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Auteur Bodin, N.; Lesperance, D.; Albert, R.; Hollanda, S.; Michaud, P.; Degroote, M.; Churlaud, C.; Bustamante, P. doi  openurl
  Titre Trace elements in oceanic pelagic communities in the western Indian Ocean Type Article scientifique
  Année 2017 Publication Revue Abrégée Chemosphere  
  Volume 174 Numéro Pages 354-362  
  Mots-Clés atlantic-ocean; blue marlin; Environmental risk assessment; makaira-nigricans; Marine fish; Mediterranean Sea; Mercury; mercury content; North Pacific; risk-assessment; Seafood; Selenium; swordfish xiphias-gladius; Tuna fisheries' bycatch  
  Résumé The mineral composition of target and non-target pelagic fish caught by purse-seiners and longliners in the western-central Indian Ocean was determined. From the 10 essential elements analysed, selenium and zinc showed the highest concentrations in swordfish and blue marlin while Indian mackerel appeared as a good source of copper, iron and chrome. All catch had levels of lead and cadmium, two toxic elements, below the maximum sanitary limits. Although some concerns were raised regarding mercury concentrations in the largest species (wahoo, swordfish and blue marlin), molar ratios of mercury and selenium indicate that all oceanic pelagic fish from the western-central Indian Ocean are safe for human consumption. This study also gives insights on the relationships between the levels of essential and toxic elements in fish muscle and the size, trophic position and diet sources of the studied pelagic species. (C) 2017 Elsevier Ltd. All rights reserved.  
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  Langue English Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 0045-6535 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2119  
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Auteur Massol, F.; Altermatt, F.; Gounand, I.; Gravel, D.; Leibold, M.A.; Mouquet, N. doi  openurl
  Titre How life-history traits affect ecosystem properties: effects of dispersal in meta-ecosystems Type Article scientifique
  Année 2017 Publication Revue Abrégée Oikos  
  Volume 126 Numéro 4 Pages 532-546  
  Mots-Clés colonization trade-off; ecological stoichiometry; interaction strengths; neutral metacommunities; pond metacommunities; predator-prey interactions; source-sink metacommunities; species-diversity; terrestrial food webs; theoretical framework  
  Résumé The concept of life-history traits and the study of these traits are the hallmark of population biology. Acknowledging their variability and evolution has allowed us to understand how species adapt in response to their environment. The same traits are also involved in how species alter ecosystems and shape their dynamics and functioning. Some theories, such as the metabolic theory of ecology, ecological stoichiometry or pace-of-life theory, already recognize this junction, but only do so in an implicitly non-spatial context. Meanwhile, for a decade now, it has been argued that ecosystem properties have to be understood at a larger scale using meta-ecosystem theory because source-sink dynamics, community assembly and ecosystem stability are all modified by spatial structure. Here, we argue that some ecosystem properties can be linked to a single life-history trait, dispersal, i.e. the tendency of organisms to live, compete and reproduce away from their birth place. By articulating recent theoretical and empirical studies linking ecosystem functioning and dynamics to species dispersal, we aim to highlight both the known connections between life-history traits and ecosystem properties and the unknown areas, which deserve further empirical and theoretical developments.  
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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 0030-1299 ISBN Médium  
  Région (up) Expédition Conférence  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2120  
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Auteur Mellon-Duval, C.; Harmelin-Vivien, M.; Metral, L.; Loizeau, V.; Mortreux, S.; Roos, D.; Fromentin, J.-M. doi  openurl
  Titre Trophic ecology of the European hake in the Gulf of Lions, northwestern Mediterranean Sea Type Article scientifique
  Année 2017 Publication Revue Abrégée Sci. Mar.  
  Volume 81 Numéro 1 Pages 7-18  
  Mots-Clés age; bay; biscay; celtic sea; diet; foodweb; glm; habitat; Merluccius merluccius; merluccius-merluccius l.; predator-prey relationships; Size; small pelagic fish; spatiotemporal variation; stable-isotope ratios; Stable isotopes; Stomach contents  
  Résumé 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 (delta N-15, delta C-13) analyses were performed, and the main factors explaining variations in delta N-15 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 showed that the size and diversity of prey vary among hake size classes, probably as a result of the different spatial distribution and/or foraging migrations. The present study finally postulates that the unbalanced sex ratio (80% female against 20% male) observed at the adult stage could be related to the combination of growth pattern differences, diet and exploitation rate on the continental shelf, where the males spend a longer period of time.  
