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Registros recuperados: 10 | |
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Strady, Emilie; Harmelin-vivien, Mireille; Chiffoleau, Jean-francois; Veron, Alain; Tronczynski, Jacek; Radakovitch, Olivier. |
The transfer of 210Po and 210Pb in the food web of small pelagic fishes (from phytoplankton and zooplankton to anchovy Engraulis encrasicolus and sardine Sardina pilchardus) is investigated in the Gulf of Lion (GoL). We present original data of 210Po and 210Pb activity concentrations, C and N stable isotope ratios, measured (i) from different size classes of phytoplankton and zooplankton during spring and winter in different environments of the GoL, and (ii) in two fish species. Significant spatial patterns based on 210Po, 210Pb activity concentrations and 210Po/210Pb ratios in the different plankton size classes are evidenced by hierarchical clustering, both in spring and winter. This variability, also observed for C and N stable isotopes ratios, is... |
Tipo: Text |
Palavras-chave: Po-210; Pb-210; Phytoplankton; Zooplankton; Pelagic fishes; Mediterranean Sea. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00255/36609/35264.pdf |
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Lison De Loma, Thierry; Harmelin-vivien, Mireille; Naim, Odile; Fontaine, Marie France. |
There has, as yet, been little study of nutrient disturbance and its consequences on the functional biology of primary consumers in coral reefs. The processing of epilithic algal communities by the damselfish Stegastes nigricans was investigated at La Reunion, at two sites of a fringing reef, oligotrophic for one and eutrophic for the other. Differences between sites were analyzed in quantifying organic matter, organic carbon, nitrogen, and organic 'nutrients' (carbohydrate, lipid and protein) in the algal food, the digestive contents and the faeces of S. nigricans. In the disturbed site, algal turfs and digestive contents presented significantly higher organic matter, organic carbon, nitrogen and organic nutrient values. Absorption efficiency of total... |
Tipo: Text |
Palavras-chave: Régime herbivore; Stegastes; Récif corallien; Eutrophisation; La Réunion; Herbivory; Stegastes; Coral reef; Eutrophication; La Reunion. |
Ano: 2000 |
URL: http://archimer.ifremer.fr/doc/00323/43376/42835.pdf |
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Cresson, Pierre; Ruitton, Sandrine; Ourgaud, Melanie; Harmelin-vivien, Mireille. |
A large complex of artificial reefs was deployed in the Bay of Marseilles, North-Western Mediterranean, for the enhancement of commercial fisheries stocks. Carbon and nitrogen stable isotope and stomach content analyses were performed on 23 fish species collected on the artificial reefs to assess their trophic position and feeding behaviour. Results indicated that fish diets were not modified on the artificial reefs compared to natural environments, nor was the structure of their trophic network. Artificial reefs, with their complex design, provide diverse and abundant food sources for fishes. Ranges of delta C-13 and delta N-15 of artificial reef fishes were comparable to those recorded in natural Mediterranean environments, with a similar trophic... |
Tipo: Text |
Palavras-chave: Artificial reefs; Fish diet; NW Mediterranean; Stable isotopes; Stomach content; Trophic level. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00186/29708/28188.pdf |
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Harmelin-vivien, Mireille; Bodiguel, Xavier; Charmasson, Sabine; Loizeau, Veronique; Mellon, Capucine; Tronczynski, Jacek; Cossa, Daniel. |
Consumption of marine organisms represents one of the main exposure sources of contaminants for human populations. To obtain a global view of the contamination in commercial fish in the NW Mediterranean Sea, we analysed four types of priority contaminants (PCBs, PBDEs, Hg and Cs-137) in the European hake, Merluccius merluccius, from the Gulf of Lions in relation with organism's trophic level (delta N-15). All contaminants presented a significant increase in concentration in hake muscle with trophic level. However, obvious differences between contaminants were evidenced. Biomagnification factors (BMF and FWMF) along the hake food web were higher for Hg and CB-153 than for BDE-47 and Cs-137, and increase in contaminant concentration with trophic level... |
Tipo: Text |
Palavras-chave: Persistent organic pollutants; Mercury; Cs-137; Merluccius merluccius; Mediterranean. |
Ano: 2012 |
URL: http://archimer.ifremer.fr/doc/00085/19583/17484.pdf |
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Cresson, Pierre; Ruitton, Sandrine; Harmelin-vivien, Mireille. |
Suspension-feeders predominate in the vast majority of the coastal marine benthic ecosystems, with several species co-occurring at low spatial scale. Understanding how these species cope with competition for trophic resources has been the core of numerous studies, mostly in coastal shallow systems where food supplies are diverse and abundant. Oligotrophic systems have received less attention. The aim of the present study was thus to investigate the trophic relationships established between 9 suspension feeders collected in an oligotrophic zone (Bay of Marseille, French Mediterranean). Species displayed similar isotopic ratios, consistently with the use of one main source, identified as nanophytoplankton and diazotrophic bacteria as the δ15N values were... |
