Autores: Pouvreau, Stephane; Bacher, Cedric; Heral, Maurice.
A model of bioenergetics of the black pearl oyster (Pinctada margaritifera) was built to simulate growth, reproduction and spawning in suspended culture at field sites in Takapoto lagoon (French Polynesia). This model was based on allometric scaling of physiological functions and scope for growth (SFG) calculations. The input functions were clearance rate (CR, 1 day(-1)), retention efficiency (RE, %) for each kind of particle encountered in suspended matter, pseudofaeces and faeces productions (PF and F, mg C day(-1)), excretion and respiration rate (U and R, mg C day(-1)). The assimilated carbon (i.e., SFG, mg C day(-1)) was partitioned to the three internal state variables (somatic tissue, shell and gonad) according to the asymptotic increase of the...
Tipo: Text
Palavras-chave: Pearl farming; Food depletion; Scope for growth; Carrying capacity; Suspension feeding; Tropical lagoon.
Ano: 2000
URL: http://archimer.ifremer.fr/doc/2000/publication-380.pdf

Composition en éléments azotés minéraux et orgnaiques dissous de l'eau du bassin conchylicole de Marennes-Oléron
Provedor de dados: 5
Autores: Heral, Maurice; Robert, Jean-michel; Truquet, Isabelle; Barbaroux, Olivier; Garnier, Jacqueline; Razet, Daniel.
Values of nitrogen nutrients (ammonia, nitrite and nitrate) are compared with values of total organic nitrogen and urea. In summer, the consumation by micro and macrophytes is added to less important telluric input of nineral nitroge. However, an important provision of organic nitrogen remains. On the contrary, in winter, organic nitrogen does not represent more than 10% of total nitrogen. The autors postulate that populations of oysters are at the starting point of the organic nitrogen production cycle.
Tipo: Text
Palavras-chave: Crassostrea gigas; Biochimical composition; Oysters; Crassostrea gigas; Composition biochimique; Huîtres.
Ano: 1981
URL: http://archimer.ifremer.fr/doc/1981/acte-2940.pdf

Ecophysiological deterministic model for Crassostrea gigas in an estuarine environment
Provedor de dados: 5
Autores: Barille, Laurent; Heral, Maurice; Barilleboyer, Al.
An ecophysiological deterministic model of growth, reproduction and interactions between the bivalve and its estuarine environ ment was established for the Japanese oyster Crassostrea gigas. The environmental variables used in the model are: total particulate matter, particulate organic matter, particulate inorganic matter, chlorophyll, phaeopigments, proteins, lipids and carbohydrates. Rates of clearance, filtration, ingestion, absorption and respiration along with efficiencies of retention, selection and absorption are modelled with endogenous (dry weight of the animal, energy allocation between growth and reproduction) and exogenous variables (temperature, food quality and quantity). The model simulate the temporal evolution of two compartments: somatic...
Tipo: Text
Palavras-chave: Crassoslrea gigas; Croissance; Écophysiologie; Modélisation; Turbidité; Crassostrea gigas; Ecophysiology; Growth; Modelling; Turbidity.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/00038/14892/12219.pdf

Prégrossissement et élevage de palourdes japonaise en marais : technique entre filet
Provedor de dados: 5
Autores: Zanette, Yvan; Heral, Maurice; Peyre, Roger.
Another breeding technique was worked out for Japanese clam Ruditapes philippinarum. It consists in breeding it in a large two-fold net dipped into mud.
Tipo: Text
Palavras-chave: Technique; Elevage; Ruditapes philippinarum.
Ano: 1981
URL: http://archimer.ifremer.fr/doc/1981/acte-2942.pdf

