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Registros recuperados: 114 | |
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Pasquet, Virginie; Cherouvrier, Jean-rene; Farhat, Firas; Thiery, Valerie; Piot, Jean-marie; Berard, Jean-baptiste; Kaas, Raymond; Serive, Benoit; Patrice, Thierry; Cadoret, Jean-paul; Picot, Laurent. |
The performance of microwaves irradiation (MAE and VMAE) to extract pigments from two marine microalgae was compared to conventional processes (cold and hot soaking and ultrasound-assisted extraction). Pigments were quantified by RP-HPLC and extraction performance was assessed regarding rapidity, reproducibility and extraction yields. Scanning electron microscopy was used at all extraction steps to assess the impact of the process on microalgal cell integrity. Freeze-drying and pigments extraction preserved microalgae cell integrity (except sonication) and evoked agglutination in superposed cells layers. All processes performed on Dunaliella tertiolecta (chlorophyte) lead to rapid pigments extraction, and equivalent pigments extraction yields, the absence... |
Tipo: Text |
Palavras-chave: Pigments; Microalgae; Microwave; Extraction; Chlorophyll; Fucoxanthin; Carotene; MAE; VMAE. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00029/14059/11533.pdf |
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Lapucci, Chiara; Rella, Marina Ampolo; Brandini, Carlo; Ganzin, Nicolas; Gozzini, Bernardo; Maselli, Fabio; Massi, Luca; Nuccio, Caterina; Ortolani, Alberto; Trees, Charles. |
The estimation of chlorophyll concentration in marine waters is fundamental for a number of scientific and practical purposes. Standard ocean color algorithms applicable to moderate resolution imaging spectroradiometer (MODIS) imagery, such as OC3M and MedOC3, are known to overestimate chlorophyll concentration ([CHL]) in Mediterranean oligotrophic waters. The performances of these algorithms are currently evaluated together with two relatively new algorithms, OC5 and SAM_LT, which make use of more of the spectral information of MODIS data. This evaluation exercise has been carried out using in situ data collected in the North Tyrrhenian and Ligurian Seas during three recent oceanographic campaigns. The four algorithms perform differently in Case 1 and... |
Tipo: Text |
Palavras-chave: Chlorophyll; Algorithm; Moderate resolution imaging spectroradiometer; Tyrrhenian Sea; Ligurian Sea. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00109/21991/19795.pdf |
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Agusti, Susana; Martinez-ayala, Juan; Regaudie-de-gioux, Aurore; Duarte, Carlos M.. |
Increased oligotrophication is expected for oligotrophic areas as a consequence of ocean warming, which reduces diffusive vertical nutrient supply due to strengthened stratification. Evidence of ocean oligotrophication has been, thus far, reported for the open ocean. Here we reported oligotrophication and associated changes in plankton community metabolism with warming in a pristine, oligotrophic Mediterranean coastal area (Cap Salines, Mallorca Island, Spain) during a 10 years time series. As a temperate area, there were seasonal patterns associated to changes in the broad temperature range (12.0.28.4.C), with a primary phytoplankton bloom in late winter and a secondary one in the fall. Community respiration (R) rates peaked during summers and showed... |
Tipo: Text |
Palavras-chave: Oligotrophiocation; Mediterranean sea; Respiration; Net community production; Nutrients; Gross primary production; Warming; Chlorophyll. |
Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00419/53091/54048.pdf |
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Aminot, Alain; Guillaud, Jean-francois; Kerouel, Roger. |
The data of hydrology, nutrients and chlorophyll obtained in the Bay of Seine over the period 1978-1994, from 14 océanographie cruises, are synthetised and illustrated by an atlas. The Bay is a typical example of a coastal area influenced by a large river. In winter, the nutrient input is drained off into the eastern Channel. In spring, nutrients are consumed intensively. Silicate is the first that drops to limiting levels. The spring bloom generally begins in the centre-east of the Bay. Chlorophyll a can reach up to 40-70 µg/l during the year, values typical of eutrophic coastal areas. Despite the regular increase of nitrogen inputs, the biomass (as chlorophyll) has not significantly changed over a fifteen year period. |
Tipo: Text |
Palavras-chave: Chlorophyll; Nutrients; Hydrology; Bay of Seine; Chlorophylle; Nutriments; Hydrologie; Baie de Seine. |
Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/1997/rapport-1428.pdf |
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Huret, Martin; Dadou, Isabelle; Dumas, Franck; Lazure, Pascal; Garcon, Véronique. |
A coupled three-dimensional physical-biogeochemical model was developed in order to simulate the ecological functioning of the Rio de la Plata estuary and plume. The biogeochemical model reproduces the nitrogen cycle between five compartments: dissolved inorganic nitrogen, phytoplankton, zooplankton, detritus and dissolved organic nitrogen. The coupling is tested in seasonal climatological configurations and for the particular year 1999. The circulation is forced with Parana and Uruguay rivers discharges, NCEP wind and tide. The biogeochemical model includes loads of inorganic and organic nitrogen from both rivers. The model reproduces the correct tidal amplitudes in the estuary, as well as the most outstanding features of the observed horizontal and... |
Tipo: Text |
Palavras-chave: Rio de la Plata; SeaWiFS; Primary production; Chlorophyll; River plumes; Biogeochemical modelling; Physical. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-334.pdf |
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Gohin, Francis; Saulquin, Bertrand; Oger-jeanneret, Helene; Lozac' H, L; Lampert, Luis; Lefebvre, Alain; Riou, Philippe; Bruchon, F. |
