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Auteur Mostajir, B.; Amblard, C.; Buffan-Dubau, E.; De Wit, R.; Lensi, R.; Sime-Ngando, T. url  isbn
openurl 
  Titre Microbial Food Webs in Aquatic and Terrestrial Ecosystems Type Chapitre de livre
  Année 2015 Publication Revue Abrégée  
  Volume Numéro Pages 485-509  
  Mots-Clés (up) Biodiversity; Biogeochemical cycles; Ecological interactions; Microbial Ecology; Microbial food webs; Microbial loop  
  Résumé In microbial food webs, different types of interactions occur between microorganisms themselves and with meio- and macroorganisms. After an historical and general introduction, the biological components of the microbial food webs in the pelagic and benthic marine and lake ecosystems, as well as in the terrestrial ecosystems, are presented. The functioning of the microbial food webs in different ecosystems is illustrated and explained, including the trophic pathways and transfer of matter from microbial food webs toward meio- and macroorganisms of the superior trophic levels, the nutrient recycling in the aquatic environments, and the decomposition of organic matter in soils. Finally, the factors regulating microbial food webs, primarily “top-down” and “bottom-up” controls, are described with a special focus on the role of viruses in the aquatic microbial food webs.  
  Adresse  
  Auteur institutionnel Thèse  
  Editeur Springer Netherlands Lieu de Publication Éditeur Bertrand, J.-C.; Caumette, P.; Lebaron, P.; Matheron, R.; Normand, P.; Sime-Ngando, T.  
  Langue en Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé Environmental Microbiology: Fundamentals and Applications  
  Volume de collection Numéro de collection Edition  
  ISSN ISBN 978-94-017-9117-5 978-94-017-9118-2 Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 1394  
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Auteur Jacquet, C.; Moritz, C.; Morissette, L.; Legagneux, P.; Massol, F.; Archambault, P.; Gravel, D. doi  openurl
  Titre No complexity-stability relationship in empirical ecosystems Type Article scientifique
  Année 2016 Publication Revue Abrégée Nat. Commun.  
  Volume 7 Numéro Pages 12573  
  Mots-Clés (up) biodiversity; body-size; connectance; diversity; ecopath; interaction strengths; models; perturbations; real food webs; systems  
  Résumé Understanding the mechanisms responsible for stability and persistence of ecosystems is one of the greatest challenges in ecology. Robert May showed that, contrary to intuition, complex randomly built ecosystems are less likely to be stable than simpler ones. Few attempts have been tried to test May's prediction empirically, and we still ignore what is the actual complexity-stability relationship in natural ecosystems. Here we perform a stability analysis of 116 quantitative food webs sampled worldwide. We find that classic descriptors of complexity (species richness, connectance and interaction strength) are not associated with stability in empirical food webs. Further analysis reveals that a correlation between the effects of predators on prey and those of prey on predators, combined with a high frequency of weak interactions, stabilize food web dynamics relative to the random expectation. We conclude that empirical food webs have several non-random properties contributing to the absence of a complexity-stability relationship.  
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  Auteur institutionnel Thèse  
  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 2041-1723 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 1638  
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Auteur Cazelles, K.; Mouquet, N.; Mouillot, D.; Gravel, D. doi  openurl
  Titre On the integration of biotic interaction and environmental constraints at the biogeographical scale Type Article scientifique
  Année 2016 Publication Revue Abrégée Ecography  
  Volume 39 Numéro 10 Pages 921-931  
  Mots-Clés (up) biodiversity; climate-change; cooccurrence; distributions; ecological communities; evolutionary; food webs; networks; niche; species distribution models  
  Résumé Biogeography is primarily concerned with the spatial distribution of biodiversity, including performing scenarios in a changing environment. The efforts deployed to develop species distribution models have resulted in predictive tools, but have mostly remained correlative and have largely ignored biotic interactions. Here we build upon the theory of island biogeography as a first approximation to the assembly dynamics of local communities embedded within a metacommunity context. We include all types of interactions and introduce environmental constraints on colonization and extinction dynamics. We develop a probabilistic framework based on Markov chains and derive probabilities for the realization of species assemblages, rather than single species occurrences. We consider the expected distribution of species richness under different types of ecological interactions. We also illustrate the potential of our framework by studying the interplay between different ecological requirements, interactions and the distribution of biodiversity along an environmental gradient. Our framework supports the idea that the future research in biogeography requires a coherent integration of several ecological concepts into a single theory in order to perform conceptual and methodological innovations, such as the switch from single-species distribution to community distribution.  
