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Auteur Leruste, A.; Villeger, S.; Malet, N.; De Wit, R.; Bec, B. doi  openurl
  Titre Complementarity of the multidimensional functional and the taxonomic approaches to study phytoplankton communities in three Mediterranean coastal lagoons of different trophic status Type Article scientifique
  Année 2018 Publication Revue Abrégée Hydrobiologia  
  Volume (down) 815 Numéro 1 Pages 207-227  
  Mots-Clés classification; Classification; disturbance; diversity; ecology; Functional entity; Functional traits; lake phytoplankton; marine-phytoplankton; patterns; size; synechococcus; Taxonomic diversity; traits  
  Résumé We used the individual-based multidimensional functional diversity and the taxonomic approaches in a complementary way to describe phytoplankton communities in three coastal lagoons with different eutrophication status in the South of France. We sampled communities during three seasons, i.e., in autumn, spring, and summer. Using classical taxonomy, 107 taxa/morphotypes were identified in the nine communities. The individual-based functional approach allowed grouping these individuals into 20 functional entities according to their values for 5 traits related to trophic adaptations (cell size, mobility, trophic regime, coloniality, and pelagic/benthic life). Some species (e.g., Prorocentrum micans) emerged in multiple functional entities, showing the importance to consider intraspecific variability. The functional description of phytoplankton communities better reflected the hydrological functioning and the different eutrophication status of the lagoons than the taxonomic approach. Specific functional adaptations were identified in the nine communities. For example, phytoplankton organisms with heterotrophic and potentially mixotrophic abilities occurred when the availability of inorganic nutrient decreased, or when organic matter and small preys were potentially the main nutrient resources. The limitation has also favored small cells highly competitive for nutrients. Using functional indices together with taxonomic description has also helped revealing important aspects of community assembly, such as competitive exclusion in summer.  
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  Langue English Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0018-8158 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2322  
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Auteur Liess, A.; Faithfull, C.; Reichstein, B.; Rowe, O.; Guo, J.; Pete, R.; Thomsson, G.; Uszko, W.; Francoeur, S.N. url  doi
openurl 
  Titre Terrestrial runoff may reduce microbenthic net community productivity by increasing turbidity: a Mediterranean coastal lagoon mesocosm experiment Type Article scientifique
  Année 2015 Publication Revue Abrégée Hydrobiologia  
  Volume (down) 753 Numéro 1 Pages 205-218  
  Mots-Clés Bacteria; Dissolved organic carbon (DOC); Ecology; Enclosure experiment; Freshwater & Marine Ecology; Microbenthos; Nutrient subsidy; Terrestrial subsidy; Zoology  
  Résumé  
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  Auteur institutionnel Thèse  
  Editeur Lieu de Publication Éditeur  
  Langue en Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0018-8158, 1573-5117 ISBN Médium  
  Région Expédition Conférence  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 1338  
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Auteur Lagarde, F.; Fiandrino, A.; Ubertini, M.; d'Orbcastel, E.R.; Mortreux, S.; Chiantella, C.; Bec, B.; Bonnet, D.; Roques, C.; Bernard, I.; Richard, M.; Guyondet, T.; Pouvreau, S.; Lett, C. url  doi
openurl 
  Titre Duality of trophic supply and hydrodynamic connectivity drives spatial patterns of Pacific oyster recruitment Type Article scientifique
  Année 2019 Publication Revue Abrégée Marine Ecology Progress Series  
  Volume (down) 632 Numéro Pages 81-100  
  Mots-Clés Coastal lagoon; Connectivity; Crassostrea gigas; Larval ecology; Oligotrophication; Recruitment; Settlement; Spatial patterns  
  Résumé The recent discovery of Pacific oyster Crassostrea gigas (also known as Magallana gigas) spatfields in a Mediterranean lagoon intensely exploited for shellfish farming (Thau lagoon) revealed significant contrasts in spatial patterns of recruitment. We evaluated the processes that drive spatial patterns in oyster recruitment by comparing observed recruitment, simulated hydrodynamic connectivity and ecological variables. We hypothesized that spatial variability of recruitment depends on (1) hydrodynamic connectivity and (2) the ecology of the larval supply, settlement, metamorphosis, survival and biotic environmental parameters. We assessed recruitment at 6-8 experimental sites by larval sampling and spat collection inside and outside oyster farming areas and on an east-west gradient, from 2012-2014. Hydrodynamic connectivity was simulated using a numerical 3D transport model assessed with a Eulerian indicator. The supply of large umbo larvae did not differ significantly inside and outside oyster farming areas, whereas the supply of pediveligers to sites outside shellfish farms was structured by hydrodynamic connectivity. Inside shellfish farming zones, unfavorable conditions due to trophic competition with filter-feeders jeopardized their settlement. In this case, our results suggest loss of settlement competence by oyster larvae. This confirms our hypothesis of top-down trophic control by the oysters inside farming zones of Thau lagoon in summer that fails to meet the ecological requirements of these areas as oyster nurseries. Knowledge of oyster dispersal, connectivity and recruitment in coastal lagoons will help local development of sustainable natural spat collection. On a global scale, our method could be transposed to other basins or used for other species such as mussels, clams or scallops, to better understand the spatial patterns of bivalve recruitment. Management of the oyster industry based on natural spat collection will help develop a sustainable activity, based on locally adapted oyster strains but also by reducing the risks of transferring pathogens between basins and the global carbon footprint of this industry.  