Manipulation of dietary conditions for maximal growth in mussels, Mytilus edulis, from the Marennes-Oléron Bay, France
Provedor de dados: 5
Autores: Hawkins, Ajs; Smith, Rfm; Bougrier, Serge; Bayne, Bl; Heral, Maurice.
Results are presented from laboratory-based experiments in which we investigated short-term responses of Mytilus edulis L. to experimental changes in the amount and composition of suspended seston. Working with large quantities of cultured algae, we have studied feeding behaviour over ranges of food availability and quality that ex tend weil beyond earlier limits. Findings confirm the ability of mussels to selectively reject inorganic particles as pseudofaeces prior to ingestion, thereby enriching the organic content of ingested matter by 30% more than the organic content of natural filtered seston. Our findings also establish acclimation both of selective and absorptive processes, indicating that the extent to which growth of M. edulis can be stimulated...
Tipo: Text
Palavras-chave: Mytilus edulis; Comportement alimentaire; Régulation; Croissance.; Mytilus edulis; Feeding behaviour; Regulation; Maximum growth rate.
Ano: 1997
URL: http://archimer.ifremer.fr/doc/00015/12604/9482.pdf

Effets des sels organiques de tributyletain sur l'huître adulte Crassostrea gigas
Provedor de dados: 5
Autores: Heral, Maurice; Alzieu, Claude; Caux, O.; Razet, Daniel; Garnier, Jacqueline.
The toxicity of organostannic compounds has been demonstrated for the oyster Crassostrea gigas through larval (His &amp; Robert, 1980) and adult stages (Alzieu &amp; al., 1980, 1981). In parallel, these authors demonstrated the accumulation of tin in experimentally contaminated oysters as well as the part played by TBT fluorides in growth disturbance (Héral &amp; al. 1981) and oyster shell deformity (Alzieu &amp; al., 1981). In this work, we precise the TBT fluoride toxic doses causing, after 35 days, a mortality of 100 % at a concentration of 0.5 µgl-1. In addition, the different TBT organic salts (acetate, methacrylate and fluoride) are tested and TBT fluoride appears to be the more toxic. Authors then tackle breathing and ATP measurements as stress...
Tipo: Text
Palavras-chave: Tributyletain; Crassostrea gigas; Toxicité.
Ano: 1983
URL: http://archimer.ifremer.fr/doc/1983/acte-6216.PDF

Evaluation des Risques dus a l'emploi des Peintures Anti-Salissures Dansales Zones Conchylicoles.
Provedor de dados: 5
Autores: Alzieu, Claude; Thibaud, Yves; Heral, Maurice; Boutier, Bernard.
The boats cruising in the oyster growing areas are protected against biofouling by paints which release toxic compounds such as copper oxide and organotins into the water. After an estimation of the inputs of copper and organotins in the "Marennes-Oleron", Arcachon (Atlantic)    and Thau (Mediterranean Sea) areas, their influence on larval fixation is discussed, taking into account the tributyltin toxicity against D larvae of Crassostrea gigas. Laboratory experiments have demonstrated that tributyltin produces morphological abnormalities of the shell and increases tin levels in tissues, interfering with copper and zinc metabolism. The influence of yacht ports on oyster growth and shell morphology, has been demonstrated in the field. The use of...
Tipo: Text
Palavras-chave: Crassostrea gigas; Oyster culture; Abnormalities; Shells; Growth; Paints; Antifouling substances; Pollution effects.
Ano: 1980
URL: http://archimer.ifremer.fr/doc/1980/publication-1905.pdf

Diversification de la production : culture de palourdes sur estran, résultats années 84-85
Provedor de dados: 5
Autores: Goulletquer, Philippe; Prou, Jean; Heral, Maurice.
Following the development of net protection techniques (1980), Japanese clam Ruditapes philippinarum farms develop in the ponds of Charente-Maritime. The county production for 1984 is about 100 tonnes, for a turnover of 4.5 Million Francs. To this day, farmers cultivating clams in ponds over a full cycle get better growth results during the first year. The size of 24 mm is obtained with a density of 200 individuals per square metre. However, due to the type of water input in ponds and to the limited primary production developing in the latter, it appears that biomasses in farms during the second year should not be greater than 0.5 to 1 kg per m² (30 to 50 clams per m²). Thus, the development of clam culture in marsh areas comes to a halt, as farmers are...
Tipo: Text
Palavras-chave: Marennes Oléron; Mortalité; Biomasse; Croissance pondérale; Croissance linéaire; Biométrie; Elevage; Ruditapes philippinarum; Palourdes.
Ano: 1985
URL: http://archimer.ifremer.fr/doc/1985/rapport-3840.PDF

