Consulta: creatorFacets:"Herbland, Alain"
Registros recuperados: 24
Data/hora: 06/06/2024 10:15:49

Does the nutrient enrichment of the equatorial upwelling influence the size structure of phytoplankton in the Atlantic Ocean?
Provedor de dados: 5
Autores: Herbland, Alain; Le Bouteiller, A; Raimbault, P.
A study of the size structure of chlorophyll a (Chla) covering the major part of the equatorial Atlantic Ocean from 5 degree N to 5 degree S leads to the conclusion that seasonal nutrient enrichment in the open eastern equatorial Atlantic does not drastically affect the size distribution of the primary producers: 90% of the total Chla is everywhere contained in the &lt; 20 mu m fraction on the average. In the coastal upwelling near Dakar, this percentage is less than 60%, for the same range of chla concentrations. In the equatorial region the percentage of &lt; 1 mu m Chla is the same in the deep chlorophyll maximum located at the top of the nitracline during the warm season and in the subsuperficial maximum of the upwelling.
Tipo: Text
Ano: 1987
URL: http://archimer.ifremer.fr/doc/00267/37855/35936.pdf

Spatial and temporal extension of eutrophication associated with shrimp farm wastewater discharges in the New Caledonia lagoon
Provedor de dados: 5
Autores: Thomas, Yoann; Courties, Claude; El Helwe, Yasmin; Herbland, Alain; Lemonnier, Hugues.
Shrimp farming in New Caledonia typically uses a flow-through system with water exchange rates as a tool to maintain optimum hydrological and biological parameters for the crop. Moreover, the effluent shows hydrobiological characteristics (minerals, phytoplankton biomass and organic matter) significantly higher than that of the receiving environment. Separate surveys were carried out in a bay (CH Bay) with a medium-size intensive farm (30 ha) (PO) and in a mangrove-lined creek (TE Creek) near a larger semi-intensive farm (133 ha) (SO). Net loads of nitrogen exported from the semi-intensive farm and the intensive farm amounted to 0.68 and 1.36 kg ha(-1) day(-1), respectively. At CH Bay, discharge effects were spatially limited and clearly restricted to...
Tipo: Text
Palavras-chave: Environmental impact; Shrimp farming; Eutrophication; Flow cytometry; New Caledonia.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00014/12527/9882.pdf

Foraminiferal assemblages: tools for assessment of shrimp pond conditions
Provedor de dados: 5
Autores: Debenay, Jean-pierre; Della Patrona, Luc; Herbland, Alain; Goguenheim, Hemitti; Peignon, Jean-marie.
Meiofauna is a functional group made of small benthic metazoans 45 to 500µm in size. Although protista, foraminifera living in this kind of environment are often put in to the meiofauna. Meiofauna has been studied in New Caledonia for its double role as biological indicator for monitoring pond health status and as shrimp forage. Suitability of EOM (easily oxidized material), SOD(sediment oxygen demand),as new biochemical tools for monitoring shrimp pond health was assessed in an environmental survey aiming to assess the role of the water/sediment interface in the occurrence of the summer syndrome vibriosis. EOM, SOD and redox were correlated with shrimp survivals. Lowest meiofauna biomass and abundance were concomitantly found in the most polluted station....
Tipo: Text
Ano: 2009
URL: http://archimer.ifremer.fr/doc/00198/30876/29244.pdf

Pyruvate kinase activity as index of carbohydrate assimilation by mesozooplankton: an early field implementation in the Bay of Biscay, NE Atlantic
Provedor de dados: 5
Autores: Bergeron, Jean-pierre; Herbland, Alain.
Estimates of carbohydrate assimilation within the mesozooplankton compartment are a fundamental concern in oceanography because they give a general expression of the biologically-regulated incorporation of metabolic fuel produced from inorganic nutrients by phytoplankton in the sea. A new tool is proposed for the assessment of such processes. It is based on the measurement of the activity of an enzyme, pyruvate kinase (PK), on samples of the whole mesozooplankton community. Here, the results are presented of an early attempt at such an implementation in the Bay of Biscay (north-east Atlantic) in springtime. A main area situated in front of an estuary (Gironde) has been extensively studied-the same sampling grid was covered on three occasions (two 20 day...
Tipo: Text
Palavras-chave: Bay of Biscay; Zooplankton; Phytoplankton; Pyruvate kinase; Carbohydrate.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/publication-452.pdf

