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Registros recuperados: 238 | |
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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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Giorgetti, Alessandra; Lipizer, Marina; Molina Jack, Maria Eugenia; Holdsworth, Neil; Jensen, Hans Mose; Buga, Luminita; Sarbu, George; Iona, Athanasia; Gatti, Julie; Larsen, Martin; Fyrberg, Lotta; Østrem, Ann Kristin; Schlitzer, Reiner. |
Tipo: Text |
Palavras-chave: Nutrients; Oxygen; Acidity; Contaminants; Sediment; Biota; Aggregated datasets. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00663/77519/79314.pdf |
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Sauzede, Raphaelle; Claustre, Hervé; Bittig, Henry; Pasqueron De Fommervault, Orens; Gattuso, Jean-pierre; Legendre, Louis; Johnson, Kenneth S. |
A neural network-based method (CANYON: CArbonate system and Nutrients concentration from hYdrological properties and Oxygen using a Neural-network) was developed to estimate water-column biogeochemically relevant variables in the Global Ocean. These are the concentrations of 3 nutrients [nitrate (NO3−), phosphate (PO43−) and silicate (Si(OH)4)] and 4 carbonate system parameters [total alkalinity (AT), dissolved inorganic carbon (CT), pH (pHT) and partial pressure of CO2 (pCO2)], which are estimated from concurrent in situ measurements of temperature, salinity, hydrostatic pressure and oxygen (O2) together with sampling latitude, longitude and date. Seven neural-networks were developed using the GLODAPv2 database, which is largely representative of the... |
Tipo: Text |
Palavras-chave: Neural network; Nutrients; Carbonate system; Global ocean; GLODAPv2 database; Profiling floats. |
Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00383/49467/49952.pdf |
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Gailhard, Isabelle. |
Estuaries are areas which, from their structure, their fonctioning, and their localisation, are subject to significant contribution of nutrients. One of the objectif of the RNO, the French network for coastal water quality monitoring, is to assess the levels and trends of nutrient concentrations in estuaries. A linear model was used in order to describe and to explain the total dissolved nitrogen concentration evolution in the three most important estuaries on the Chanel-Atlantic front (Seine, Loire and Gironde). As a first step, the selection of a reliable data set was performed. Then total dissolved nitrogen evolution schemes in estuary environment were graphically studied, and allowed a resonable choice of covariables. The salinity played a major role... |
Tipo: Text |
Palavras-chave: Nutriments; Estuaire; Loire; Seine; Gironde; Schéma de dilution; Modèle linéaire; Tendance; Nutrients; Estuary; Seine; Loire; Gironde; Dilution schema; Linear mode1; Trend. |
Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/00079/19070/16665.pdf |
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Nubi, O. A.; Oyatola, O.o; Bonou, F. |
In attempt to study the spatial differences in autumnal equatorial upwelling intensity relative to bio-productivity in the eastern equatorial Atlantic, oceanographic in situ data along regions 10°W, 0°E, 2.5°E and 6°E, collected in the Gulf of Guinea during autumn cruise carried out in September 2007 were analyzed. The surface mean values for temperature along 10°W, 0°E, 2.5°E and 6°E are 25.02, 26.15, 26.88 and 25.60°C, respectively. There was eastward weakening of the equatorial undercurrent from 10°W until its complete disappearance at 6°E. The highest concentration of nitrate recorded at the surface at 10°W was attributed to the shoaling pycnocline observed at this region. The surface mean values for nitrate along 10°W, 0°E, 2.5°E and 6°E are 0.37,... |
Tipo: Text |
Palavras-chave: Vertical mixing; Zonal advection; Equatorial undercurrent; Equatorial upwelling; Gulf of Guinea; Nutrients; Phytoplankton biomass; Surface enrichment.. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00621/73318/72485.pdf |
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Morand, Philippe; Merceron, Michel. |
Algal blooms, often associated with eutrophication, are common in temperate regions in coastal lagoons and estuarine areas as well as in open seas. However, because of recent changes in water flows and sediment and nutrient loads in most rivers, eutrophication phenomena are now occurring in areas previously non affected. One of its most widespread and easily recognized effects in a coastal marine ecosystem is the excessive growths and drifts of macroalgae, to such a degree that the biomass becomes a significant problem. The nutrients, notably from anthropogenic origin, constitute a significant factor in the appearance of the blooms in coastal waters. Besides a background originating from natural areas and precipitations, nutrients come from agriculture,... |
Tipo: Text |
Palavras-chave: Green tides; Macroalgae; Eutrophication; Nutrients; Black Sea. |
Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-2131.pdf |
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Condie, Scott A.; Hayes, Donna; Fulton, Elizabeth A.; Savina, Marie. |
The Clarence River Estuary is the largest estuary in southeast Australia, with an extensive floodplain encompassing multiple river channels and a large coastal lagoon. It is the focus of major commercial and recreational fisheries and there is pressure to divert its freshwater inputs for agricultural and domestic uses. We used a spatial biogeochemical model to simulate the variability and evolution of this system on timescales from days to decades over the past half century. Like most tropical and subtropical estuaries, the Clarence River Estuary is strongly influenced by river discharge, sediment and nutrient loads. Given the high nutrient loads arriving from the upper catchment, plankton biomasses in the model were typically limited by flushing through... |
Tipo: Text |
Palavras-chave: Coastal lagoon; Flushing; Land-use; Climate impacts; Nutrients; Phytoplankton; Zooplankton. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00175/28673/27113.pdf |
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Guillaud, Jean-francois; Aminot, Alain; Delmas, Daniel; Gohin, Francis; Lunven, Michel; Labry, Claire; Herbland, Alain. |