The application of the new Water Framework Directive (WFD) of the European Union will require a dense and frequent monitoring of chlorophyll-a near the coast. Not counting the transitional water bodies located in the vicinity of estuaries, not less than seventy four coastal water bodies have to be monitored along the coast of the French Atlantic continental shelf and the English Channel. All the available data have to be gathered to implement a comprehensive monitoring scheme. To this purpose, we evaluate the capacity of ocean colour imagery to complete the conventional in situ data set collected in coastal networks. Satellite-derived chlorophyll-a concentration is obtained by the application of a coastal Look-Up-Table to water-leaving radiance of the... |
Tipo: Text |
Palavras-chave: SeaWiFS; Coastal; Surveillance; Monitoring; Chlorophyll; Satellite. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4501.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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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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Gohin, Francis; Loyer, S; Lunven, Michel; Labry, Claire; Froidefond, J; Delmas, Daniel; Huret, Martin; Herbland, Alain. |
In biological modelling of the coastal phytoplankton dynamics, the light attenuation coefficient is often expressed as a function of the concentrations of chlorophyll and mineral suspended particulate matter (SPM). In order to estimate the relationship between these parameters over the continental shelf of the northern Bay of Biscay, a set of in situ data has been gathered for the period 1998-2003 when SeaWiFS imagery is available. These data comprise surface measurements of the concentrations of total SPM, chlorophyll, and irradiance profiles from which is derived the attenuation coefficient of the photosynthetically available radiation, K-PAR. The performance of the IFREMER look-up table used to retrieve the chlorophyll concentration from the SeaWiFS... |
Tipo: Text |
Palavras-chave: Bay of Biscay; SeaWiFS; Sediment; Chlorophyll; Ocean color. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-1172.pdf |
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Kilic, Ece; Akpinar, Anil; Yucel, Nebil. |
Rivers are primary receiving environments for agricultural runoff and for domestic and industrial discharges. Rivers assimilate and treat incoming pollution load until self-purification capacity is reached. The remaining pollution load and natural nutrients are carried to and discharged into the sea causing variations in the receiving area's nutrient concentration. This study evaluated nutrient loads and effects of the Asi River on the northeastern Mediterranean Sea. Monitoring data from 2006 to 2014 from the State of Hydraulic Works of Turkey were analyzed with an interpolation-based average-estimator model for nutrient load calculation. The nutrient load's impact on the receiving area was determined using satellite images. Annual nitrite (NO2), nitrate... |
Tipo: Text |
Palavras-chave: Orontes River; Riverine input; Chlorophyll; Iskenderun Bay; Eastern Mediterranean. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00473/58518/61037.pdf |
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Menesguen, Alain; Gohin, Francis. |
Accumulation of heat, or dissolved substances (nutrients, pollutants, etc.), or fine suspended particles in a water body is a key process in the functioning of aquatic ecosystems and their resistance to perturbations. In complex and wide open environments such as marine ecosystems, net accumulation is not only linked to the local renewal capacity of the water body, but also to the partial recirculation of water due to convective cells of various sizes. The English Channel, which can be considered as mainly dominated by tidal movements, exhibits such a complex quasi-permanent long-term circulation, made of a central "river" bordered with a lot of nested gyres. Here, we show that structures visible on satellite images of SST (Sea Surface Temperature),... |
Tipo: Text |
Palavras-chave: Remote sensing; Suspended Particulate Matter; Chlorophyll; SST; Retention structures; Tidal residual circulation; Steady state model; English Channel. |
Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2181.pdf |
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Aminot, Alain; Kerouel, Roger. |
During the cruises "SUROIT 1", "SUROIT 3" and "THALIA 1", many analyses of dissolved oxygen and chlorophyll have been carried out in order to ascertain some effects of oil spill of "AMOCO CADIZ" on oxygen concentrations and phytoplancton behaviour. These first results show an under-saturation of oxygen, four weeks after stranding, in sea-water standing between 10 to 20 milles eastward of "AMOCO CADIZ". These data allow to do some considerations about oxydation of hydrocarbons in sea-water. In estuaries, especially Aber Wrac'h, one of the most polluted, the analyses do not show obvious anomaly one month after oil spill. Quantitative results on chlorophyll "a" and phaeopigments don't seem to show any noticeable disturbance, neither off, nor near the coast,... |
Tipo: Text |
Palavras-chave: Amoco Cadiz; Chlorophylle; Oxygène dissous; Manche; Amoco Cadiz; Chlorophyll; Dissolved oxygen; Engllsh Channel. |
Ano: 1978 |
URL: http://archimer.ifremer.fr/doc/00306/41719/40930.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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Le Moullac, Gilles; Tiapari, Jerome; Teissier, Hinano; Martinez, Elodie; Cochard, Jean-claude. |
The growth and reproductive cycle of cultured black-lipped pearl oysters, Pinctada margaritifera (L.), were studied in the Gambier Islands (134°52' W, 23°07' S) from September 2002 to August 2003. Temperatures were recorded throughout the year, revealing seasonal temperature variations between 22.3 °C and 27.8 °C. The mean annual chlorophyll a value, as computed from satellite data, was 0.188 ± 0.075 µg L-1. To study growth and reproduction, 720 two-year-old individuals were ear hung on longlines suspended at a depth of 7 m. Samples were taken twice a month to obtain the following measurements: shell height; wet weight of flesh and total oyster; dry weight of adductor muscle, mantle and visceral mass; and glycogen content. Gonad development was also... |
Tipo: Text |
Palavras-chave: Pearl oyster; Pinctada margaritifera; Growth; Reproduction; Temperature; Chlorophyll; Seasonality; Gambier archipelago. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00040/15099/13570.pdf |
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Registros recuperados: 114 | |
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