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| Registros recuperados: 369 | |
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| Lok, Aynur; Metin, Gulnur; Acarli, Sefa; Goulletquer, Philippe. |
| Considering the filtration capacity of mussels to qualitative particle selection, our study focused directly on ingested species by assessing mussel stomach content of various size classes (1-5 cm) over a year (August 97-June 98) rather than monitoring seawater samples. Different size of mussels (1, 2, 3, 4, 5 cm in length) was sampled monthly from the sides of fish cage floats in Urla-Izmir. Stomach contents were analyzed under microscope and different plankton species were grouped taxonomically. Bacillariophycea, Dinophyceae, Oxyphceae, Euglenophyceae as phytoplanktonic species were observed in the stomach contents of mussels as well as zooplanktonic species including Ciliata, Cladocera, Copepod, bivalve and gastropod larvae. Over the sampling period,... |
| Tipo: Text |
Palavras-chave: Mussel; Mytilus galloprovincialis; Harmful; Phytoplankton; Stomach content; Aegean Sea. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00032/14329/11621.pdf |
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| Gohin, Francis; Lampert, Luis; Guillaud, Jean-francois; Herbland, Alain; Nezan, Elisabeth. |
| A phytoplankton bloom was observed in late winter 2000, on the continental shelf offshore of southern Brittany, in northwestern Bay of Biscay. This bloom appeared initially along the 120-m isobath, in stratified and clear waters, at the interface between the oceanic water and the plumes of southern Brittany rivers (mainly the Loire and Vilaine). The development of the bloom was triggered by favourable meteorological conditions, characterised by solar irradiance reaching the maximum level expected for that period of the year. Outside of the bloom area, the phytoplankton photosynthesis was irradiance limited: inshore, because of the stronger attenuation of the light; offshore, because of the weak stratification. The hydrological conditions at the onset of... |
| Tipo: Text |
Palavras-chave: Bay of Biscay; Coscinodiscus; Algal bloom; Phytoplankton; Ocean colour; Satellite sensing. |
| Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/2003/publication-463.pdf |
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| Lopez-joven, Maria-carmen; Rolland, Jean-luc; Haffner, Philippe; Caro, Audrey; Roques, Cecile; Carre, Claire; Travers, Marie-agnes; Abadie, Eric; Laabir, Mohamed; Bonnet, Delphine; Destoumieux-garzon, Delphine. |
| Vibrio species have been associated with recurrent mass mortalities of juvenile oysters Crassostrea gigas threatening oyster farming worldwide. However, knowledge of the ecology of pathogens in affected oyster farming areas remains scarce. Specifically, there are no data regarding (i) the environmental reservoirs of Vibrio populations pathogenic to oysters, (ii) the environmental factors favoring their transmission, and (iii) the influence of oyster farming on the persistence of those pathogens. This knowledge gap limits our capacity to predict and mitigate disease occurrence. To address these issues, we monitored Vibrio species potentially pathogenic to C. gigas in 2013 and 2014 in the Thau Lagoon, a major oyster farming region in the coastal French... |
| Tipo: Text |
Palavras-chave: Vibrio; Shellfish farming; Bivalve mollusks; Mortality outbreak; Phytoplankton; Zooplankton. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00463/57479/59598.pdf |
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| Bougaran, Gael; Bernard, Olivier; Sciandra, Antoine. |
| It is well documented that the combination of low nitrogen and phosphorus resources can lead to situations where colimitation of phytoplankton growth arises, yet the underlying mechanisms are not fully understood. Here, we propose a Droop-based model built on the idea that colimitation by nitrogen and phosphorus arises from the uptake of nitrogen. Indeed, since N-porters are active systems, they require energy that could be related to the phosphorus status of the cell. Therefore, we assumed that N uptake is enhanced by the P quota. Our model also accounts for the biological observations that uptake of a nutrient can be down-regulated by its own internal quota, and succeeds in describing the strong contrast for the non-limiting quotas under N-limited and... |
| Tipo: Text |
Palavras-chave: Colimitation; Phytoplankton; Mathematical model; Quota. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00011/12216/9060.pdf |
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| Jacques, G.; De Billy, G.. |
| One approach to the problem of aquaculture consists in a simple acceleration of natural processes in extended areas of salt or brackish water. From this point of view, the authors have been interested in the effect of moderate fertilization on natural communities . A first series of experiments (8) was made in an external tank of 3000 liters. After fertilization, the development of flowering diatoms was obtained each time. The time of latency, the level of production reached, the composition of the final communities is to some extent variable, but bacterial development may be neglected. In contrast to earlier results, obtained in small volumes of water, these experiments have always led to simplified communities mostly dominated by the diatom... |
