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| Registros recuperados: 51 | |
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| Martinez, Carlos; Mairet, Francis; Bernard, Olivier. |
| Microalgae can be cultivated in closed or open photobioreactors (PBR). In these systems, light rapidly decreases as it passes through the culture due to the turbidity of the medium. Thus, microalgae experiment different light intensities depending on their position in the medium. In this paper, we study theoretically how the growth rate of microalgae is affected by different factors; incident light intensity, form of the PBR, microalgae population density, turbidity of non-microalgae components, and light path-length of the reactor. We show that for different types of PBR the average growth rate is completely determined by the incident light intensity and the optical depth. In the case of vertical cylindrical PBRs illuminated from above (e.g. race-way or... |
| Tipo: Text |
Palavras-chave: Photobioreactor; Optical depth; Photoinhibition; Light limitation; Turbidity; Modelling. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00450/56133/57675.pdf |
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| Zaragosi, Sébastien; Bourillet, Jean-francois; Eynaud, Frédérique; Toucanne, Samuel; Denhard, Benjamin; Van Toer, Aurélie; Lanfumey, Valentine. |
| The compilation of results obtained on three giant piston cores from the Whittard, Shamrock and Guilcher turbidite levees reveals a high-resolution stratigraphic record for the Bay of Biscay. Due to the abundance of reworked sediments in these sedimentary environments, a specific methodological approach, based on an X-ray-assisted subsampling phase associated with sedimentological, geochemical and micropalaeontological analyses, was implemented. With an accurate chronological framework, this multi-proxy investigation provides observations on the 'Fleuve Manche' palaeoriver and the British-Irish Ice Sheet (BIS) histories over the last 20,000 years. The results obtained highlight the direct influence of the decay of the BIS on the Bay of Biscay deep-sea... |
| Tipo: Text |
Palavras-chave: Sedimentation; Glaciation; Turbidity; Deep sea; Bay of Biscay; French Atlantic margin. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2142.pdf |
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| Lefebvre, Alain; Devreker, David. |
| The first quantitative and comprehensive assessment of the eutrophication status from coastal to offshore French waters was performed within the Marine Strategy Framework Directive (MSFD descriptor 5) for the English Channel, the southern bight of the North Sea, the Celtic Seas, the Bay of Biscay and the Western Mediterranean Sea. Based on a combination of different data sources (in situ, satellite, and modeling products), a fully-integrated dataset was generated over the period 2010–2016. Using the best available knowledge on the eutrophication process and definition, the assessment procedure was implemented considering nutrient pressures, and direct and indirect effects of excessive inputs. The different steps of the assessment were: (i) Establishment of... |
| Tipo: Text |
Palavras-chave: Eutrophication; Assessment; Marine Strategy Framework Directive (MSFD); Water Framework Directive (WFD); Oslo and Paris Convention (OSPAR); English Channel; Celtic Seas; Bay of Biscay; Mediterranean Sea; Nutrients; Chlorophyll; Oxygen; Turbidity; Phytoplankton; Macro-algae. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00641/75350/76083.pdf |
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| Ouillon, S.; Douillet, Pascal; Lefebvre, J. P.; Le Gendre, Romain; Jouon, Aymeric; Bonneton, P.; Fernandez,; Chevillon, C.; Magand, O.; Lefevre, J.; Le Hir, Pierre; Laganier, R.; Dumas, Franck; Marchesiello, P.; Madani, A. Bel; Andrefouet, S.; Panche, J. Y.; Fichez, R.. |
| The south-west lagoon of New Caledonia is a wide semi-open coral reef lagoon bounded by an intertidal barrier reef and bisected by numerous deep inlets. This paper synthesizes findings from the 2000-2008 French National Program EC2CO-PNEC relative to the circulation and the transport of suspended particles in this lagoon. Numerical model development (hydrodynamic, fine suspended sediment transport, wind-wave, small-scale atmospheric circulation) allowed the determination of circulation patterns in the lagoon and the charting of residence time, the later of which has been recently used in a series of ecological studies. Topical studies based on field measurements permitted the parameterisation of wave set-up induced by the swell breaking on the reef barrier... |
| Tipo: Text |