Ecotoxicological effects of organotin compounds on oyster culture
Provedor de dados: 5
Autores: Alzieu, Claude; Heral, Maurice.
The toxic effect of trialkyltin compounds is used in antifouling paints to protect vessels against biofouling organisrns. Tributyltin oxide (TBTO) or fluoride (TBTS) leaches by diffusion from the paint layer into the seawater. Trialkyltin compounds in aqueous solutions are resistant to hydrolysis and biodegradation, but are rapidly converted into diakyl, monoalkyl  and  inorganic tin by UV irradiation.  As inhibiting agents of the oxidative phosphorylation, organotin compounds are extremely dangerous for aquatic organisms such as molluscs. The following estimated toxicity levels for Crassostrea gigas oyster larvae have been put forward : at 100 µg.l(1) the fecondation is inhibited, at 10 µg.l1 the already of 20 % of the eggs  is affected larval development...
Tipo: Text
Palavras-chave: Toxicity; Fluoride; Tribultyltin oxide; Toxic effect; Oysters; Crassostrea gigas.
Ano: 1984
URL: http://archimer.ifremer.fr/doc/1984/publication-2931.pdf

Oyster production in Europe and in the Chesapeake Bay
Provedor de dados: 5
Autores: Heral, Maurice.
This report has been achieved during a work as short-term consultant in Chesapeake Biological Laboratory (University of Maryland) in the Laboratory of Prof. B. J. Rothschild, for a period from July 7 to August 7 1989 and at Ifremer Laboratory of La Tremblade. The terms of reference of the consultance were : to compare the oyster fishery researches between the Chesapeake Bay and Europe, particularly in reference to the French coast. To evaluate the on-going Chesapeake Bay oyster stock assessment project and to provide its comments and recommendations. To work on spat settlement in the Bay. This study was funded by the National Oceanic and Atmospheric Administration, by the Maryland Department of Natural Resources under contract F 1666-89-008 and by the...
Tipo: Text
Palavras-chave: Oyster culture; Oyster production; European countries; Maryland; Chesapeake Bay; Causes; Perspectives.
Ano: 1989
URL: http://archimer.ifremer.fr/doc/00043/15411/12770.pdf

Modélisation de l'écosystème du bassin de Marennes-Oléron (Rapport 1991)
Provedor de dados: 5
Autores: Raillard, Olivier; Razet, Daniel; Prou, Jean; Heral, Maurice.
Les expérimentations en continu sur le site du Chapus au centre du bassin de Marennes-Oléron pendant le mois de mai 1990 ont permis de déterminer le comportement des huîtres (filtration et ingestion). Dans le bassin de Marennes-Oléron les huîtres sont toujours au-dessus du seuil de production de pseudofeces qui régulent la qualité de nourriture ingérée. Ces résultats démontrent par ailleurs qu'il existe nettement un tri du matériel particulaire en suspension. Les huîtres rejettent préférentiellement le matériel minéral dans les pseudofeces alors que le matériel qui transite dans le tractus digestif est enrichi en matière organique. Un modèle trophique des huîtres a ainsi pu être établi avec de nouvelles lois de tri de la matière particulaire. Parallèlement...
Tipo: Text
Palavras-chave: Séries en continu; Turbidité; Phytoplancton; Physiologie huître Crassostrea gigas; Modèle de croissance; Modèle de remise en suspension.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/00095/20635/18266.pdf

