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| Registros recuperados: 87 | |
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| Bodin, Nathalie. |
| The aim of this study was to evaluate the seasonal variations of six biomarkers on Mytilus galloprovincialis, using comparison with physiological index and chemical contamination levels on two sites of Mediterranean sea. The seasonal variations of acetylcholinesterase (AChE), DNA adducts, benzo(a)pyrene hydroxylase (BPH), heat-shock proteins (HSP), metallothioneins (MT) and multixeniobiotic proteins (MXR) were estimated over a two-year period, on mussels which were sampled in Carteau (original site) and La Fourcade (transplanted organisms). Carteau, an industrial site, presents higher contamination levels (HAP, PCB, heavy metals) than La Fourcade, an urban area. The PAH profiles underline a strong spatio-temporal variability of levels and sources of... |
| Tipo: Text |
Palavras-chave: Biomonitoring; Mytilus galloprovincialis; Biomarqueurs; Variations saisonnières; Biomonitoring; Mytilus galloprovincialis; Biomarkers; Seasonal variations. |
| Ano: 2002 |
URL: http://archimer.ifremer.fr/doc/00443/55499/57042.pdf |
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| Raybaud, V.; Nival, P.; Mousseau, L.; Gubanova, A.; Altukhov, D.; Khvorov, S.; Ibanez, F.; Andersen, V.. |
| Short term changes in zooplankton community were investigated at a fixed station in offshore waters of the Ligurian Sea (DYNAPROC 2 cruise, September-October 2004). Mesozooplankton were sampled with vertical WPII hauls (200 mu m mesh-size) and large mesozooplankton, macrozooplankton and micronekton with a BIONESS multinet sampler (500 mu m mesh-size). Temporal variations of total biomass, species composition and abundance of major taxa were studied. Intrusions of low salinity water masses were observed two times during the cruise. The first one, which was the most intense, was associated with changes in zooplankton community composition. Among copepods, the abundance of Calocalanus, Euchaeta, Heterorhabdus, Mesocalanus, Nannocalanus, Neocalanus,... |
| Tipo: Text |
Palavras-chave: Ligurian sea; Wind events; Phytoplankton community; Vertical distributions; Seasonal variations; English channel; Spring bloom; Oregon coast; Variability; Copepods. |
| Ano: 2008 |
URL: https://archimer.ifremer.fr/doc/00208/31975/30410.pdf |
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| Maguer, Jf; Lecorre, P; Madec, C. |
| Seasonal changes in inorganic (NH4+; NO3-; NO2-) and organic (urea) nitrogen uptake were studied with N-15 as a tracer at a shallow station (depth: 22 m) in permanently well-mixed waters of the Western English Channel. Uptake of all the four nutrients was maximum in spring. Nitrate uptake accounted for a third of the total during spring phytoplankton growth, but decrease in summer. This decrease was related to the low ambient nitrate concentrations in early summer and to an inhibition of uptake by high concentrations in late summer. Ammonium was taken up in significant amounts from the beginning of spring (46 % of total uptake), increasing to 59 % in summer. In contrast with nitrate, ammonium concentrations during summer were sufficiently high to saturate... |
| Tipo: Text |
Palavras-chave: Nitrogen; Uptake; Seasonal variations; Western English Channel. |
| Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/00096/20723/18360.pdf |
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| Plus, Martin; Auby, Isabelle; Verlaque, Marc; Levavasseur, Guy. |
| The main photosynthesis and respiration parameters (dark respiration rate, light saturated production rate, saturation irradiance, photosynthetic efficiency) were measured on a total of 23 macrophytes of the Than lagoon (2 Phanerogams, 5 Chlorophyceae, 10 Rhodophyceae and 6 Phaeophyceae). Those measurements were performed in vitro under controlled conditions, close to the natural ones, and at several seasons. Concomitantly, measurements of pigment concentrations, carbon, phosphorous and nitrogen contents in tissues were performed. Seasonal intra-specific variability of photosynthetic parameters was found very high, enlightening an important acclimatation capacity. The highest photosynthetic capacities were found for Chlorophyceae (e.g. Monostroma obscurum... |
| Tipo: Text |
Palavras-chave: Thau lagoon; Phaeophyceae; Rhodophyceae; Chlorophyceae; Seagrasses; Seasonal variations; Oxygen method; Macrophytes; Light response curve; Photosynthesis. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-465.pdf |
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| 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 |
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| Chopin, T; Floc'H, J; Bodeau, B; Penot, M. |
| Phosphorated nutrition of the red alga Chondrus crispus Stackh. is studied is two morphologically very dissimilar forms of the thallus. Phosphorus measurements, which were monthly carried out at different parts of the alga, showed first that the distribution of this element is not homogeneous along the thallus, and second that seasonal variations occur. It is suggested that the classical polymorphism of the species can be taken into account as concerns its physiology. Besides, from absorption and exsorption experiments which were performed with super(32)P as a tracer, it is shown that the high concentration factor of phosphorus in the alga as compared to the environmental seawater (up to 17.9 x 10 super(4)) can be explained as an effect of metabolic process. |
| Tipo: Text |
Palavras-chave: Chondrus crispus; Algae; Distribution; Metabolism; Seasonal variations; Food absorption; Phosphorus; Plant nutrition. |
| Ano: 1983 |
URL: http://archimer.ifremer.fr/doc/1983/acte-1175.pdf |
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| Gaudy, R; Pagano, M. |
| The zooplankton of an eutrophic brackish lagoon (Etang de Berre), near Marseille (France) was studied during an annual cycle. It was characterized by large populations of a pelagic copepod (Acartia tonsa ). Grazing on natural particles by this species was investigated. Adults were able to use an extended range of particle sizes, but showed selectivity for particles concentration was observed (14 mu m). Temperature and particles concentration appear to modify the selectivity behavior. Juvenile stages could also catch particles of various size but did not show the same selectivity for the peak particles as adults. Daily food ration was high comparatively to open-sea copepods. Taking into account several results obtained on food ration, egg production and... |