| Tipo: Text |
Palavras-chave: Phytoplancton; Fertilisation; Chémostat.; Phytoplankton; Nutrient; Enrichment; Chemostat. |
| Ano: 1979 |
URL: http://archimer.ifremer.fr/doc/00306/41688/40897.pdf |
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| Mairet, Francis; Baron, Regis. |
| The Droop model allows to represent microalgae growth limited by a nutrient, using a cell quota (also referred to as variable-yield) approach. Single-cell measurements have revealed quota heterogeneity in phytoplankton collected from field studies. Such heterogeneity can be due, among other factors, to spatial structure (e.g. in biogeochemical cycles in the ocean, or for photobioreactors connected in series). Nonetheless, quota heterogeneity is generally omitted in modelling studies, using an average quota approach, or included in size-structured or individual-based models. Here, we propose a distributed Droop equation to tackle this problem, considering subpopulation growth -in line with Droop macroscopic view- rather than cell division dynamics. We... |
| Tipo: Text |
Palavras-chave: Population Balance Model; Variable-yield model; Cell Quota; Phytoplankton; Microalgae. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00600/71187/69542.pdf |
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| Nival, Paul; Malara, G.. |
| Choosing the best conditions for the cultivation of plankton in tanks is a difficult deal, which is generally solved by means of subjective estimations. A better way of looking for these conditions is the use of a mathematical model. _ We have tried to built a model that accounts for the physical and biological characteristics of the tanks. The data concerning the physiological characteristics of the different group of organisms encountered are too scarce to allow all of them to be taken into account. The system studied here is composed of nutrients, phytoplankton, herbivorous copepods and rotifers to which benthic algae have been added. With the hypothesis of 3 elements (phyto - zooplankton - nutrients) it can be showed that when an equilibrium is... |
| Tipo: Text |
Palavras-chave: Phytoplancton; Zooplancton; Culture; Modèle mathématique; Phytoplankton; Zooplankton; Culture; Mathematical model. |
| Ano: 1979 |
URL: http://archimer.ifremer.fr/doc/00306/41673/40882.pdf |
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| Labry, Claire; Delmas, Daniel; Herbland, Alain. |
| Previous studies conducted on the continental shelf in the Southeast Bay of Biscay influenced by Gironde waters (one of the two largest rivers on the French Atlantic coast) showed the occurrence of late winter phytoplankton blooms and phosphorus limitation of algal growth thereafter. In this context, the importance of dissolved organic phosphorus (DOP) for both algae and bacteria was investigated in 1998 and 1999 in terms of stocks and fluxes. Within the mixed layer, although phosphate decreased until exhaustion from winter to spring, DOP remained high and phosphate monoesters made up between I I to 65% of this pool. Total alkaline phosphatase activity (APA, V-max) rose gradually from winter (2-8 nM h(-1)) to late spring (100-400 nM h-1), which was mainly... |
| Tipo: Text |
Palavras-chave: Phytoplankton; Phosphate; Gironde; DOP; Bacteria; Alkaline phosphatases. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-608.pdf |
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| Videau, Christiane; Ryckaert, Mireille; L' Helguen, Stéphane. |
| Phytoplankton distribution and primary productivity were investigated in the Bay of Seine (eastern English Channel, France) in spring and early summer of 1992 and 1994. In 1992, the horizontal distribution of phytoplankton species was determined over the whole Bay of Seine. In 1994, species distribution and primary productivity were studied along the salinity gradient of the Seine plume and in the neighbouring marine waters. Phytoplankton distribution was characterised by the permanent diatom dominance from early spring to early summer. The spring bloom did not occur uniformly over the bay, but was initiated in the marine waters, in the middle of the bay and progressed towards the coast where it developed, in June, in the diluted waters of the Seine plume.... |
| Tipo: Text |
Palavras-chave: Baie de Seine; Production primaire; Phytoplancton; Bay of Seine; Primary productivity; Phytoplankton. |
| Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00333/44398/44057.pdf |
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| Neveux, Jacques; Lefebvre, Jean-pierre; Le Gendre, Romain; Dupouy, Cecile; Gallois, Francis; Courties, Claude; Gerard, Philippe; Fernandez, Jean-michel; Ouillon, Sylvain. |