Palavras-chave: Hydrodynamics; Suspended sediment; New Caledonia; Coral reef lagoon; Sediment; Turbidity; Resuspension. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00014/12526/9401.pdf |
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| Gohin, Francis; Bryère, Philippe; Lefebvre, Alain; Sauriau, Pierre-guy; Savoye, Nicolas; Vantrepotte, Vincent; Bozec, Yann; Cariou, Thibault; Conan, Pascal; Coudray, Sylvain; Courtay, Gaelle; Françoise, Sylvaine; Goffart, Anne; Hernández Fariñas, Tania; Lemoine, Maud; Piraud, Aude; Raimbault, Patrick; Rétho, Michael. |
| The consistency of satellite and in situ time series of Chlorophyll-a (Chl-a), Turbidity and Total Suspended Matters (TSM) was investigated at 17 coastal stations throughout the year 2017. These stations covered different water types, from relatively clear waters in the Mediterranean Sea to moderately turbid regions in the Bay of Biscay and the southern bight of the North-Sea. Satellite retrievals were derived from MODIS/AQUA, VIIRS/NPP and OLCI-A/Sentinel-3 spectral reflectance. In situ data were obtained from the coastal phytoplankton networks SOMLIT (CNRS), REPHY (Ifremer) and associated networks. Satellite and in situ retrievals of the year 2017 were compared to the historical seasonal cycles and percentiles, 10 and 90, observed in situ. Regarding the... |
| Tipo: Text |
Palavras-chave: Satellite; Coastal monitoring; Chlorophyll-a; Total suspended matter; Turbidity. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00645/75669/76536.pdf |
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| Droz, Laurence; Dos Reis, A. T.; Rabineau, Marina; Berne, Serge; Bellaiche, G. |
| The Balearic Basin is a young basin composed of thick Plio-Quaternary sediments, including active gravity sedimentation. During the Quaternary, gravity processes deposited (1) turbidite systems, either as symmetrical fans (Petit-Rhone and Valencia fans) or asymmetrical ridges (Marseille-Planier, Grand- Rhone and Pyreneo-Languedocian ridges) and (2) several mass-transport deposits, indicating recurrent sedimentary failures of the margin. This paper synthesizes previous works and proposes a chronological sedimentary evolution for the basin. Except for the last 20 ka, the chronostratigraphy remains poorly constrained but should soon be established for the last 500 ka, based on the PROMESS1 drillings on the outer shelf of the Gulf of Lions, and hopefully for... |
| Tipo: Text |
Palavras-chave: Gulf of Lion; Quaternary evolution; Turbidity; Sedimentary system. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2171.pdf |
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| Charpentier, Aude; Grillas, P; Lescuyer, F; Coulet, E; Auby, Isabelle. |
| The consequences of a sudden decrease in water salinity on a macrophyte community dominated by the marine species Zostera noltii were investigated in a shallow coastal lagoon (Southern France). The expected change in the community assemblage was a competitive displacement of Z. noltii by Potamogeton pectinatus and Ruppia cirrhosa. However, the results of an eight-year survey did not validate this hypothesis. Zostera noltii remained dominant after three years at low salinity (ca. 5) and then suddenly disappeared within one year. The decline of Z. noltii was not associated with an increase of other species. The maximum depth colonized by all species decreased, suggesting that light availability became a limiting factor for the aquatic vegetation. The high... |
| Tipo: Text |
Palavras-chave: Mediterranean sea; Lagoon; Recovery; Loss; Turbidity; Salinity; Mapping; Seagrass. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-3693.pdf |
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| Ouillon, Sylvain; Douillet, Pascal; Petrenko, Anne; Neveux, Jacques; Dupouy, Cecile; Froidefond, Jean-marie; Andrefouet, Serge; Munoz-caravaca, Alain. |
| Is it possible to derive accurately Total Suspended Matter concentration or its proxy, turbidity, from remote sensing data in tropical coastal lagoon waters? To investigate this question, hyperspectral remote sensing reflectance, turbidity and chlorophyll pigment concentration were measured in three coral reef lagoons. The three sites enabled us to get data over very diverse environments: oligotrophic and sediment-poor waters in the southwest lagoon of New Caledonia, eutrophic waters in the Cienfuegos Bay (Cuba), and sediment-rich waters in the Laucala Bay (Fiji). In this paper, optical algorithms for turbidity are presented per site based on 113 stations in New Caledonia, 24 stations in Cuba and 56 stations in Fiji. Empirical algorithms are tested at... |
| Tipo: Text |
Palavras-chave: Ocean color; Remote sensing; Sediment transport; Suspended matter; Turbidity; New Caledonia; Cuba; Fiji. |
| Ano: 2008 |
URL: https://archimer.ifremer.fr/doc/00203/31417/29808.pdf |
