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Registros recuperados: 86 | |
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Bacher, Cedric. |
A model of the growth of cultivated oyster in the Marennes-Oléron bay was developped to assess the influence of the nutrients input and of the amount of oysters on the growth performance (Railiard. 1991). The ecosystem main characteristics are: - short residence time of the water. - high turbidity level, depending on the season, tidal level, bathymetry, currents and wind. The turbidity acts on the primary production through light limitation and on oyster production as a food dilution factor. - presence of high density cultivated areas on mid-tidal flats. The amount of oysters is ranging between 80 000 and 110 000 tons according to the year. - spatial variability of the biological and physical features. - coupling effects of the physic process (transport,... |
Tipo: Text |
Palavras-chave: Ecosystem model; Oyster; Crassostrea gigas; Nitrogen cycling; Marennes Oleron Bay; Charente Maritime. |
Ano: 1993 |
URL: http://archimer.ifremer.fr/doc/00102/21300/18914.pdf |
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Sauriau, Pierre-guy; Bacher, Cedric. |
Stock assessement of wild soft-bottom mol/uses has been part of a general approach to shellfish management in oyster farming in Marennes-Oleron Bay. A sampling survey is described as a stratified random sampling after optimum allocation of the sample sire in each stratum. The aim of this study is ta ilIustrate the use of kriging techniques in the case of suspension-feeders. Regarding suspension-feeding molluscs. trophic competitors of the oyster Crassostrea gigas the whole stratified design produced an estimation with a precision around 25%. Then the geostatistical technique. i.e. kriging was used to depict the spatial and variability patterns of several trophic groups. The biomass data are expressed in ash-free. dry-weight units. In addition, the... |
Tipo: Text |
Palavras-chave: Marennes Oléron; Crassostrea gigas; Krigeage; Suspensivore; Echantillonnage stratifié; Peuplement benthique. |
Ano: 1991 |
URL: http://archimer.ifremer.fr/doc/1991/publication-3055.pdf |
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Bacher, Cedric; Gangnery, Aline; Cugier, Philippe; Mongruel, Remi; Strand, Oivind; Frangoudes, Katia. |
The general purpose of assessment is to provide decision-makers with the best valuable data, information, and predictions with which management decisions will be supported. Using case studies taken from four scientific projects and dealing with the management of marine bivalve resources, lessons learned allowed identifying some issues regarding assessment approaches. The selected projects also introduced methodological or institutional frameworks: ecosystem approach to aquaculture (EAA), system approach framework (SAF), marine spatial planning (MSP), and valuation of ecosystem services (ES). The study on ecosystem services linked ES to marine habitats and identified ES availability and vulnerability to pressures. The results were displayed as maps of... |
Tipo: Text |
Palavras-chave: Ecosystem services; Marine spatial planning; Ecosystem approach to aquaculture; System approach; Modeling; Stakeholder involvement. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00470/58138/60608.pdf |
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Mazurie, Joseph; Soletchnik, Patrick; Ropert, Michel; Fleury, Pierre-gildas; Auby, Isabelle; Maurer, Daniele; Bacher, Cedric. |
Monitoring of Crassostrea gigas performances, from two year-classes, during 12 years, in various French shellfish farming areas have revealed great inter-annual and inter-sites differences in reproduction, growth, mortality or quality of oysters (meat content, Polydora infestation...). The presentation attempts to highlight how a comparative analysis of existing temporal or spatial data on molluscs, water quality, geography or meteorogoly may help to better understand and manage shellfish ecosystems. The range of hydrobiological conditions (food availability, turbidity, temperature...) recorded at national, pluriannual scale, in relation to shellfish performances, enlarges the base of such relationship. However, undirect causative factors, either natural... |
Tipo: Text |
Palavras-chave: Climatic modulation; Hydro geography; Reproduction; Growth; Spatial differences; Water quality; Mortality; Shellfish productivity. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/acte-3318.pdf |
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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 |
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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 |
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Samain, Jean-francois; Ropert, Michel; Bedier, Edouard; Soletchnik, Patrick; Mazurie, Joseph; Le Coz, Florence; Blin, Jean-louis; Mille, Dominique; Pajot, Régis; Haffray, Patrick; Bacher, Cedric; Grangere, Karine; Grangere, Karine; Pouvreau, Stephane; Bourles, Yves; Gohin, Francis; Woerther, Patrice; Boudry, Pierre. |
