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| Registros recuperados: 369 | |
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| Cozic, Amandine. |
| A sensitive, precise and rapid analytical method was elaborated to measure simultaneously 5 volatile reduced sulfur compounds (VRSC) ; hydrogen sulfide (H2S), carbonyl sulfide (OCS), methane thiol (MeSH), dimethyl sulfide (DMS), dimethyl disulfide (DMDS). The study of VRSC in the Bay of Quiberon highlights seasonal and interannual variations of concentrations in epibenthic zone. H2S analyzed near the sediment water interface (anoxic microzones), is more elevated in summer. The OCS distribution is consistent with a predominant photodegradation in winter and a sedimentary source in summer. The variations of MeSH, DMS and DMDS are correlated with the Dinophyceae abundance. In the Seine estuary, the absence of volatile H2S in the up estuary is explained by the... |
| Tipo: Text |
Palavras-chave: Phytoplankton; Metal speciation; DMS; Sulfur; Phytoplancton; Spéciation métallique; DMS; Soufre. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/these-2687.pdf |
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| Rodier, M; Longo, S; Henry, K; Ung, A; Lo-yat, Alain; Darius, Ht; Viallon, J; Beker, B; Delesalle, B; Chinain, M. |
| Pearl farming lagoons are economically important, yet poorly studied ecosystems in French Polynesia. This paper describes a study conducted in 2016 in Takaroa (Tuamotu Archipelago), an atoll recurrently affected by harmful algal bloom (HAB) events. The objectives were to gain insight into phytoplankton community composition, identify the main bloom-forming species and investigate their potential for toxicity. A mesocosm approach was used to assess the response of phytoplankton communities to 3 nutrient treatments: Conway with Si, Si-depleted f/2 and a commercial N-P fertilizer. In total, 87 morpho-species were described from Takaroa lagoon, with dinoflagellates as the most diverse group. Diatoms (Extubocellulus sp., Cylindrotheca closterium, Nitzschia... |
| Tipo: Text |
Palavras-chave: Phytoplankton; Taxonomy; Mesocosm; Bloom-forming species; Toxicity; French Polynesian lagoons. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00499/61059/64509.pdf |
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| Echenique,Ricardo; Giannuzzi,Leda; Ferrari,Luis. |
| In April 2000, alterations in drinking water quality, such as turbidity and odors similar to those of organochloride pesticides, were detected at Bahía Blanca (Argentina). This fact was associated to reports of dermic reactions and respiratory problems in the population. Samples drawn from Paso de las Piedras reservoir, two water treatment plants of at inlet and outlet points and at several particular houses were analyzed. Total phytoplankton in the reservoir varied between 49440 and 84832 cells.ml-1, while dominant species was, Anabaena circinalis. Efficiency to remove microorganisms (ER) by the treatment plants considering cell number of total phytoplankton was analyzed. Bacteriological analysis, qualitative and quantitative studies of phytoplankton,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Cyanobacteria; Phytoplankton; Blooms; Biogenic odour compounds. |
| Ano: 2006 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S1851-37432006000200001 |
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| Escalas, Arthur; Catherine, Arnaud; Maloufi, Selma; Cellamre, Maria; Hamlaoui, Sahima; Yepremian, Claude; Louvard, Clarisse; Trousselier, Marc; Bernard, Cécile. |
| Evaluating the causes and consequences of dominance by a limited number of taxa in phytoplankton communities is of huge importance in the current context of increasing anthropogenic pressures on natural ecosystems. This is of particular concern in densely populated urban areas where usages and impacts of human populations on water ecosystems are strongly interconnected. Microbial biodiversity is commonly used as a bioindicator of environmental quality and ecosystem functioning, but there are few studies at the regional scale that integrate the drivers of dominance in phytoplankton communities and their consequences on the structure and functioning of these communities. Here, we studied the causes and consequences of phytoplankton dominance in 50... |
| Tipo: Text |
Palavras-chave: Dominance; Phytoplankton; Co-occurrence network; Community cohesion; Community functioning; Periurban waterbodies. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00508/61962/66081.pdf |