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  Langue en Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 0171-8630, 1616-1599 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2673  
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Auteur Lagarde, F.; Richard, M.; Bec, B.; Roques, C.; Mortreux, S.; Bernard, I.; Chiantella, C.; Messiaen, G.; Nadalini, J.-B.; Hori, M.; Hamaguchi, M.; Pouvreau, S.; ROQUE D'ORBCASTEL, E.; Tremblay, R. url  doi
openurl 
  Titre Trophic environments influence size at metamorphosis and recruitment performance of Pacific oysters Type Article scientifique
  Année 2018 Publication Revue Abrégée Marine Ecology Progress Series  
  Volume (down) 602 Numéro Pages 135-153  
  Mots-Clés Crassostrea gigas; Cryptophytes; Larval ecology; Oligotrophication; Prodissoconch II; Recruitment; Thau lagoon  
  Résumé Reproduction and recruitment of benthic invertebrates are influenced by the climate and by the ecological structure of marine ecosystems, along with local anthropogenic pressures such as eutrophication or oligotrophication. Using the Pacific oyster Crassostrea gigas as a biological model, we tested the hypothesis that the variability in prodissoconch II (PII) size (i.e. size at metamorphosis) depends on ecological functioning. Settlement and recruitment were assessed at 5 sampling sites on the French Mediterranean shellfish farmed Thau lagoon during the main summer recruitment events in 3 consecutive years (2012-2014). Hydrobiological and planktonic analyses were conducted at 3 sampling sites. Our results showed that recruitment was extremely heterogeneous, ranging from 0 to 260 ± 27 SE ind. dm-2 throughout the ecosystem and was linked with variability in PII size, which ranged from 180 to 296 µm. The annual temporal pattern of PII sizes appeared to be controlled by temperature during the settlement period, whereas the spatial pattern depended on phytoplankton biomass and on the trophic functioning of the ecosystem. Smaller PII sizes were significantly correlated with the highest phytoplankton biomass, while larger PII sizes were positively correlated with mixotrophic cryptophyte abundance. We found an inverse relationship between PII size and survival after metamorphosis, showing that recruitment success was associated with smaller PII sizes. Regional climate conditions and local trophic functioning appear to be key factors in metamorphosis and consequently contribute to recruitment heterogeneity. Further studies should be performed in other ecosystems following an oligotrophication trajectory to generalize this result.  
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  Langue en Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0171-8630, 1616-1599 ISBN Médium  
  Région Expédition Conférence  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2398  
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Auteur Chouvelon, T.; Brach-Papa, C.; Auger, D.; Bodin, N.; Bruzac, S.; Crochet, S.; Degroote, M.; Hollanda, S.J.; Hubert, C.; Knoery, J.; Munschy, C.; Puech, A.; Rozuel, E.; Thomas, B.; West, W.; Bourjea, J.; Nikolic, N. doi  openurl
  Titre Chemical contaminants (trace metals, persistent organic pollutants) in albacore tuna from western Indian and south-eastern Atlantic Oceans: Trophic influence and potential as tracers of populations Type Article scientifique
  Année 2017 Publication Revue Abrégée Sci. Total Environ.  
  Volume (down) 596 Numéro Pages 481-495  
  Mots-Clés Bioaccumulation; biscay northeast atlantic; enhanced bioaccumulation; feeding ecology; Inorganic elements; Intrinsic markers; marine food webs; mercury concentrations; merluccius-merluccius; Organic contaminants; organochlorine compounds; polychlorinated-biphenyls; stable-isotope analysis; Stable isotopes; thunnus-alalunga; Top predator  
  Résumé Albacore tuna (Thunnus alalunga) is a highly commercial fish species harvested in the world's Oceans. Identifying the potential links between populations is one of the key tools that can improve the current management across fisheries areas. In addition to characterising populations' contamination state, chemical compounds can help refine foraging areas, individual flows and populations' structure, especially when combined with other intrinsic biogeochemical (trophic) markers such as carbon and nitrogen stable isotopes. This study investigated the bioaccumulation of seven selected trace metals – chromium, nickel, copper (Cu), zinc (Zn), cadmium (Cd), mercury (Hg) and lead – in the muscle of 443 albacore tunas, collected over two seasons and/or years in the western Indian Ocean (WIO: Reunion Island and Seychelles) and in the south-eastern Atlantic Ocean (SEAO: South Africa). The main factor that explained metal concentration variability was the geographic origin of fish, rather than the size and the sex of individuals, or the season/year of sampling. The elements Cu, Zn, Cd and Hg indicated a segregation of the geographic groups most clearly. For similar sized-individuals, tunas from SEAO had significantly higher concentrations in Cu, Zn and Cd, but lower Hg concentrations than those from WIO. Information inferred from the analysis of trophic markers (delta C-13, delta N-15) and selected persistent organic pollutants, as well as information on stomach contents, corroborated the geographical differences obtained by trace metals. It also highlighted the influence of trophic ecology on metal bioaccumulation. Finally, this study evidenced the potential of metals and chemical contaminants in general as tracers, by segregating groups of individuals using different food webs or habitats, to better understand spatial connectivity at the population scale. Limited flows of individuals between the SEAO and the WIO are suggested. Albacore as predatory fish also provided some information on environmental and food web chemical contamination in the different study areas. (C) 2017 Elsevier B.V. All rights reserved.  
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  Editeur Lieu de Publication Éditeur  
  Langue English Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 0048-9697 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2139  
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