| During the Echolag cruise (13 February-8 March 2007), the effect of 16-30 knot trade winds on abundance, community structure and dynamics of phytoplankton was investigated in the southern part of the New Caledonian coral reefs and surrounding oceanic waters. In this area, the coral reefs form two horn-like structures (hereinafter referred to as 'horn reefs'), oriented south-east, and separated by a relatively deep valley. Three repeated samplings at one week intervals of a 32 station array showed that trade winds induce surface water cooling and significant enrichment of mid- and bottom waters above the reef shelf. This enrichment appeared as the result of a general rise of the oceanic thermocline and nitracline due to the combination of trade winds and... |
| Tipo: Text |
Palavras-chave: Chlorophyll; Phycoerythrin; Flow cytometry; Phytoplankton; In vivo fluorescence; Growth rate; Trade winds; Lagoon; Internal wave; New Caledonia. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00013/12437/9258.pdf |
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| Belin, Catherine. |
| Different ways are explored for presenting 12 years of data on phytoplankton species and toxins in shellfish collected along the French coast and within the framework of the French Phytoplankton Monitoring Network. The advantages and difficulties of aggregating data in different dimensions are discussed. For example, graphs appear suitable only for restricted areas, while mapping is necessary for results on regional or larger scales. Within each of these broad categories, considerable care is required when identifying the appropriate type of information and presentation. |
| Tipo: Text |
Palavras-chave: Data presentation; Mapping; Monitoring; Phytoplankton; Plotting. |
| Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00446/55775/57627.pdf |
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| Perruche, Coralie; Riviere, Pascal; Pondaven, Philippe; Carton, Xavier. |
| This paper aims at studying analytically the functioning of a very simple ecosystem model with two phytoplankton species. First, using the dynamical system theory, we determine its nonlinear equilibria, their stability and characteristic timescales with a focus on phytoplankton competition. Particular attention is paid to the model sensitivity to parameter change. Then, the influence of vertical mixing and sinking of detritus on the vertically-distributed ecosystem model is investigated. The analytical results reveal a high diversity of ecosystem structures with fixed points and limit cycles that are mainly sensitive to variations of light intensity and total amount of nitrogen matter. The sensitivity to other parameters such as remineralisation, growth... |
| Tipo: Text |
Palavras-chave: Water mixing; Dynamical system; Phytoplankton; Competition; Ecosystem; Modelling. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/2009/publication-7334.pdf |
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| Morel, A.; Claustre, H.; Antoine, D.; Gentili, B.. |
| The optical properties of Case 1 waters have been empirically related to the chlorophyll concentration, [Chl], historically used as an index of the trophic state and of the abundance of the biological materials. The well-known natural variability around the mean statistical relationships is here examined by comparing the apparent optical properties (spectral downward irradiance attenuation and reflectance) as a function of [Chl] in two Case 1 environments, the Pacific and Mediterranean waters. These oceanic zones apparently represent two extremes of the possible bio-optical variability range around the mean. The systematic deviations, in both directions with respect to the average laws, mainly result from the differing contents in non-algal detrital... |
| Tipo: Text |
Palavras-chave: Light absorption; Algal biomass; Ocean color; Chlorophyll; Sea; Phytoplankton; Model; Coefficients; Algorithms. |
| Ano: 2007 |
URL: https://archimer.ifremer.fr/doc/00209/32012/30549.pdf |
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| Percopo, Isabella; Siano, Raffaele; Cerino, Federica; Sarno, Diana; Zingone, Adriana. |
| The section of the Liguro-Provencal basin north of the Balearic Islands is one of the most productive sites in the whole Mediterranean Sea, with intense phytoplankton bloom lasting about 2 months in late winter-early spring. The phytoplankton species composition of the area was investigated using light and electron microscopy to analyze bottle and net samples collected at several stations in spring 2000 and 2003. Serial dilution cultures established from bottle samples were also examined. A total of 168 phytoplankton taxa was identified, consisting of 73 Coscinodiscophyceae, 47 Dinophyceae, 25 Coccolithophyceae and 4 Prymnesiophyceae, 5 Prasinophyceae, 3 Chrysophyceae, 2 Cryptophyceae, 2 Dictyochophyceae, 1 Euglenophyceae, 1 Pelagophyceae, 1... |
| Tipo: Text |
Palavras-chave: Check-list; Diversity; NW Mediterranean Sea; Phytoplankton; Serial dilution cultures. |
| Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00038/14916/12245.pdf |
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| Registros recuperados: 369 | |
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