Nutrient and microbial dynamics in eutrophying shrimp ponds affected or unaffected by vibriosis
Provedor de dados: 5
Autores: Lemonnier, Hugues; Courties, Claude; Mugnier, Chantal; Torreton, Jean-pascal; Herbland, Alain.
A field survey was conducted on two intensive shrimp farms using similar technical practices: one (DF) historically affected by a vibriosis, the other (HC) in which the pathogen has been observed although no mortality event has occurred. Because historical data suggest that eutrophication process may directly or indirectly play a role in the disease outbreak, we focussed our research on its dynamics. A higher variability of the phytoplanktonic compartment linked to an imbalance in the molar N:P ratio was observed in farm DF compared to farm HC, implying a modification on the linkage between the bacteria and phytoplankton compartments at DF. The beginning of the mortality outbreak at DF followed a shift from picoto nanophytoplankton. The organic matter...
Tipo: Text
Palavras-chave: Aquaculture; Shrimp; Eutrophication; Ecosystem shift; Phytoplankton; Vibriosis.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00002/11368/8119.pdf

Satellite and in situ observations of a late winter phytoplankton bloom, in the northern Bay of Biscay
Provedor de dados: 5
Autores: 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

The impact of easily oxidized material (EOM) on the meiobenthos: Foraminifera abnormalities in shrimp ponds of New Caledonia; implications for environment and paleoenvironment survey
Provedor de dados: 5
Autores: Debenay, J.p.; Della Patrona, Luc; Herbland, Alain; Goguenheim, H.
This study was carried out in shrimp ponds from New Caledonia, in order to determine the cause of the exceptional proportion of abnormal tests (FAI) (often &gt;50%, sometimes &gt;80%). FAI was positively correlated to the quantity of easily oxidized material (EOM) deposited on the bottom of the ponds and to the sediment oxygen demand, and negatively correlated to redox. These results suggest that a very high FAI is a potential indicator for great accumulations of native organic matter, leading to a high sediment oxygen demand. When studying ancient sediments in core samples, exceptional abundances of abnormal tests may indicate periods of high accumulation of EOM, and therefore of oxygen depletion. This finding should help in better management of...
Tipo: Text
Palavras-chave: SW Pacific; Bioindicators; Organic matter; Shrimp ponds; Deformations; Foraminifera.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6955.pdf

The stability of the spatial distribution of the pelagic stages of sole as explained by the trajectories of ARGOS satellite
Provedor de dados: 5
Autores: Koutsikopoulos, Constantin; Herbland, Alain.
The studies of the pelagic stages of Sole (Solea vulgaris , Quensel) in the northern part of the Bay of Biscay are strongly influenced by the recent concepts concerning the importance of the physical processes in the evolution of marine populations. The investigations of the linkage between water masses circulation and year-class strength started in 1986 with the deployment of 3 ARGOS satellite tracked drifters at different depths in parallel with the ichthyoplanktonic surveys. The trajectory of the 7 m drifter (tracking the water masses above the pycnocline) is related to the wind. This drifter leaves the sector of the study after 10 days. After 40 days of variable environmental conditions, the 34 m drifter (situated below the density gradient) was only...
Tipo: Text
Ano: 1987
URL: https://archimer.ifremer.fr/doc/00482/59344/62138.pdf

Phytoplankton and bacterial alkaline phosphatase activities in relation to phosphate and DOP availability within the Gironde plume waters (Bay of Biscay)
Provedor de dados: 5
Autores: 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

Les sols des fonds de bassins et leur gestion durant les assecs. Etat des connaissances
Provedor de dados: 5
Autores: Della Patrona, Luc; Brun, Pierre; Herbland, Alain.
Shrimp culture in New Caledonia has developed according to the "intensified" semi-intensive model which uses ponds that stretch over several hectares. Local shrimp farms are for the most part installed in "tannes", barren, highly saline areas of the back mangrove forest. These areas generally have impermeable silty clay soils that have biogeochemical features particularly appropriate for benthic life and are often immersed by tides. During the six months of the grow-out phase, the "pond ecosystem" undergoes an increase in potential, progressing from an initial state of "natural lagoon" to a "grow-out pond" that is highly enriched with degrading organic matter....
Tipo: Text
Ano: 2007
URL: http://archimer.ifremer.fr/doc/2007/rapport-4399.pdf