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| Marshall, Hg; Alden, Rw. |
| Long term trends in the phytoplankton of the lower Chesapeake Bay were identified using flow corrected and uncorrected data sets, with 22 of 23 significant trends similar under both conditions. The major trends between 1985-1992 were for: 1) reduced phytoplankton concentrations; 2) decreasing numbers of phytoplankton taxa during spring, summer and fall months; and 3) seasonally mixed trends for diatom abundance in waters below the pycnocline, with spring months having decreasing densities, and increasing abundance trends in November and December. The flow patterns had different effects on the trends. Flow diminished the magnitude of the trends for total phytplankton concentrations, so these trends were greater in the flow corrected data. There were mixed... |
| Tipo: Text |
Palavras-chave: Phytoplankton; Chesapeake Bay; Trends; Flow. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00093/20383/18051.pdf |
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| Savoye, N; Aminot, Alain; Treguer, Paul; Fontugne, M; Naulet, N; Kerouel, Roger. |
| Two cruises (April and June 1997) were carried out in the Bay of Seine, a nitrate- and ammonium-enriched ecosystem of Western Europe, to identify the major mechanisms that control delta(15)N and VC in spring particulate organic matter (POM). Particulate organic nitrogen (PON) delta(15)N ranged between 0.8 and 5.2parts per thousand in April and between 2.2 and 6.2parts per thousand in June, while particulate organic carbon (POC) delta(13)C ranged between -24.3 and -19.7parts per thousand, and between -20.0 and -16.2parts per thousand during the same periods. During spring 1997, POM was highly dominated by autochthonous phytoplankton. It is shown that the variation of PON delta(15)N is due to both nitrate mixing between river and marine waters and... |
| Tipo: Text |
Palavras-chave: C and N stable isotopes; Phytoplankton; Coastal ecosystem; Nitrate utilization; Bay of Seine. |
| Ano: 2003 |
URL: http://archimer.ifremer.fr/doc/00000/10645/7593.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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| Morelle, Jerome; Schapira, Mathilde; Claquin, Pascal. |
| Exopolysaccharides (EPS) play an important role in the carbon flux and may be directly linked to phytoplankton and microphytobenthos production, most notably in estuarine systems. However the temporal and spatial dynamics of estuarine EPS are still not well understood, nor how primary productivity triggers this variability at these different scales. The aim of this study was to investigate the primary productivity of phytoplankton and EPS dynamics in the Seine estuary over a tidal cycle in three different haline zones over two contrasted seasons. The other objectives was to investigate the origin of pools of soluble carbohydrates (S-EPS) and transparent exopolymeric particles (TEP) in phytoplankton, microphytobenthos or other compartments. High frequency... |
| Tipo: Text |
Palavras-chave: Phytoplankton; Microphytobenthos; PAM fluorometer; Electron transport rate. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00400/51132/51898.pdf |
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| Morelle, Jérôme. |
| The estuaries play an important ecological role and are the site of many human activities because of their strategic position at the interface between continental and marine waters. Seine estuary is characteristic of large anthropized estuaries. Long-term management requires better knowledge of the spatial and temporal dynamics of the estuarine food webs. Phytoplankton and microphytobenthos are the main contributor of primary production (PP) in these ecosystems and are at the basis of trophic food webs. These compartments are often reduced to the chlorophyll concentration and their productivity has never been measured along the Seine estuary. The objective of this study was to estimate the PP of these compartments along the salinity gradient. In order to... |
| Tipo: Text |
Palavras-chave: PAM; ETR; 13C; TEP; EPS; Exopolymeric substances; Phytoplankton; Microphytobenthos; Transparent Exopolymeric Particles. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00498/60965/64373.pdf |
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| Registros recuperados: 369 | |
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