Seasonal variations in nutrient inputs are described for the main rivers (Loire and Vilaine) flowing into the northern Bay of Biscay. The river plumes are high in N/P ratio in late winter and spring, but not in the inner plume during the summer. Conservative behavior results in most nutrients entering the estuary and eventually reaching the coastal zone. Temporal and spatial aspects of phytoplankton growth and nutrient uptake in the northern Bay of Biscay distinguish the central area of salinity 34 from the plume area. The first diatom bloom appears offshore in late winter, at the edge of the river plumes, taking advantage of haline stratification and anticyclonic "weather windows." In spring, when the central area of the northern shelf is... |
Tipo: Text |
Palavras-chave: Northern Bay of Biscay; Phytoplankton; Continental shelf; Riverine inputs; Nutrients. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2354.pdf |
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Coulombier, Noémie; Nicolau, Elodie; Le Déan, Loic; Barthelemy, Vanille; Schreiber, Nathalie; Brun, Pierre; Lebouvier, Nicolas; Jauffrais, Thierry. |
Nephroselmis sp. was previously identified as a species of interest for its antioxidant properties owing to its high carotenoid content. In addition, nitrogen availability can impact biomass and specific metabolites’ production of microalgae. To optimize parameters of antioxidant production, Nephroselmis sp. was cultivated in batch and continuous culture conditions in stirred closed photobioreactors under different nitrogen conditions (N-repletion, N-limitation, and N-starvation). The aim was to determine the influence of nitrogen availability on the peroxyl radical scavenging activity (oxygen radical absorbance capacity (ORAC) assay) and carotenoid content of Nephroselmis sp. Pigment analysis revealed a specific and unusual photosynthetic system with... |
Tipo: Text |
Palavras-chave: Lutein; Natural products; Nutrients; Peroxyl radical; Siphonaxanthin. |
Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00645/75699/76604.pdf |
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Le Boyer, A.; Cambon, Gildas; Daniault, N.; Herbette, Steven; Le Cann, B.; Marie, Louis; Morin, P.. |
The Ushant tidal front is the dominant feature of the summer season hydrological structure of the Iroise Sea. It separates tidally mixed coastal waters from thermally stratified open Celtic Sea waters. This article reports on observations made in September 2007 during two short cruises that took place aboard R/V "Cotes de la Manche", and gives a general account of the physical structure of the front along one cross-frontal transect. The data set comprises data from a 4 month ADCP mooring, short CTD/fluorescence/nutrients transects, Lagrangian drifter trajectories, and HF radar surface current measurements. One finding is that the surface and bottom fronts, being affected by different dynamical influences, are not necessarily coincident in the vertical.... |
Tipo: Text |
Palavras-chave: Nutrients; Drifters; HF radars; Hydrology; Tidal mixing front; Shelf dynamics. |
Ano: 2009 |
URL: http://archimer.ifremer.fr/doc/2009/publication-6417.pdf |
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Romero, Estela; Le Gendre, Romain; Garnier, Josette; Billen, Gilles; Fisson, Cedric; Silvestre, Marie; Riou, Philippe. |
The Seine River is a highly artificialised catchment in Europe, comprising both productive agricultural areas and intense industrial and commercial activity. Due to its strategic importance, monitoring programs in the river started as early as the 1970s. The present study compiles and analyses this valuable data set (1970–2014), thoroughly describing the riverine section downstream of Paris and the estuary. We identify long-term trends and shifting patterns in nutrients and oxygen, and pay special attention to the river’s evolution after the year 2000, when the European Water Framework Directive came into force. The study has a manifest management perspective, and the results are discussed on the basis of the environmental quality standards proposed in... |
Tipo: Text |
Palavras-chave: Seine River; Water quality; Nutrients; Long-term trends; WFD; Policy. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00311/42202/41541.pdf |
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Tarkalson, D.D.; Mikkelsen, R.L.. |
Recent efforts to reduce phosphorus (P) content of corn grain fed to poultry have led to the development of low-phytic-acid corn. Research is needed to evaluate the environmental impact of the application to cropland of manure from animals fed low-phytic-acid corn. The purpose of this research was to determine P losses in runoff from a bare Piedmont soil (cecil clay loam; clayey, kaolinitic, thermic, Typic Kanhapludult) in the southeastern United States receiving surface applications of broiler litter from birds fed a low-phytic-acid corn (HAP broiler litter). The HAP litter was applied at rates of 0, 8, 16, 33, 49, 66, and 82 kg P ha-1 . Simulated rainfall was applied at a rate of 7.6 cm hr-1 on the same day the litter sources were applied to... |
Tipo: Article |
Palavras-chave: Corn / maize; Nutrients; Corn; Chemistry; Mass Import - autoclassified (may be erroneous). |
Ano: 2007 |
URL: http://eprints.nwisrl.ars.usda.gov/64/1/1229.pdf |
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Ippolito, J.A.; Stromberger, M.E.; Lentz, R.D.; Dungan, R.S.. |
The effects of biochar application to calcareous soils are not well documented. In a laboratory incubation study, a hardwood-based, fast pyrolysis biochar was applied (0, 1, 2, and 10% by weight) to a calcareous soil. Changes in soil chemistry, water content, microbial respiration, and microbial community structure were monitored over a 12-month period. Increasing biochar application rate increased the water holding capacity of the soil-biochar blend, a trait that could be beneficial under water limited situations. Biochar application also caused an increase in plant-available iron and manganese, soil carbon content, soil respiration rates, bacterial populations, and a decrease in soil nitrate-nitrogen concentration. Biochar rates of 2 and 10% altered the... |
Tipo: Article |
Palavras-chave: Calcareous soil; Nitrogen; Nutrients. |
Ano: 2014 |
URL: http://eprints.nwisrl.ars.usda.gov/1532/1/1490.pdf |
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Registros recuperados: 238 | |
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