Tipo: Text |
Palavras-chave: Suspension feeders; Isotopic niche; Mediterranean; Oligotrophy; Resource sharing mechanisms. |
Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00301/41203/40363.pdf |
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Belloni, Bruno; Sartoretto, Stephane; Cresson, Pierre; Bouchoucha, Marc; Guillou, Gael; Lebreton, Benoit; Ruitton, Sandrine; Harmelin-vivien, Mireille. |
The coralligenous ecosystem is one of the biodiversity hotspots in the Mediterranean Sea. This study aims at determining (i) the organic matter (OM) sources at the base of the food web in a coralligenous ecosystem near Marseille (Cap Caveau, Frioul Island) and (ii) the global functional structure of its community. For that purpose, C and N stable isotope analyses were performed on 78 compartments or species collected in this habitat between 30 and 40 m depth. Results suggested that the pelagic particulate organic matter (POM), mainly composed of phytoplankton, was the main OM source fuelling coralligenous food webs, followed by sedimented organic matter (SOM) and some macrophytes. At least three level of consumers were identified from... |
Tipo: Text |
Palavras-chave: Food webs; Coralligenous ecosystem; Stable isotopes; Carbon; Nitrogen. |
Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00483/59511/62396.pdf |
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Biton-porsmoguer, Sebastian; Banaru, Daniela; Boudouresque, Charles F.; Dekeyser, Ivan; Bouchoucha, Marc; Marco-miralles, Francoise; Lebreton, Benoit; Guillou, Gael; Harmelin-vivien, Mireille. |
Pelagic sharks (blue shark Prionace glauca and shortfin mako Isurus oxyrinchus) caught by long-line Spanish and Portuguese fleets in the NE Atlantic, were sampled at Vigo fish market (Spain) for total mercury (Hg) analysis. Hg concentration in white muscle increased with size and weight in both species, but at a higher rate in shortfin mako than in the blue shark. No difference was found with sex, year and season. Spatial variation was observed in the blue shark with higher Hg values in the North of the Azorean archipelago, but not in the shortfin mako. These high-level predators are particularly susceptible to bioaccumulate contaminants (Hg) in their tissues (muscle). However, a significant positive relationship between Hg concentration and trophic level... |
Tipo: Text |
Palavras-chave: Mercury; Pelagic sharks; Blue shark; Shortfin mako; Long-line fishery; NE Atlantic. |
Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00413/52492/56296.pdf |
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Tiano, Marion; Tronczynski, Jacek; Harmelin-vivien, Mireille; Tixier, Celine; Carlotti, Francois. |
PCB levels in plankton were investigated in the Bay of Marseille, Western Mediterranean Sea, between September 2010 and October 2011. Concentrations of PCB congeners (CB 18, CB 52, CB 101, CB 118, CB 138, CB 153, CB 180) were determined in three plankton size-classes (60–200, 200–500 and 500–1000 μm) together with different parameters: chlorophyll content, plankton dry-weight biomass, carbon and nitrogen stable isotope ratios and plankton-community structure. The ∑PCB7 concentrations ranged between 14.2 and 88.1 ng g−1 d.w., for all size classes and all sampling periods. The results do not show the biomass dilution effect and indicate moderate but significant biomagnification with plankton trophic position estimated by δ15N signatures. Equilibrium with... |
Tipo: Text |
Palavras-chave: PCBs; Phytoplankton; Zooplankton; Bioaccumulation; Coastal; Bay of Marseille. |
Ano: 2014 |
URL: https://archimer.ifremer.fr/doc/00218/32881/31371.pdf |
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Mellon, Capucine; Harmelin-vivien, Mireille; Metral, Luisa; Loizeau, Veronique; Mortreux, Serge; Roos, David; Fromentin, Jean-marc. |
The European hake, Merluccius merluccius, is an important resource for Mediterranean fisheries. This study focuses on juvenile and adult hake feeding ecology in the Gulf of Lions, using information from scientific surveys carried out during two seasons and three years (2004-2006). Stomach content and stable isotope (ä15N, ä13C) analyses were performed, and the main factors explaining variations in ä15N were investigated using GLMs. In the Gulf of Lions, hake mostly fed on crustaceans and fish and a dominant piscivorous regime was reached at 15 cm total length. Pelagic fish (sardine, anchovy and small blue whiting) were the main source of prey (40%-80%) and cannibalism was low (<5%). The results confirmed that hake is an opportunistic feeder and also... |
Tipo: Text |
Palavras-chave: Foodweb; GLM; Habitat; Merluccius merluccius; Predator-prey relationships; Stable isotopes; Stomach contents. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00360/47091/47016.pdf |
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Registros recuperados: 10 | |
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