A whirling ecosystem in the equatorial Atlantic
Provedor de dados: 5
Autores: Menkes, Christophe; Kennan, Sc; Flament, Pierre; Dandonneau, Y; Masson, S; Biessy, B; Marchal, E; Eldin, G; Grelet, J; Montel, Y; Morliere, A; Lebourges-dhaussy, A; Moulin, C; Champalbert, G; Herbland, Alain.
[1] The equatorial Pacific and Atlantic oceans exhibit remarkable meridional undulations in temperature and chlorophyll fronts visible from space over thousands of kilometers and often referred to as tropical instability waves. Here, we present new observations of an ecosystem ranging through three trophic levels: phytoplankton, zooplankton and small pelagic fish whirling within a tropical vortex of the Atlantic ocean and associated with such undulations. Cold, nutrient and biologically rich equatorial waters are advected northward and downward to form sharp fronts visible in all tracers and trophic levels. The equatorward recirculation experiences upwelling at depth, with the pycnocline and ecosystem progressively moving toward the surface to reconnect...
Tipo: Text
Ano: 2002
URL: http://archimer.ifremer.fr/doc/00000/10049/9584.pdf

Conditions d'apparition de densités accrues de dinoflagellés Dinophysis dans le pertuis d'Antioche et les eaux adjacentes. Campagnes Dinopertuis 89
Provedor de dados: 5
Autores: Delmas, Daniel; Herbland, Alain; Maestrini, Serge; Mornet, Francoise; Morand, Philippe; Spano, Anna-maria; Burgeot, Thierry; Margat, Sylvie; Charpentier, Gabriel; Fillon, Alain; Leguay, Didier; Thomas, Gerard; Bacher, Cedric; Heral, Maurice; Prou, Jean.
Environmental and species features which lead to increases in cell density of the D.S.P. Dinoflagellate Dinophysis in inshore and offshore waters of the île de Ré - île d'Oléron area, France (cruises "Dinopertuis89"). Four weekly sampling series have been carried out, within 10 May – 31 May 1989, at 24 stations located from inshore to offshore waters of the "île de Ré" - "île d’Oléron" area, with the aim to investigate (i) whether Dinophysis increases in cell density occur first in offshore waters and then, eventually, are pushed to the coast, or develop simultaneously in the whole area, and (ii) whether there are some environmental conditions which are related to Dinophysis blooms. Depths of sampling have been stated on the bas is of STD profiles. All...
Tipo: Text
Ano: 1990
URL: http://archimer.ifremer.fr/doc/00174/28532/26916.pdf

Satellite-derived parameters for biological modelling in coastal waters: Illustration over the eastern continental shelf of the Bay of Biscay
Provedor de dados: 5
Autores: 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

Eutrophication in a tropical pond: Understanding the bacterioplankton and phytoplankton dynamics during a vibriosis outbreak using flow cytometric analyses
Provedor de dados: 5
Autores: Lucas, Ronan; Courties, C.; Herbland, Alain; Goulletquer, Philippe; Marteau, Anne-laure; Lemonnier, Hugues.
In tropical shrimp ponds, the increasing of feed input, concomitantly with the stocking shrimp biomass, induces an eutrophication of the ecosystem. Although difficult to maintain, its stability is required to guarantee the success of the culture. A 110-day period of phytoplankton and bacterioplankton stock and dynamics in an earthen pond (1.2 ha area, 1 m depth) was monitored using flow cytometry to provide baseline information on community characteristics and ecosystem instability. Seven autotrophic cell types were identified over the whole sampling period. Prokaryotic cells included Synechococcus sp., a group named UNK which presented an atypical new flow cytometric signature and picoeukaryotes (PEUK). Nanophytoplankton cells were represented by 4...
Tipo: Text
Palavras-chave: Tropical shrimp aquaculture; Ecosystem shift; Phytoplankton; Bacterioplankton; Vibrio; Flow cytometry.
Ano: 2010
URL: http://archimer.ifremer.fr/doc/00029/14068/11312.pdf

La culture de phytoplancton dans les bassins aquacoles - Aspects théoriques et appplications pratiques
Provedor de dados: 5
Autores: Herbland, Alain.
Tipo: Text
Ano: 2007
URL: http://archimer.ifremer.fr/doc/00082/19286/16881.pdf