Evalution du bilan énergétique de l'huître creuse, Crassostrea gigas, en baie de Marennes-Oléron (France)
Provedor de dados: 5
Autores: Soletchnik, Patrick; Goulletquer, Philippe; Heral, Maurice; Razet, Daniel; Geairon, Philippe.
This ecophysiological study was conducted on the Japanese oyster (Crassostrea gigas) reared in Marennes-Oléron bay (France), in May 1992. Measurements were achieved using natural food conditions on three different days (a, b, c) at different tide levels (coefficient of 49, 57, and 88). Total particulate matter was continuously monitored with a micro-computer and a turbidimeter probe. The "consumption" function was calculated using a new formula allowing for particulate leakage prior to the pre-ingestive particle sorting. This particle leakage represents a passive loss of particles flowing through the branchial filter. Comparisons of the consumption and absorption rates of organic matter and chlorophyll a showed significant differences between seston...
Tipo: Text
Palavras-chave: Crassostrea gigas; Consumption rate; Selection efficiency; Absorption rate; Energetic budget; Organic matter; Chlorophyll alpha; Marennes-Oleron bay.
Ano: 1996
URL: http://archimer.ifremer.fr/doc/1996/publication-3086.pdf

Variations saisonnières in situ de la production et de la composition des biodépots de trois mollusques estuariens (Mytilus edulis, Crassostrea gigas, Crepidula fornicata)
Provedor de dados: 5
Autores: Deslous-paoli, Jean-marc; Sornin, Jean-marc; Heral, Maurice.
The biodeposition was quantified on the field with sediment traps. All over the year, the biodeposition was the lowest for Crepidula fornicata. Mytilus edulis rejected more biodeposits during winter, and Crassostrea gigas during spring and autumn. The percentage of organic matter sonsumed and digested was higher during summer. The constituttive elements of the digested organic matter was not always the same, all over the year. The energy content of the digest fraction was higher in spring. For Mytilus edulis the ration intake was higher in winter and spring, related with the gametogenetic ans spawning period. An analysis of the mineral constutents of the natural food was made.
Tipo: Text
Palavras-chave: Crepidula fornicata; Crassostrea gigas; Mytilus edulis; Digestibility; Biodeposition; Crepidula fornicata; Crassostra gigas; Mytilus edulis; Digestibilité; Biodéposition.
Ano: 1987
URL: http://archimer.ifremer.fr/doc/1987/publication-2691.pdf

Gestion des bassins conchylicoles
Provedor de dados: 5
Autores: Heral, Maurice; Prou, Jean; Sauriau, Pierre-guy; Goulletquer, Philippe.
The excess of farmed mollusc biomass in some French shellfish-farming basins (Marennes-Oléron basin, Isle of Ré, Isle of Bourgneuf) has been clearly highlighted. This manifests itself as a decrease of growth consistency of the molluscs and an increase in chronic mortality rates not linked to pathogenic agents. To this excess of farmed biomass are added the biomass of oysters or "wild" mussels or biomass linked to abandoned concessions.
Tipo: Text
Palavras-chave: Estimation; Croissance; Biomasse; Conchylicultre.
Ano: 1995
URL: http://archimer.ifremer.fr/doc/1995/acte-3084.pdf

Modèle énergétique uniboite de la croissance des huîtres (Crassostrea gigas) dans le bassin de Marennes-Oléron
Provedor de dados: 5
Autores: Bacher, Cedric; Heral, Maurice; Deslous-paoli, Jean-marc; Razet, Daniel.
The growth of oysters (Crassostrea gigas) is modeled in order to study the trophic capacity of the Bay of Marennes Oléron. Total seston and amount of protids, lipids, and carbohydrates converted to energy are the environmental factors taken into account. Time series of these variables are derived during 2 yr with a daily time step from a linear regression including the tidal velocity, the height of the water column, and the wind velocity. A model of the energetic budget based on assimilation and respiration terms and depending on the previous time series is run to simulate the individual growth of an oyster. The knowledge of the number of oysters, the flow of water entering the bay, and the volume of the bay allows us then to estimate that 7% of the...
Tipo: Text
Palavras-chave: Marennes Oléron; Crassostrea gigas; Huîtres; Croissance; Modélisation; Marennes Oleron bay; Crassostrea gigas; Oysters; Growth; Modelisation.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/1991/publication-3051.pdf