Summer mortality has been reported in the Pacific oyster, Crassostrea gigas, for many years in Japan, US and Europe. It affects both adults and juveniles and the causes of this phenomenon are complex. Environmental, physiological or pathological putative causes were studied all over the world. Recently, the MOREST project ((MORtalitEStivale) a multidisciplinary project (2001-2005) focused on his problem led to a better understanding of this phenomenon in France. The results showed in these geographical conditions, the main interactions between the oysters, their environment and certain pathogens. |
Tipo: Text |
Palavras-chave: Interaction model; Environmental parameters; Summer mortality; Crassostrea gigas; Pacific oyster. |
Ano: 2006 |
URL: https://archimer.ifremer.fr/doc/2006/acte-3476.pdf |
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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 |
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Bacher, Cedric; Grant, Jon; Hawkins, Anthony; Fang, Jianguang; Zhu, Mingyuan; Besnard, Melanie. |
Sungo Bay (China) has a mean depth of 10 m, a total area of 140 km(2) and is occupied by several types of aquaculture, whilst opening to the ocean. The production of scallops (Chlamys farreri) cultured on long lines is estimated to exceed 50 000 tonnes (total weight) per year. Selection of sites for scallop growth and determination of suitable rearing densities have become important issues. In this study, we focused on the local scale (e.g. 1000 m) where rearing density, food concentration and hydrodynamics interact. We have developed a depletion model coupling a detailed model of C. farreri feeding and growth and a one-dimensional horizontal transport equation. The model was applied to assess the effect of some environmental parameters (e.g. food... |
Tipo: Text |
Palavras-chave: Chlamys farreri; Transport equation; Rearing density; Energy budget. |
Ano: 2003 |
URL: https://archimer.ifremer.fr/doc/2003/publication-570.pdf |
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Bacher, Cedric; Chai, Ai-ling; Goulletquer, Philippe. |
The krlging technique Is now employed ln more and more fields: mlnlng (Journel. 1977), hydrology (Delhomme, 197B; Shamsi et al" 1988; Dingman et al" 1988), fishery (Conan, 1989) and ecology (Robertson, 1987; Schotzko and O'Keeffe, 1989, 1990). Recent developments of the mathematlcal theory tend to extend the number of applications where Il may be used. Baslcally defined for the case of a statlonary spatial process, It now encompasses more general processes assuming less and less strong hypotheses (Intrinsic hypothesls, Intrlnsic generalised hypothesis, disjunctive krlglng). In its most general formulation, it allows to study the spatial structure of a process including large scale or local trends. The basic idea remains to take Into account the spatial... |
Tipo: Text |
Palavras-chave: Kringing technique; Stock assessment; Oysters; Crassostrea virginica; Chesapeake Bay. |
Ano: 1991 |
URL: http://archimer.ifremer.fr/doc/00200/31110/29518.pdf |
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Guarini, Jean-marc; Blanchard, Gf; Gros, Philippe; Gouleau, Dominique; Bacher, Cedric. |
In the present paper, we list and document the relevant behavioral and physiological processes controlling primary productivity of epipelic microalgae on intertidal mudflats in order to develop a simplified model. We first propose, in an attempt to characterize the 'photosynthetically active biomass' of the epipelic community, a new approach to describe the photic environment at the sediment surface, by substituting a discrete a-layer model in place of continuous vertical light distribution. This concept thus allows us to build a functional representation of the distribution of the photosynthetically active biomass in the sediment and, by then integrating the light and temperature forcing of the latter biomass, to predict the dynamics of the whole epipelic... |
Tipo: Text |
Palavras-chave: Microphytobenthos; Intertidal mudflat; Primary production; Dynamic model; Migratory rhythm; Ecophysiological response. |
Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/00000/10540/7601.pdf |
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Bacher, Cedric; Gangnery, Aline. |
We successfully tested a Dynamic Energy Budget (DEB) model of the oyster Crassostrea gigas using published environmental data and growth data collected in Than lagoon (France). Estimates of most DEB parameters were based on independent datasets and only two parameters were calibrated using our datasets: the shape parameter, which was used to convert body volume into shell length, and the half-saturation coefficient, which controlled the functional response of assimilation to food concentration, represented by chlorophyll-a concentration. The DEB model proved to be robust and generic: it was able to reproduce oyster growth in Than lagoon and other ecosystems. We also assessed population dynamics by coupling DEB equations and an Individual Based Model (IBM)... |
Tipo: Text |
Palavras-chave: Thau Lagoon; Growth variability; Harvested production; Dynamic Energy Budget; Crassostrea gigas. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2329.pdf |
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Registros recuperados: 86 | |
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