Environmental conditions which lead to increase in cell density of the toxic dinoflagellates Dinophysis spp. in nutrient-rich and nutrient-poor waters of the French Atlantic coast
Provedor de dados: 5
Autores: Delmas, Daniel; Herbland, Alain; Maestrini, Serge.
From 22 April to 19 June 1990, 7 stations located off La Rochelle, France, from near-shore ('bassin Marennes-Oleron') to offshore waters (50 m depth contour) were visited 8 times, with the aim of determining whether the toxic dinoflagellates Dinophysis spp. increase in cell density in nutrient-poor offshore water, in nutrient-rich inshore waters, or both, and to determine their vertical distribution in relation to stratification. Temperature stratification developed offshore, but not inshore. In April, few Dinophysis spp. were present offshore and none inshore. In late May, up to 15 X 10(3) cells l(-1) were recorded in the 10 to 15 m layer offshore, whereas inshore waters contained only a few cells l(-1). In late May, a short period of wind partly modified...
Tipo: Text
Ano: 1992
URL: http://archimer.ifremer.fr/doc/00190/30141/28772.pdf

"Summer syndrome" in Litopenaeus stylirostris grow out ponds in New Caledonia: zootechnical and environmental factors
Provedor de dados: 5
Autores: Lemonnier, Hugues; Herbland, Alain; Salery, Lucas; Soulard, Benoit.
The "Summer Syndrome", a septicemic vibriosis caused by Vibrio nigripulchritudo, is responsible for one of the two main seasonal mortalities which affect shrimp aquaculture in New Caledonia. It was identified for the first time in December 1997 in an intensive shrimp farm (called farm DF) and has been enzootic ever since. The "Summer syndrome" affects shrimp during warm-season growout. Although the geographic area concerned is limited, it is a potential threat for the industry in that the disease could spread. Analysis of grow out data from 1991 to 2002 in this farm was carried out in order to characterize the disease and the environmental conditions in relation to mortality. Results of farm DF were compared to data from farms not affected by the disease...
Tipo: Text
Palavras-chave: Eutrophication; Pond management; Vibriosis; Shrimp culture ponds.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-1868.pdf

Hydro-plankton characteristics and their relationship with sardine and anchovy distributions on the French shelf of the Bay of Biscay
Provedor de dados: 5
Autores: Petitgas, Pierre; Masse, Jacques; Bourriau, Paul; Beillois, Pierre; Bergeron, Jean-pierre; Delmas, Daniel; Herbland, Alain; Koueta, Noussithe; Froidefond, Jean-marie; Santos, Maria.
The spatial pattern in hydro-plankton and fish distributions and their relationship were analysed based on the spring 2000 fisheries acoustic survey. The importance of this survey was that it was a multi-disciplinary platform which collected an extensive set of parameters in the hydro-plankton leading to a potentially finer description of hydro-plankton conditions and fish habitats. More than 50 variables were measured on a grid of stations, in four compartments of the ecosystem: hydrology, nutrients, primary producers and meso-zooplankton. First, a joint analysis of all hydro-plankton compartments was performed using multiple factor analysis (MFA). The method was used to estimate a compromise factorial space common to all compartments in which the...
Tipo: Text
Palavras-chave: Fish environment relationship; Hydro plankton; Habitats; Multiple factor analysis; Spatial pattern.
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/publication-3961.pdf

Impact de la crevetticulture calédonienne sur l'environnement : état des lieux, recherche de traceurs des effluents et définition d'un programme de recherche pluriannuel
Provedor de dados: 5
Autores: Lemonnier, Hugues; Thomas, Yoann; Legrand, Alexandre; Martin, Jean-louis; Herbland, Alain.
In the booming context of shrimp culture in French Caledonia, some research actions need to be considered in order (i) to make sure this production will not impact the quality and biodiversity of the coastal environment it is contingent upon (ii) for the field to highlight, based on objective bases, its good "environmental image", for an efficient commercialization of its products. In the framework of the MOM project, a number of actions have been carried out: Action 1: A bibliographical synthesis of the impact of shrimp culture on coastal environment has been conducted, taking into account the works carried out throughout the world and in French Caledonia in order to draw the main issues the Territory will have to deal with. It seems necessary to start...
Tipo: Text
Ano: 2006
URL: http://archimer.ifremer.fr/doc/2006/rapport-6593.pdf