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| 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 |
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| Dutertre, Mickael; Beninger, Peter G.; Barille, Laurent; Papin, Mathias; Haure, Joel. |
| The recent appearance and invasion of feral oysters (Crassostrea gigas) along the northern European Atlantic coast, underscores the necessity to investigate the relationship between environmental variables, reproductive physiology, larval development and recruitment. We studied these relationships at both high (HT) and intermediate (IT) - turbidity sites, through historical data on water temperatures, multi-parameter environmental probes, histological analyses, and field collections of planktonic larvae and settled post-larvae in 2005 and 2006. A progressive warming trend was observed, especially since 1995, when oyster proliferation first became severe. Threshold temperatures for oocyte growth, larval development and settlement were achieved in both 2005... |
| Tipo: Text |
Palavras-chave: Aquaculture; Climate warming; Coastal waters; Crassostrea gigas; Reproductive cycle; Oyster larvae; Settlement; Turbidity. |
| Ano: 2010 |
URL: http://archimer.ifremer.fr/doc/00000/11150/7938.pdf |
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| Dutertre, Mickael; Beninger, Peter G.; Barille, Laurent; Papin, Mathias; Rosa, Philippe; Barille, Anne-laure; Haure, Joel. |
| The proliferation of the voluntarily-introduced cupped oyster, Crassostrea gigas, has attained the proportions of species invasion in many intertidal habitats in Europe, presumably resulting from successful reproduction of farmed individuals. It is thus imperative to better understand the reproductive characteristics of farmed oysters, since they are directly under human control. We quantified the dry tissue mass (DTM), gametosomatic index (GSI), and reproductive cycle of farmed oysters at two sites in Bourgneuf Bay, France, in relation to environmental parameters using continuously-recording probes in 2005 and 2006. The GSI was developed for this study, based on the actual area occupied by gametes, rather than the area of the gonad previously used for... |
| Tipo: Text |
Palavras-chave: Atlantic Ocean; Crassostrea gigas; Oyster farming; Bivalve; Gametosomatic index; Biological invasion; Atresia; Oocytes; Turbidity; Temperature; Reproduction. |
| Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6871.pdf |
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| Struski, Caroline; Bacher, Cedric. |
| The macrotidal bay of Marennes-Oléron is the most important French site for shellfish production (oysters and mussels); yet the primary productivity of the phytoplankton compartment in this system is not well known. In this study, photosynthetic parameters were determined using 14C incubations of bottom and surface water samples, during fall, winter and summer (2001¿2002), along a north¿south transect in the bay. Estimates of primary productivity showed that water column primary production is light-limited in the bay and that a BZpI0 type model can be applied. Spatial differences existed in the bay, with a more productive northern zone and less productive river area. With a water column primary production of 185 g C m−2 yr−1,... |
| Tipo: Text |
Palavras-chave: BZpI0 model; Tidal bay; Light limitation; Turbidity; Phytoplankton; Photosynthesis parameters. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-572.pdf |
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| Souza,Carine de F.; Pereira Junior,Waterloo; Garcia,Luciano de O.; Santos,Felipe C. dos; Baldisserotto,Bernardo. |
| ABSTRACT This study analyzed the relationship between several water quality parameters (pH, hardness, alkalinity, turbidity, iron and manganese) levels measured over a 16 year period with fish distribution and aquaculture in the state of Rio Grande do Sul, Southern Brazil. The mean pH values were within a neutral range (6.5-7.5), but the maximum and minimum values reached inappropriate levels for fish farming in some cities. Alkalinity levels were very low (except in the southwest region of the state), which may have contributed to pH variation. Hardness, turbidity, iron (except the region near Caçapava do Sul City) and manganese were within safe ranges for fish farming; however, turbidity levels occasionally increased to levels outside the safe range. In... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Alkalinity; Hardness; Iron; PH; Turbidity. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252016000300205 |
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| Registros recuperados: 51 | |
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