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| Registros recuperados: 154 | |
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| Souchu, Philippe; Gasc, Anne; Collos, Y; Vaquer, A; Tournier, Henri; Bibent, B; Deslous-paoli, Jean-marc. |
| Physical and chemical characteristics (temperature, salinity, dissolved oxygen), nutrients [dissolved inorganic nitrogen (DIN), soluble reactive phosphorus (SRP) and silicate], dissolved organic nitrogen (DON) and phosphorus and particulate matter [particulate organic carbon (POC) and nitrogen (PON) and chlorophyll a] were measured at a station located in the deepest part of the Thau lagoon (8.5 m), France, during a 10 d period of bottom anoxia in summer 1994. The upper 8 cm of sediment were also analyzed for ammonium (NH(4)(+)) and SRP concentrations in the porewater. The study period was characterized by mean wind speed under 4 m s(-1) which induced an increase of surface temperature from 18 to 29 degrees C with the formation of a thermocline. The... |
| Tipo: Text |
Palavras-chave: Anoxia; Nitrogen; Phosphorus; Eutrophication; Thau lagoon; Mediterranean Sea. |
| Ano: 1998 |
URL: http://archimer.ifremer.fr/doc/00070/18142/15694.pdf |
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| Merceron, Michel. |
| The 1998 survey of green tides on the Brittany coast was performed in the same way as that of 1997 in order to allow comparison. 11 includes an inventory ofail the concerned sites, and a precise assessment ofthirteen ofthem, the most loaded. On these ones, nitrogen fluxes were surveyed during the critical period, and the green seaweed stock on the beach and in the first waves was quantified. The climatic conditions were opposite between the two years, very dry in spring and summer 1997, and wet in 1998. The irradiance contrast was inverse, and less pronounced. The nitrate contents and mostly the flows were more important in 1998. They generated nitrogen fluxes about 3.3 times those of 1997. The total number of sites concerned in 1998 is clearly higher than... |
| Tipo: Text |
Palavras-chave: Bretagne; Nitrate; Prolifération; Ulve; Eutrophisation; Brittany; Nitrate; Proliferation; Ulva; Eutrophication. |
| Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/1999/rapport-2665.pdf |
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| Mojtahid, Meryem; Jorissen, Frans; Durrieu, Josiane; Galgani, Francois; Howa, Helene; Redois, Fabrice; Camps, Roger. |
| We present a study of benthic foraminiferal. faunas from the outer continental shelf off Congo (tropical West Africa), with the aim to determine the impact of the discharge of oily drill cuttings on the sea floor environment, to judge the regenerating capacity of the benthic ecosystem, and to investigate the possibility to develop an environmental monitoring method for open marine continental shelf environments, based on benthic foraminifera. We studied the spatial distribution and microhabitats of living and dead foraminiferal faunas, sampled in April 2003, 4 years after the end of disposal activities, in the upper 3 cm of the sediment at 9 stations (about 180 m depth) offshore Congo, that were subject to various degrees of pollution by oily cuttings from... |
| Tipo: Text |
Palavras-chave: Oily cuttings; Opportunistic taxa; Drill mud; Bio indicator; Eutrophication; Outer shelf; Benthic foraminifera. |
| Ano: 2006 |
URL: http://archimer.ifremer.fr/doc/2006/publication-2170.pdf |
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| Delgado, O; Ruiz, J; Perez, M; Romero, J; Ballesteros, E. |
| The effects of fish farming on a seagrass (Posidonia oceanica) meadow at Fornells Bay, Minorca (Balearic Islands) were studied. Changes in plant and meadow features (e.g. shoot morphology, shoot density, biomass, rhizome growth, nutrient and soluble sugars concentrations...) in three stations along a transect from a disturbed (organic pollution due to fish cultures) to an undisturbed site were assessed. The fish culture had ceased in 1991; however, seagrass decline, already reported in a previous study for the period 1988-1990, was still taking place at the time of sampling (July 1994). Differences between stations were very clear; the station closest to the fish cages showed reduced shoot density, shoot size, underground biomass, sucrose concentration and... |
| Tipo: Text |
Palavras-chave: Aquaculture; Phanérogame marine; Posidonia oceanica; Eutrophisation; Caractéristique du sédiment; Aquaculture; Seagrass; Posidonia oceanica; Eutrophication; Sediment characteristics. |
| Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/00325/43632/43250.pdf |
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| Cahet, G.; Martin, Y.. |