In situ estimations of uptake and release of material by oysters in the Bay of Marennes-Oléron (France)
Provedor de dados: 5
Autores: Zurburg, Wouter; Smaal, Aad; Heral, Maurice; Dankers, Norbert.
The uptake and release of material by oysters (Crassostrea gigas) in the intertidal zone were estimated in situ in the Bay of Marennes-Oléron (France) in spring and autumn. 10 m long plexiglass tunnels were placed over small tables with bags containing oysters or empty oyster shells (control). Although in the very turbid conditions of the water column sedimentation of suspended particulate material could be observed in control experiments, higher fluxes (uptake) of seston, POC and PON and especially chlorophyll occurred in the presence of live animals. Release of dissolved nutrients was not evident from the tunnel with oysters, which is in contrast with studies in other areas with bivalves. This is ascribed to limited mineralization of biodeposits as an...
Tipo: Text
Palavras-chave: Chlorophyll; Seston; Oysters; Nutrient release; Material uptake.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/1994/publication-6842.PDF

Feeding behaviour of the mussel, Mytilus edulis : responses to variations in quantity and organic content of the seston
Provedor de dados: 5
Autores: Bayne, Bl; Iglesias, Jip; Hawkins, Ajs; Navarro, E; Heral, Maurice; Deslous Paoli, Jean-marc.
Mussels were fed four concentrations of seston (between 0•99 and 10•3mgtotalseston P), comprising three levels of organic content (71•9, 63•6 and 40•8%), made up from natural silt and two species of cultured phytoplankton. Two of the seston concentrations were below, and two above, the threshold at which pseudofaeces were produced. Measurements of physiological traits (filtration rates, pseudofaeces production, selection efficiency, absorption efficiency, absorption rates and rates of oxygen consumption) were made after 2 days and, for two of the seston concentrations, also after 12 days. When fed at a high concentration of seston of low organic content, the mussels increased their filtration rate, rejected a higher proportion of filtered material as...
Tipo: Text
Ano: 1993
URL: http://archimer.ifremer.fr/doc/1993/publication-3069.pdf

Regimes Alimentaires et Modifications des Structures Mandibulaires (Leach) (Decapoda, Palaemonidae) Etudiees a l'Aide du Microscope Electronique a Balayage.
Provedor de dados: 5
Autores: Heral, Maurice; Saudray, Yves.
The object of this study is to complete the knowledge of the mandibles structure in a eucarid: P. varians (Leach). Its rearing has permitted the study, parallell to the evolution of the mandibles structure, of the diet of larvae and adults.
Tipo: Text
Palavras-chave: Palaemonetes varians; Larval development; Adults; Larvae; Diets.
Ano: 1979
URL: http://archimer.ifremer.fr/doc/1980/publication-1939.pdf

Effect of the density of the culture and the depth on the seasonal variation of the biochemical composition of Crassostrea virginica in patuxent river (Chesapeake Bay)
Provedor de dados: 5
Autores: Prou, Jean; Heral, Maurice; Goulletquer, Philippe; Forget, Maïté; Bougrier, Serge; Razet, Daniel.
The project of cultivation of oyster has been designed to evaluate the growth rate, the mortality, the reproductive effort, production and biochemical composition of the oyster function of the density and the depth. This plan was intended: - to build model of growth rate, - to demonstrate the action of the different parameters on growth rate (temperature, food effect...), - to evaluate the density effect to see if the available food could be a limiting factor, - to estimate the effect of the depth joined to the impact of the high turbidity near the bot tom, - to detect the mortality related to the prevalence of diseases.   The project began in July 1989 by dredging 20 000 small oysters at the mouth of the Patuxent River near Cove Point. Three experimental...
Tipo: Text
Palavras-chave: Physiology; Seasonal variation; Biochemical composition; Density; Crassostrea virginica; Cheseapeake Bay.
Ano: 1991
URL: http://archimer.ifremer.fr/doc/00200/31104/29503.pdf

