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Auteur Albo-Puigserver, M.; Navarro, J.; Coll, M.; Layman, C.A.; Palomera, I. doi  openurl
  Titre Trophic structure of pelagic species in the northwestern Mediterranean Sea Type Article scientifique
  Année 2016 Publication Revue Abrégée J. Appl. Dev. Psychol.  
  Volume (down) 47 Numéro Pages 27-35  
  Mots-Clés anchovy engraulis-encrasicolus; biscay northeast atlantic; Community structure; diet composition; food-web; Food web; hake merluccius-merluccius; horse mackerel; Isotopic niche; mackerel scomber-japonicus; Pelagic fish; sardine sardina-pilchardus; Seasonal; seasonal-changes; Stable isotopes; stable-isotopes; Trophic segregation  
  Résumé Ecological knowledge of food web interactions within pelagic marine communities is often limited, impairing our capabilities to manage these ecologically and economically important marine fish species. Here we used stable isotope analyses to investigate trophic interactions in the pelagic ecosystem of the northwestern Mediterranean Sea during 2012 and 2013. Our results suggest that European sardine, Sardina pilchardus, and anchovy, Engraulis encrasicolus, are consumers located at relatively low levels of the pelagic food web. Unexpectedly, the round sardinella, Sardinella aurita, appeared to be located at a higher trophic level than the other small pelagic fish species, although previous studies found similarity in their diets. Isotope data suggested that trophic niches of species within the genera Trachurus spp. and Scomber spp., were distinct. Atlantic bonito Sarda sarda, European hake Merluccius merluccius and European squid Loligo vulgaris, appeared to feed at higher trophic levels than other species. Despite some intraspecific seasonal variability for some species, community trophic structure appeared relatively stable through the year. These data provide an important step for developing models of food web dynamics in the northwestern Mediterranean Sea. (C) 2016 Elsevier B.V. All rights reserved.  
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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 0193-3973 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 1691  
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Auteur Albouy, C.; Velez, L.; Coll, M.; Colloca, F.; Le Loc'h, F.; Mouillot, D.; Gravel, D. url  doi
openurl 
  Titre From projected species distribution to food-web structure under climate change Type Article scientifique
  Année 2014 Publication Revue Abrégée Global Change Biology  
  Volume (down) 20 Numéro 3 Pages 730-741  
  Mots-Clés climate change; connectance; fish body size; food-webs; generality; Mediterranean Sea; metaweb; niche model; vulnerability  
  Résumé  
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  Editeur Lieu de Publication Éditeur  
  Langue Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 1354-1013 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel LL @ pixluser @ collection 324  
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Auteur Sebastian, M.; Smith, A.F.; Gonzalez, J.M.; Fredricks, H.F.; Van Mooy, B.; Koblizek, M.; Brandsma, J.; Koster, G.; Mestre, M.; Mostajir, B.; Pitta, P.; Postle, A.D.; Sanchez, P.; Gasol, J.M.; Scanlan, D.J.; Chen, Y. doi  openurl
  Titre Lipid remodelling is a widespread strategy in marine heterotrophic bacteria upon phosphorus deficiency Type Article scientifique
  Année 2016 Publication Revue Abrégée Isme J.  
  Volume (down) 10 Numéro 4 Pages 968-978  
  Mots-Clés 2 enzymes; agrobacterium-tumefaciens; bacterioplankton groups; Ecology; Mediterranean Sea; mesocosm experiment; microbial food-web; north-atlantic ocean; nutrient limitation; phosphate starvation  
  Résumé Upon phosphorus (P) deficiency, marine phytoplankton reduce their requirements for P by replacing membrane phospholipids with alternative non-phosphorus lipids. It was very recently demonstrated that a SAR11 isolate also shares this capability when phosphate starved in culture. Yet, the extent to which this process occurs in other marine heterotrophic bacteria and in the natural environment is unknown. Here, we demonstrate that the substitution of membrane phospholipids for a variety of non-phosphorus lipids is a conserved response to P deficiency among phylogenetically diverse marine heterotrophic bacteria, including members of the Alphaproteobacteria and Flavobacteria. By deletion mutagenesis and complementation in the model marine bacterium Phaeobacter sp. MED193 and heterologous expression in recombinant Escherichia coli, we confirm the roles of a phospholipase C (PlcP) and a glycosyltransferase in lipid remodelling. Analyses of the Global Ocean Sampling and Tara Oceans metagenome data sets demonstrate that PlcP is particularly abundant in areas characterized by low phosphate concentrations. Furthermore, we show that lipid remodelling occurs seasonally and responds to changing nutrient conditions in natural microbial communities from the Mediterranean Sea. Together, our results point to the key role of lipid substitution as an adaptive strategy enabling heterotrophic bacteria to thrive in the vast P-depleted areas of the ocean.  