Behaviour of arsenic on the continental shelf off the Gironde estuary: role of phytoplankton in vertical fluxes during spring bloom conditions
Provedor de dados: 5
Autores: Michel, Pierre; Boutier, Bernard; Herbland, Alain; Averty, Bernard; Artigas, Lf; Auger, Dominique; Chartier, E.
The arsenic (As) cycle in the marine environment is known to be sensitive to biological activity. Within the scope of the National Coastal Oceanography Program, we undertook a specific study of the behaviour of this element in a water column on the continental shelf of the Bay of Biscay off the Gironde estuary during two oceanographic cruises conducted in May 1994 and May 1995. Various chemical forms were measured: arsenite (As3), at-senate (As5), monomethylarsenic (MMA), dimethylarsenic (DMA) and dissolved total As after ultraviolet mineralization. The net flux of total As from the Gironde estuary was evaluated as well as its effect on the concentration in surface marine waters. The vertical profiles in the coastal zone during a period of active primary...
Tipo: Text
Palavras-chave: Arsenic; Phytoplankton; Speciation; Gironde plume; Biscay Bay.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/1998/publication-851.pdf

The role of phosphorus on planktonic production of the Gironde plume waters in the Bay of Biscay
Provedor de dados: 5
Autores: Labry, Claire; Herbland, Alain; Delmas, Daniel.
More and more studies emphasize the status of phosphorus (P) as the principal limiting nutrient of phytoplankton growth, especially in coastal waters under the influence of freshwater discharges. The purpose of the present paper is to investigate the role of P on planktonic production in the waters influenced by the Gironde discharges; the Gironde being one of the two largest rivers on the French Atlantic coast. The survey is based on several cruises made in 1998 and 1999. Two different patterns were observed for waters with salinity below and above 34.5. For waters with salinity &lt;34.5. P was found to be the first limiting nutrient of winter and spring phytoplankton blooms, based on undetectable phosphate (&lt;20 nM), high NO3 : PO4 ratios, typically...
Tipo: Text
Palavras-chave: Bay of Biscay; River plume; Salinity; Water quality analysis; Phytoplankton; Planktonic production.
Ano: 2002
URL: http://archimer.ifremer.fr/doc/2002/publication-690.pdf

Seasonal variation of riverine nutrient inputs in the northern Bay of Biscay (France), and patterns of marine phytoplankton response
Provedor de dados: 5
Autores: 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

Phytoplankton spring bloom of the Gironde plume waters in the Bay of Biscay: early phosphorus limitation and food-web consequences
Provedor de dados: 5
Autores: Herbland, Alain; Delmas, Daniel; Laborde, P; Sautour, B; Artigas, F.
During the spring 1995 (2-25 May), a cruise was carried on the RV Poseidon (Germany) on the continental shelf of the south Bay of Biscay. The objective was a comprehensive study of the planktonic food web within the Gironde plume waters. In these waters phosphate was present at very low concentrations (undetectable to &lt; 0.1 mu mol.L-1), whereas nitrate, silicate and ammonium concentrations were much higher (several mu mol.L-1 for nitrate and silicate and 0.5 to 1.0 mu mol.L-1 for ammonium). The size distribution of the phytoplankton biomass (estimated from chlorophyll a measurements by high performance liquid chromatography) and primary production (measured by C-14 in situ method) showed a great proportion of small (40 to 70 % &lt; 3 mu m) and active...
Tipo: Text
Palavras-chave: Phosphate; Phytoplancton; Facteur limitant; Estuaire; Eau côtière; Phosphate; Phytoplankton; Limiting factor; Estuarine water; Coastal water.
Ano: 1998
URL: http://archimer.ifremer.fr/doc/1998/publication-850.pdf

Initiation of winter phytoplankton blooms within the Gironde plume waters in the Bay of Biscay
Provedor de dados: 5
Autores: Labry, Claire; Herbland, Alain; Delmas, Daniel; Laborde, P; Lazure, Pascal; Froidefond, J; Jegou, Anne-marie; Sautour, B.
Thermostratification and seasonal Light increase are generally considered the first causes of phytoplankton spring blooms in temperate waters. The objective of this study is to confirm the existence of winter phytoplankton blooms, responsible for the early exhaustion of phosphate, within the Gironde plume waters (southeast Bay of Biscay), and to understand what may initiate them so early. Two cruises, BIOMET 2 and BIOMET 3, were carried out respectively in early (8 to 21 January) and late winter 1998 (25 February to 11 March). An increase of phytoplankton biomass (chl a) between the 2 cruises and non-conservative nutrients observed in late winter confirm an early phytoplankton growth both in the Gironde plume and adjacent oceanic waters. Among factors that...
Tipo: Text
Palavras-chave: Vertical attenuation coefficient; Halostratification; Light availability; Winter blooms.
Ano: 2001
URL: http://archimer.ifremer.fr/doc/2001/publication-810.pdf