Influence des Peintures Antisalissures a Base d'Organostanniques sur la Calcification de la Coquille de l'Huitre Crassostrea gigas.
Provedor de dados: 5
Autores: Alzieu, Claude; Heral, Maurice; Thibaud, Yves; Dardignac, Marie-jose; Feuillet, Michèle.
Experiments in oyster-breeding areas where oyster Crassostrea gigas suffers from anomalies of calcification, show an obvious correlation between the importance of the malformation of shells and the vicinity of port areas where a great number of boats usually stay. Organotin compounds contained in antifouling paints, and more precisely Tributyltin fluoride (TBTF) induce, in experimental environment, similar anomalies to those observed in natural environment. The amounts of total tin in the tissues of oysters living in the vicinity of spots where organotin products are brought in, can reach high values, though they appear to decrease rapidly whereas the environmental contamination lessens. The authors suggest that results of organotin upon the mechanisms of...
Tipo: Text
Palavras-chave: Crassostrea gigas; Pollution effects; Toxicity; Calcification; Fouling control; Paints.
Ano: 1981
URL: http://archimer.ifremer.fr/doc/1981/publication-1898.pdf

Biochemical composition and energy value of Crassostrea gigas (Thunberg) cultured in the bay of Marennes-Oleron
Provedor de dados: 5
Autores: Deslous-paoli, Jean-marc; Heral, Maurice.
In the bay of Marennes-Oleron the dry flesh of Crassostrea gigas ranged from 29 to 52% proteins, 10 to 23% ash, 6 to 20% lipids and 0 to 4% carbohydrates of which 48.3 ± 21.6% were glycogen. The energy value ranged from 18.84 to 23.47 joule. Mg(-1) ash free dry weight (mean 20.27 J. mg(-1). Reproductive effort varied from 17.8 to 55.9% dry weight for males, and 43.1 to 61.9% for females during the first and third year of reproduction respectively. A high energy value for female gametes (23.47 to 26.24 J. mg(-1) dry tissue) was mainly due to a higher level of lipids (17.3 to 23% of dry tissue) in female gametes as compared to that in male gametes (5.9 to 12.3% of dry tissue). During the period of mass-loss which began in October and finished in March, the...
Tipo: Text
Palavras-chave: Crassostrea gigas; Winter loss of flesh; Reproductive effort; Energy value; Biochemical composition; Crassostrea gigas; Amaigrissement hivernal; Effort de reproduction; Valeur énergétique; Composition biochimique.
Ano: 1988
URL: http://archimer.ifremer.fr/doc/1988/publication-2872.pdf

Seston dynamics and bivalve feeding in the Bay of Marennes-Oléron (France)
Provedor de dados: 5
Autores: Zurburg, Wouter; Smaal, Aad; Heral, Maurice; Dankers, Norbert.
Within the framework of an investigation into the carrying capacity of the Bay of Marennes-Oléron (France) for bivalve culture, the in situ uptake of suspended particulate material by oysters (Crassostrea gigas) and mussels (Mytilus edulis) was determined in experiments with benthic ecosystem tunnels. Very high fluctuations in seston quantity and quality were observed within and between tidal cycles. The percentage of organic carbon was inversely related to seston quantity at low concentrations. Organic carbon was diluted by resuspension of material rich in inorganic matter. At high seston concentrations a constant level of about 2% organic carbon was found. The CIN ratio was relatively constant throughout the seasons and fairly low (6.5 to 8.4). Owing to...
Tipo: Text
Palavras-chave: Microphytobenthos; Chlorophyll; Feeding; Mussel; Oyster; Seston quality; Seston load.
Ano: 1994
URL: http://archimer.ifremer.fr/doc/1994/publication-6843.PDF