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  Langue English Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 1751-7362 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 1624  
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Auteur Galiana, N.; Lurgi, M.; Claramunt-Lopez, B.; Fortin, M.-J.; Leroux, S.; Cazelles, K.; Gravel, D.; Montoya, J.M. doi  openurl
  Titre The spatial scaling of species interaction networks Type Article scientifique
  Année 2018 Publication Revue Abrégée Nat. Ecol. Evol.  
  Volume (down) 2 Numéro 5 Pages 782-790  
  Mots-Clés area relationships; biodiversity; competition; diversity; ecological networks; extinction; food-web structure; habitat loss; source-sink metacommunities; trophic interactions  
  Résumé Species-area relationships (SARs) are pivotal to understand the distribution of biodiversity across spatial scales. We know little, however, about how the network of biotic interactions in which biodiversity is embedded changes with spatial extent. Here we develop a new theoretical framework that enables us to explore how different assembly mechanisms and theoretical models affect multiple properties of ecological networks across space. We present a number of testable predictions on network-area relationships (NARs) for multi-trophic communities. Network structure changes as area increases because of the existence of different SARs across trophic levels, the preferential selection of generalist species at small spatial extents and the effect of dispersal limitation promoting beta-diversity. Developing an understanding of NARs will complement the growing body of knowledge on SARs with potential applications in conservation ecology. Specifically, combined with further empirical evidence, NARs can generate predictions of potential effects on ecological communities of habitat loss and fragmentation in a changing world.  
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  Langue English Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 2397-334x ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2339  
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Auteur Meddeb, M.; Grami, B.; Chaalali, A.; Haraldsson, M.; Niquil, N.; Pringault, O.; Sakka Hlaili, A. url  doi
openurl 
  Titre Plankton food-web functioning in anthropogenically impacted coastal waters (SW Mediterranean Sea): an ecological network analysis Type Article scientifique
  Année 2018 Publication Revue Abrégée Progress in Oceanography  
  Volume (down) Numéro Pages  
  Mots-Clés Ecological Network Analysis; Food-web modelling; Mediterranean coastal waters; plankton ecology  
  Résumé The study is the first attempt to (i) model spring food webs in three SW Mediterranean ecosystems which are under different anthropogenic pressures and (ii) to project the consequence of this stress on their function. Linear inverse models were built using the Monte Carlo method coupled with Markov Chains to characterize the food-web status of the Lagoon, the Channel (inshore waters under high eutrophication and chemical contamination) and the Bay of Bizerte (offshore waters under less anthropogenic pressure). Ecological network analysis was used for the description of structural and functional properties of each food web and for inter-ecosystem comparisons. Our results showed that more carbon was produced by phytoplankton in the inshore waters (966–1234 mg C m-2 d-1) compared to the Bay (727 mg C m-2 d-1). The total ecosystem carbon inputs into the three food webs was supported by high primary production, which was mainly due to >10µm algae. However, the three carbon pathways were characterized by low detritivory and a high herbivory which was mainly assigned to protozooplankton. This latter was efficient in channelling biogenic carbon. In the Lagoon and the Channel, foods webs acted almost as a multivorous structure with a tendency towards herbivorous one, whereas in the Bay the herbivorous pathway was more dominant. Ecological indices revealed that the Lagoon and the Channel food webs/systems had high total system throughput and thus were more active than the Bay. The Bay food web, which had a high relative ascendency value, was more organized and specialized. This inter–ecosystem difference could be due to the varying levels of anthropogenic impact among sites. Indeed, the low value of Finn’s cycling index indicated that the three systems are disturbed, but the Lagoon and the Channel, with low average path lengths, appeared to be more stressed, as both sites have undergone higher chemical pollution and nutrient loading. This study shows that ecosystem models combined with ecological indices provide a powerful approach to detect change in environmental status and anthropogenic impacts.  
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  Volume de collection Numéro de collection Edition  
  ISSN 0079-6611 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2292  
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