| An experimental eutrophication carried out with several technics on mediterranean sea water (Embiez) in autumn shows : - significant variations in the electro-chemical composition of phytoplanktonic excretion; complex organic substances are excreted during two different periods, especially after the Skeletonema costatum bloom; - close relations between heterotrophy (l4C glucose test) and excretion of organic matter by photosynthetic organisms, glucids are always predominant; - the original heterotrophy from the 14c pyruvate test; which is obviously more selective than the 14c glucose test; - the existence of different periods of active ultraplankton. |
| Tipo: Text |
Palavras-chave: Eutrophisation; Méditerranée; Embiez; Eutrophication; Mediterranean; Sea; Embiez. |
| Ano: 1979 |
URL: http://archimer.ifremer.fr/doc/00305/41670/40879.pdf |
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| Ifremer, Del; Ceva, Pleubian. |
| In 1995, the gulf of Morbihan was not showing on the whole a pronounced level of eutrophication, but has nonetheless three sites of green algae proliferation: the Auray river estuary, the branches of the Vannes and Séné estuary, as well as the outlet of the Noyalo's estuary. Only these last two sectors show algal developments that are "abnormal" and that can be linked to a specific phenomenon of eutrophication (Ulva green tide in the Rosvellec-Séné sector, Monostroma green tide in the Saint Armel-Tascon sector). In the spring of 1995, the observations made on the foreshores of the Gulf of Morbihan, excluding the islands, made it possible to estimate an algal biomass of between 2,000 and 6,000 tons. |
| Tipo: Text |
Palavras-chave: Morbihan gulf; Eutrophication; Green seaweed; Green algae; Eutrophisation; Golfe du Morbihan; Algues vertes. |
| Ano: 1996 |
URL: http://archimer.ifremer.fr/doc/1996/rapport-2085.pdf |
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| Tedetti, Marc; Bigot, Lionel; Turquet, Jean; Guigue, Catherine; Ferretto, Nicolas; Goutx, Madeleine; Cuet, Pascale. |
| We investigated the influence of freshwater discharges on biogeochemistry and benthic communities of La Saline fringing reef, the largest coral reef system of La Réunion Island (France, Indian Ocean). Sampling was conducted in February–March 2012 along a land-ocean continuum, including rivers, groundwater, reef waters, and oceanic waters. Our results indicated the discharges of basalt groundwater (enriched in nitrates) in the southern part of the reef, and the discharges of sand groundwater and river waters (enriched in organic matter) in sites located northward. These discharges mainly impacted fore reef surface waters, while groundwater resurgences were more diffuse and not clearly detected in depth. We highlighted the relationship Si(OH)4/NO3– to... |
| Tipo: Text |
Palavras-chave: Coral reefs; La Reunion; Indian Ocean; Eutrophication; Groundwater; Nutrients; Organic matter; Fluorescence. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00658/77030/78316.pdf |
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| Passy, Paul; Le Gendre, Romain; Garnier, Josette; Cugier, Philippe; Callens, Julie; Paris, Francois; Billen, Gilles; Riou, Philippe; Romero, Estela. |
| Eutrophication of the Seine estuary and the Bay of the Seine is a crucial environmental issue for the management of ecosystems and economic activities related to fisheries and tourism. A large quantity of nutrients, especially nitrogen, is brought to the coastal zone by the Seine River, the main input of that area, but also by smaller rivers along the Normandy coast. This large delivery of nitrogen leads to an imbalance between nitrogen (N), phosphorus (P) and silica (Si), which affects the growth of planktonic organisms and can exacerbate the occurrence of harmful algal blooms (HABs). These events can be damaging for shellfish fisheries, an important economic resource for the region. The study describes a new modelling chain coupling a riverine and a... |
| Tipo: Text |
Palavras-chave: Eutrophication; Harmful algal blooms; Nutrient load; Modelling; Water quality; Seine. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00300/41103/41542.pdf |
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| Le Bec, Claude; Legendre, Aurelie; Messiaen, Gregory. |
| Time series of physico-chemical data and concentrations (cell L-1) of the toxic dinoflagellate Alexandrium minutum collected in the Rance macrotidal estuary (Brittany, France) were analyzed to understand the physico-chemical processes of the estuary and their relation to changes in bloom development from 1996 to 2009. The construction of the tidal power plant in the north and the presence of a lock in the south have greatly altered hydrodynamics, blocking the zone of maximum turbidity upstream, in the narrowest part of the estuary. Alexandrium minutum occurs in the middle part of the estuary. Most physical and chemical parameters of the Rance estuary are similar to those observed elsewhere in Brittany with water temperatures between 15–18 °C, slightly... |