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  Volume de collection Numéro de collection Edition  
  ISSN 0214-8358 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2121  
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Auteur Descombes, P.; Leprieur, F.; Albouy, C.; Heine, C.; Pellissier, L. doi  openurl
  Titre Spatial imprints of plate tectonics on extant richness of terrestrial vertebrates Type Article scientifique
  Année 2017 Publication Revue Abrégée J. Biogeogr.  
  Volume 44 Numéro 5 Pages 1185-1197  
  Mots-Clés american biotic interchange; amphibian; andean uplift; bird; climate-change; continental drift; diversification rates; diversity; global patterns; indo-pacific; large-scale patterns; madagascar; mammal; plate tectonics; sea-level; Southeast Asia; species richness; Wallace line; wallaces line  
  Résumé AimIn interaction with past climate changes, it is likely that plate tectonics contributed to the shaping of current global species diversity, but so far this has not been statistically quantified at the global level. Here, we tested whether plate tectonics since the breakup of Gondwana left an imprint on current patterns of species richness of amphibians, birds and mammals. LocationGlobal. MethodsWe reconstructed the absolute positions of continental plates since the Early Cretaceous and used this information to derive variables of latitudinal shifts and potential exchanges among landmasses that could have modulated species richness. Using a multi-model inference approach combining both contemporary and historical variables, we quantified the relative importance of variables related to plate tectonics in explaining the spatial variation of the richness of amphibians, birds and mammals. Next, we employed a moving window approach to test whether plate tectonics left a more marked imprint in specific regions. ResultsPlatetectonics left an imprint on current patterns of vertebrate species richness in geologically singular regions, especially in the Indo-Australian Archipelago and the region comprising eastern Africa and Madagascar. For birds and mammals, but not amphibians, we found a marked contrast in species richness across Australia and Southeast Asia and eastern Africa and Madagascar associated with plate tectonics. Moreover, the relationship between species richness and plate tectonics varied across taxonomic orders for birds and mammals. Main conclusionsWhile no general imprint of plate tectonics was detected at the global scale, our regional analysis highlighted a substantial role of geodynamics in shaping current patterns of vertebrate species richness in Southeast Asia and Madagascar. Future studies should integrate the full range of processes associated with plate tectonics, including orogeny, not considered here.  
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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 0305-0270 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2129  
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Auteur Authier, M.; Saraux, C.; Péron, C. doi  openurl
  Titre Variable selection and accurate predictions in habitat modelling: a shrinkage approach Type Article scientifique
  Année 2017 Publication Revue Abrégée Ecography  
  Volume 40 Numéro 4 Pages 549-560  
  Mots-Clés account; distributional data; Ecology; indian-ocean; inference; Mediterranean Sea; regression methods; small pelagic fish; spatial autocorrelation; species distribution models  
  Résumé Habitat modelling is increasingly relevant in biodiversity and conservation studies. A typical application is to predict potential zones of specific conservation interest. With many environmental covariates, a large number of models can he investigated but multi-model inference may become impractical. Shrinkage regression overcomes this issue by dealing with the identification and accurate estimation of effect size for prediction. In a Bayesian framework we investigated the use of a shrinkage prior, the Horseshoe, for variable selection in spatial generalized linear models (GLM). As study cases, we considered 5 datasets on small pelagic fish abundance in the Gulf of Lion (Mediterranean Sea, France) and 9 environmental inputs. We compared the predictive performances of a simple kriging model, a full spatial GLM model with independent normal priors for regression coefficients, a full spatial GLM model with a Horseshoe prior for regression coefficients and 2 zero-inflated models (spatial and non-spatial) with a Horseshoe prior. Predictive performances were evaluated by cross validation on a hold-out subset of the data: models with a Horseshoe prior performed best, and the full model with independent normal priors worst. With an increasing number of inputs, extrapolation quickly became pervasive as we tried to predict from novel combinations of covariate values. By shrinking regression coefficients with a Horseshoe prior, only one model needed to be fitted to the data in order to obtain reasonable and accurate predictions, including extrapolations.  
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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 0906-7590 ISBN Médium  
  Région (up) Expédition Conférence  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2130  
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