Retention efficiency in oyster Crassostrea gigas exposed to variable food quantity and quality
Provedor de dados: 5
Autores: Barille, Laurent; Prou, Jean; Heral, Maurice; Bougrier, Serge.
Relative retention efficiency (Er%) of Crassostrea gigas was estimated in the laboratory with 7 diets consisting of algae and silt. Total particulates varied from 1.34 mg/l in natural sea water to 27.65 mg/l in natural sea water enriched with silt. It was also calculated from field experiment to get high concentration of seston up to 66 mg/l. It appeared that Crassostrea gigas did not adjust its retention according to the food quality and the gill porosity was controlled by the concentration of particulate matter. In low seston load (1.34 mg/l) the oyster showed no change in retention for particles larger than 3-4 µm (Equivalent Spherical Diameter, ESD) but at the highest concentration (66 mg/l) it could only retain with a maximum efficiency particles...
Tipo: Text
Palavras-chave: Crassostrea gigas; Dietary quality; Particle concentration; Physiological model; Retention efficiency.
Ano: 1992
URL: http://archimer.ifremer.fr/doc/00100/21096/18721.pdf

Les substances dissoutes dans les eaux du Bassin Marennes-Oléron et dans les eaux interstitielles de ses parcs conchylicoles : résultats préliminaires
Provedor de dados: 5
Autores: Feuillet, Michelle; Heral, Maurice; Razet, Daniel; Guerguin, F.; Abrioux, M. F.
The bassin of Marennes-Oléron, estuary medium shows very strong rates in total dissolved carbon and more particularly in sugars. It appears that the MOD could be directly used by oysters. There energy contribution could be enough for breeding Crassostrea gigas.
Tipo: Text
Palavras-chave: MOD; Substances organiques dissoutes; Marennes Oléron; Crassostrea gigas; Huîtres; Nutrition.
Ano: 1979
URL: http://archimer.ifremer.fr/doc/1979/acte-3000.pdf

Transferts énergétiques entre l'huître Crassostrea gigas de 1 an et la nourriture potentielle disponible dans l'eau d'un bassin ostréicole
Provedor de dados: 5
Autores: Deslous-paoli, Jean-marc; Heral, Maurice.
A paraIleI study of the available energy in the water and of the energy balance of one year old Crassostrea gigas has been made in Marennes-Oleron. Also, from the 32.95 \06 Kcal/m2 that goes through a waterspout of 0,1 m (5.96 \06 Kcal/m2 from phytoplancton, and 64.1 102 Kcal/m2 for the bacteria), an average of 0.19 70 is used by the oyster population. 5 343 Kcal of that annual consummate energy (20 383 Kcal) are assimilated, and 15 035 Kcal (73.8 70) are rejected as feces pseudofeces. From the assimilated energy, 4 317 Kcal (80.8 %) was available for the metabolism and 19.2 % for production of tissue (567 Kcal), shell (281 Kcal) and gametes (182 Kcal). However in the winter the production efficiency are negative ant it is considered that the overload in...
Tipo: Text
Palavras-chave: Marennes Oleron estuary; Crassostra gigas; One year old; Energetic flow; Estuaire de Marennes Oléron; Crassostrea gigas de 1 an; Transfert énergétique.
Ano: 1984
URL: http://archimer.ifremer.fr/doc/1984/publication-2930.pdf

Reproduction et recrutement de Mytilus edulis L. cultivée sur les bouchots du bassin de Marennes-Oléron
Provedor de dados: 5
Autores: Boromtharanat, S; Deslous-paoli, Jean-marc; Heral, Maurice.
Observations on the gonads of 50 mm mussels, made during 1983 and 1984, showed that the onsert of gametogenesis occured during September and that the gonads reached maturity in December. Spawning took place from early February to April at temperatures from 10 to 12°C. The flesh had a high water content at the beginning of the spawning period. The pelagic live of the larvae lasts about 30 days with settlement occurring in June when some 90 and 100 spats settle on 1 cpm of rope per day. The intensity of recruitment was 56.10(4) and 722.10(4) larvaes on rope corresponding to a square meter during 1983, and between 28.10(4) and 81.10(4) during 1984.
Tipo: Text
Palavras-chave: Crawl; Recruitment; Reproduction; Mytilus edulis; Bouchot; Recrutement; Reproduction; Mytilus edulis.
Ano: 1987
URL: http://archimer.ifremer.fr/doc/1987/publication-2865.pdf