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  Auteur institutionnel Thèse  
  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 0906-7590 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 1683  
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Auteur Duffy, L.M.; Kuhnert, P.; Pethybridge, H.R.; Young, J.W.; Olson, R.J.; Logan, J.M.; Goñi, N.; Romanov, E.; Allain, V.; Staudinger, M.; Abecassis, M.; Choy, C.A.; Hobday, A.J.; Simier, M.; Galván-Magaña, F.; Potier, M.; Ménard, F. url  doi
openurl 
  Titre Global trophic ecology of yellowfin, bigeye, and albacore tunas: understanding predation on micronekton communities at ocean-basin scales Type Article scientifique
  Année 2017 Publication Revue Abrégée Deep Sea Research Part II: Topical Studies in Oceanography  
  Volume 140 Numéro Pages 55-73  
  Mots-Clés (up) classification trees; climate changes; ecosystems; food webs; inter-ocean comparison; macroecology; Meta-analysis; trophic relationships  
  Résumé Predator-prey interactions for three commercially valuable tuna species: yellowfin (Thunnus albacares), bigeye (T. obesus), and albacore (T. alalunga), collected over a 40-year period from the Pacific, Indian, and Atlantic Oceans, were used to quantitatively assess broad, macro-scale trophic patterns in pelagic ecosystems. Analysis of over 14,000 tuna stomachs, using a modified classification tree approach, revealed for the first time the global expanse of pelagic predatory fish diet and global patterns of micronekton diversity. Ommastrephid squids were consistently one of the top prey groups by weight across all tuna species and in most ocean bodies. Interspecific differences in prey were apparent, with epipelagic scombrid and mesopelagic paralepidid fishes globally important for yellowfin and bigeye tunas, respectively, while vertically-migrating euphausiid crustaceans were important for albacore tuna in the Atlantic and Pacific Oceans. Diet diversity showed global and regional patterns among tuna species. In the central and western Pacific Ocean, characterized by low productivity, a high diversity of micronekton prey was consumed while low prey diversity was evident in highly productive coastal waters where upwelling occurs. Spatial patterns of diet diversity were most variable in yellowfin and bigeye tunas while a latitudinal diversity gradient was observed with lower diversity in temperate regions for albacore tuna. Sea-surface temperature was a reasonable predictor of the diets of yellowfin and bigeye tunas, whereas chlorophyll-a was the best environmental predictor of albacore diet. These results suggest that the ongoing expansion of warmer, less productive waters in the world’s oceans may alter foraging opportunities for tunas due to regional changes in prey abundances and compositions.  
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  Auteur institutionnel Thèse  
  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 0967-0645 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 2102  
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Auteur Lotze, H.K.; Tittensor, D.P.; Bryndum-Buchholz, A.; Eddy, T.D.; Cheung, W.W.L.; Galbraith, E.D.; Barange, M.; Barrier, N.; Bianchi, D.; Blanchard, J.L.; Bopp, L.; Büchner, M.; Bulman, C.M.; Carozza, D.A.; Christensen, V.; Coll, M.; Dunne, J.P.; Fulton, E.A.; Jennings, S.; Jones, M.C.; Mackinson, S.; Maury, O.; Niiranen, S.; Oliveros-Ramos, R.; Roy, T.; Fernandes, J.A.; Schewe, J.; Shin, Y.-J.; Silva, T.A.M.; Steenbeek, J.; Stock, C.A.; Verley, P.; Volkholz, J.; Walker, N.D.; Worm, B. url  doi
openurl 
  Titre Global ensemble projections reveal trophic amplification of ocean biomass declines with climate change Type Article scientifique
  Année 2019 Publication Revue Abrégée Pnas  
  Volume 116 Numéro 26 Pages 12907-12912  
  Mots-Clés (up) climate change impacts; global ecosystem modeling; marine food webs; model intercomparison; uncertainty  
  Résumé While the physical dimensions of climate change are now routinely assessed through multimodel intercomparisons, projected impacts on the global ocean ecosystem generally rely on individual models with a specific set of assumptions. To address these single-model limitations, we present standardized ensemble projections from six global marine ecosystem models forced with two Earth system models and four emission scenarios with and without fishing. We derive average biomass trends and associated uncertainties across the marine food web. Without fishing, mean global animal biomass decreased by 5% (±4% SD) under low emissions and 17% (±11% SD) under high emissions by 2100, with an average 5% decline for every 1 °C of warming. Projected biomass declines were primarily driven by increasing temperature and decreasing primary production, and were more pronounced at higher trophic levels, a process known as trophic amplification. Fishing did not substantially alter the effects of climate change. Considerable regional variation featured strong biomass increases at high latitudes and decreases at middle to low latitudes, with good model agreement on the direction of change but variable magnitude. Uncertainties due to variations in marine ecosystem and Earth system models were similar. Ensemble projections performed well compared with empirical data, emphasizing the benefits of multimodel inference to project future outcomes. Our results indicate that global ocean animal biomass consistently declines with climate change, and that these impacts are amplified at higher trophic levels. Next steps for model development include dynamic scenarios of fishing, cumulative human impacts, and the effects of management measures on future ocean biomass trends.  
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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 0027-8424, 1091-6490 ISBN Médium  
  Région Expédition Conférence  
  Notes WOS:000472719100059 Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2586  
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