| Tipo: Text |
Palavras-chave: Copepoda; Lagoons; Energy budget; Seasonal variations; Particle concentration; Zooplankton; Food availability; Temperature effects; Nutrition. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-1526.pdf |
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| Plantecuny, M; Bodoy, Alain. |
| In order to estimate energetic relationship, microphytic and benthic bivalve levels of a shallow (1.5 m), sandy ecosystem near Marseille (Gulf of Fos, Southern France) were sampled monthly during 1.5 year, in two sites differing by their wave exposure. In the sheltered area, the bivalve Ruditapes decussatus was the dominant species, while another bivalve, Donax trunculus , was found in the open, wave exposed site. Chlorophyll a and primary production of the phytoplankton and the microphytobenthos, as well as population dynamic, growth and biochemical composition of bivalves (lipids, proteins and carbohydrates) were monitored. |
| Tipo: Text |
Palavras-chave: Ruditapes decussatus; Bivalvia; Periphyton; Phytoplankton; Biochemical composition; Growth; Marine molluscs; Hydrodynamics; Seasonal variations; Primary production; Trophic relationships. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-1528.pdf |
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| Guidetti, Paolo; Bussotti, Simona. |
| The fish fauna of a shallow meadow composed by the seagrasses Cymodocea nodosa and Zostera noltii was studied in the Gulf of Olbia (NE Sardinia, Italy; Western Mediterranean). Visual censuses were conducted monthly from August 1995 to August 1996. Environmental variables for water temperature, salinity and seagrass shoot density were collected on each sampling occasion. A total of 23 fish species from eight families were recorded. Planktivorous species (Atherinids) numerically dominated the fish community, followed by necto-benthic fish, chiefly Labrids and Sparids. There was no discernible trend in total fish density. Species richness, diversity, evenness and density of necto-benthic species, instead, displayed a distinct seasonal pattern, higher Values... |
| Tipo: Text |
Palavras-chave: Ichtyofaune; Phanérogames marines; Variations seasonnières; Mediterranée; Fish fauna; Seagrasses; Seasonal variations; Mediterranean. |
| Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/00323/43373/42838.pdf |
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| Hoppe, H. |
| Extracellular enzymes mediate the decomposition of polymeric organic compounds in natural waters. In many cases these enzymes comprise a component linked to the bacterial fraction of the aquatic community and react in close association with these cells. An annual survey of microbial activities in a brackish water fjord exhibited an excellent correlation between V sub(m) of proteases (ability to split the substrate analogue methylumbelliferyl-leucine) and V sub(m) as well as T sub(R) for leucine uptake by microorganisms. Hydrolysis rates (H sub(R)) for the decomposition of naturally occurring competitive substrate analogues of the model substrates (methylumbelliferyl-(MUF)-leucine, MUF- alpha -D-glucose, MUF-N-acetyl-glucosamine, MUF-phosphate) drastically... |
| Tipo: Text |
Palavras-chave: Biogeochemistry; Fjords; Bacteria; Brackishwater environment; Seasonal variations; Dissolved organic matter; Interspecific relationships; Hydrolysis; Enzymes. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-952.pdf |
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| Delaporte, Maryse; Moal, Jeanne; Soudant, Philippe; Lambert, Christophe; Pouvreau, Stephane; Enriquez, Martha; Degremont, Lionel; Soletchnik, Patrick; Gagnaire, Beatrice; Ropert, Michel. |
| In the frame of MOREST project, a common biological material, resulting of a mixture of different families produced in experimental hatchery, was reared in two different environmental fields : Normandy and Charente. Concomitantly, a pool was conditioned at the Ifremer Argenton hatchery with three different algae levels : 4%, 8% and 12% of algal dry weight per oyster dry weight. During the experiments, five immune parameters were studied in parallel with survival rate and reproductive status (stages and intensity). Site location, seasonal variations and experimental diet level clearly influenced oyster immune parameters. Haemocyte counts were higher for oysters reared in Normandy than those reared in Charente and in hatchery. Granulocyte percentage was... |
| Tipo: Text |
Palavras-chave: Defense mechanisms; Nutrition; Seasonal variations; Physiology; Crassostrea gigas; Pacific oysters. |
| Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/2003/acte-3500.pdf |
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| Caumette, P. |
| In the deepest parts of the estuarine region of Ebrie Lagoon (Abidjan Africa, (5 degree N, 4 degree W) stratified conditions have been observed during the rainy season (May to Nov.), owing to salinity differences between oxic and anoxic layers. At the interface, 3-4 m depth, phototrophic bacteria (Chromatium, Chlorobium and Pelodictyon ) developed, forming a brown layer due to their different pigments. Their production has been estimated at 41% of the total photosynthetic production during high stratification (Sep. 1981) and their biomass was used by the copepod population for 40 to 60% of its diet. During the dry season, the water column became homogeneous and oxygen was detected to 6m depth. The brown layer of phototrophic bacteria disappeared, as well... |
| Tipo: Text |
Palavras-chave: Chlorobium; Chromatium; Primary production; Photosynthesis; Estuaries; Seasonal variations; Plankton; Stratification; Vertical distribution; Bacteria; Coastal lagoons; Trophic relationships; Biomass. |
| Ano: 1984 |
URL: http://archimer.ifremer.fr/doc/1984/acte-957.pdf |
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| Registros recuperados: 87 | |
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