| Tipo: Text |
Palavras-chave: Harmful algae; Dinoflagellate; Nutrients; Eutrophication; Drainage basin; Land runoff. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00341/45257/44698.pdf |
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| Lemoine, Gérard. |
| Within the national molluscan monitoring network, a sedimentary study was carried out on five experimental sites located in southern Brittany (i.e., from Etel to Pen-Bé rivers). The study aimed to specify sediment integrating characteristics with regards to hydrobiological variables. Moreover, interactions between sediment and water column characteristics were specified. It appears that this approach is likely unappropriate to characterize interdical rearing area productivity. However, this approach can support the site evaluation on a long term basis to sustain shellfish culture management. This would require additional study to assess sediment reactivity to abnormal events like drastic salinity decrease. |
| Tipo: Text |
Palavras-chave: Sédiment; Ostréiculture; Estran; Phosphore; Eutrophisation; Sediment; Oyster culture; Intertidal area; Phosphorus; Eutrophication. |
| Ano: 1994 |
URL: http://archimer.ifremer.fr/doc/00102/21344/18967.pdf |
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| Romero, Estela; Garnier, Josette; Lassaletta, Luis; Billen, Gilles; Le Gendre, Romain; Riou, Philippe; Cugier, Philippe. |
| We provide data on nutrient export for 28 rivers in southwestern Europe and analyze long-term changes in the context of anthropogenic pressures and regulation policies. Special attention is given to seasonal variations, because the integrated annual values that are usually provided do not allow us to establish comparisons with seasonal phytoplankton dynamics. The eutrophication risk associated with river inputs is addressed by means of an indicator (Index of Coastal Eutrophication Potential, ICEP, Billen and Garnier, Mar Chem 106:148–160, 2007). An overview of the temporal evolution and the intra-annual variability of the ICEP is discussed for specific rivers and integrated coastal regions. The annual dynamics of the eutrophication indicator is analyzed to... |
| Tipo: Text |
Palavras-chave: River inputs; Coastal zone; N:P:Si stoichiometry; Eutrophication; Seasonality; Europe. |
| Ano: 2013 |
URL: http://archimer.ifremer.fr/doc/00090/20152/17928.pdf |
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| Merceron, Michel. |
| On tens of sandy beaches of Brittany, a green seaweed (Ulva) blooms during spring and summer. In the sites where the proliferation is the most important, the total biomass amounted to 20 000 t of wet weight in 1997, at the time of maximum. These "green tides" occur every year in nearly the same locations. They have a very harmful impact on local tourism. In many communes, beached and rotting algae are collected and dumped (43 000 m 3 as a whole in 1997). The main development of biomass takes place between the surf zone and the bare sand.The outbreak requires three coexisting conditions : 1) a sandy beach gently sloping, 2) a weak residual current (i.e. once the tidal back and forth movement has been filtered), 3) a nitrogen loading, even moderate (ammonium... |
| Tipo: Text |
Palavras-chave: Brittany; Eutrophication; Proliferation; Ulva; Marine algae; Bretagne; Eutrophisation; Prolifération; Ulves; Algues marines. |
| Ano: 1999 |
URL: http://archimer.ifremer.fr/doc/1999/acte-46.pdf |
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| Lemonnier, Hugues; Lantoine, Francois; Courties, Claude; Guillebault, Delphine; Nezan, Elisabeth; Chomerat, Nicolas; Escoubeyrou, Karine; Galinie, Christian; Blockmans, Bernard; Laugier, Thierry. |
| Tropical shrimp aquaculture systems in New Caledonia regularly face major crises resulting from outbreaks of Vibrio infections. Ponds are highly dynamic and challenging environments and display a wide range of trophic conditions. In farms affected by vibriosis, phytoplankton biomass and composition are highly variable. These conditions may promote the development of harmful algae increasing shrimp susceptibility to bacterial infections. Phytoplankton compartment before and during mortality outbreaks was monitored at a shrimp farm that has been regularly and highly impacted by these diseases. Combining information from flow cytometry, microscopy, pigment and phylogenetic analysis, the presence of Picocyanobacteria, Prasinophyceae and Diatomophyceae were... |
| Tipo: Text |
Palavras-chave: Tropical aquaculture pond; Litopenaeus stylirostris; Vibriosis; Eutrophication; Phytoplankton; Harmful algae. |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00343/45411/44986.pdf |
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| Registros recuperados: 154 | |
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