bascule de visibilité Search & Display Options

Tout Sélectionner    Désélectionner
 |   | 
Détails
   print
  Enregistrements Liens
Auteur (up) 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 20 Numéro 3 Pages 730-741  
  Mots-Clés climate change; connectance; fish body size; food-webs; generality; Mediterranean Sea; metaweb; niche model; vulnerability  
  Résumé  
  Adresse  
  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 1354-1013 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel LL @ pixluser @ collection 324  
Lien permanent pour cet enregistrement
 

 
Auteur (up) Amelineau, F.; Bonnet, D.; Heitz, O.; Mortreux, V.; Harding, A.M.A.; Karnovsky, N.; Walkusz, W.; Fort, J.; Gremillet, D. doi  openurl
  Titre Microplastic pollution in the Greenland Sea: Background levels and selective contamination of planktivorous diving seabirds Type Article scientifique
  Année 2016 Publication Revue Abrégée Environ. Pollut.  
  Volume 219 Numéro Pages 1131-1139  
  Mots-Clés accumulation; Arctic; dovekies alle-alle; identification; ingestion; Little auk; marine debris; north-atlantic; pacific; Plastic; plastic-derived chemicals; Sea ice; Selective uptake; Size; vertical-distribution; Zooplankton  
  Résumé Microplastics have been reported everywhere around the globe. With very limited human activities, the Arctic is distant from major sources of microplastics. However, microplastic ingestions have been found in several Arctic marine predators, confirming their presence in this region. Nonetheless, existing information for this area remains scarce, thus there is an urgent need to quantify the contamination of Arctic marine waters. In this context, we studied microplastic abundance and composition within the zooplankton community off East Greenland. For the same area, we concurrently evaluated microplastic contamination of little auks (Alle alle), an Arctic seabird feeding on zooplankton while diving between 0 and 50 m. The study took place off East Greenland in July 2005 and 2014, under strongly contrasted sea-ice conditions. Among all samples, 97.2% of the debris found were filaments. Despite the remoteness of our study area, microplastic abundances were comparable to those of other oceans, with 0.99 +/- 0.62 m(-3) in the presence of sea-ice (2005), and 2.38 +/- 1.11 m(-3) in the nearby absence of sea-ice (2014). Microplastic rise between 2005 and 2014 might be linked to an increase in plastic production worldwide or to lower sea -ice extents in 2014, as sea-ice can represent a sink for microplastic particles, which are subsequently released to the water column upon melting. Crucially, all birds had eaten plastic filaments, and they collected high levels of microplastics compared to background levels with 9.99 and 8.99 pieces per chick meal in 2005 and 2014, respectively. Importantly, we also demonstrated that little auks took more often light colored microplastics, rather than darker ones, strongly suggesting an active contamination with birds mistaking microplastics for their natural prey. Overall, our study stresses the great vulnerability of Arctic marine species to microplastic pollution in a warming Arctic, where sea-ice melting is expected to release vast volumes of trapped debris. (C) 2016 Elsevier Ltd. All rights reserved.  
  Adresse  
  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 0269-7491 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ alain.herve @ collection 1716  
Lien permanent pour cet enregistrement
 

 
Auteur (up) Ayon, P.; Swartzman, G.; Espinoza, P.; Bertrand, A. url  doi
openurl 
  Titre Long-term changes in zooplankton size distribution in the Peruvian Humboldt Current System : conditions favouring sardine or anchovy Type Article scientifique
  Année 2011 Publication Revue Abrégée Marine Ecology. Progress Series  
  Volume 422 Numéro Pages 211-222  
  Mots-Clés abundance; anchovy; Current; dominance; energetics; Euphausiids; Feeding; Humboldt; Sardine; size; System; Zooplankton  
  Résumé Changes in the size distribution of zooplankton in the Humboldt Current System have been hypothesized to underlie observed changes in sardine and anchovy populations, the dominant pelagic fish species. To examine this hypothesis, the size distribution of over 15 000 zooplankton data samples collected since the 1960s was qualitatively determined. Dominance of each size group of zooplankton (small, medium and large) and of euphausiids was modelled using generalized additive models as a function of year, latitude, time of day, distance from the 200 m isobath (a surrogate for on-shelf versus off-shelf), sea surface temperature and salinity. The temporal (yr) pattern for euphausiid dominance was highly cross-correlated (i.e. was in phase) with the time series for estimated biomass of anchovy, and small zooplankton dominance with that for estimated sardine biomass. This supports the focal hypothesis based on feeding-energetic experiments, which showed energetic advantages to sardine filter feeding on smaller zooplankton and to anchovy bite feeding on larger copepods and euphausiids. Although euphausiids predominate offshore from the shelf break, anchovy biomass is generally highest on the shelf, suggesting a possible mismatch between anchovy feeding and euphausiid dominance. However, evidence concerning the offshore expansion of the anchovy range in cooler conditions, where both anchovy and euphausiids predominate, somewhat alleviates this apparent contradiction. A strong diel component to euphausiids and large zooplankton indicated diel migration for these zooplankton groups. That anchovy will preferentially eat euphausiids when they are more available (i.e. during the night and offshore) is supported by anchovy diet data.  
  Adresse  
  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 0171-8630 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel LL @ pixluser @ collection 117  
Lien permanent pour cet enregistrement
 

 
Auteur (up) Barneche, D.R.; Rezende, E.L.; Parravicini, V.; Maire, Eva; Edgar, G.J.; Stuart-Smith, R.D.; Arias-Gonzalez, J.E.; Ferreira, C.E.L.; Friedlander, A.M.; Green, A.L.; Luiz, O.J.; Rodriguez-Zaragoza, F.A.; Vigliola, L.; Kulbicki, M.; Floeter, S.R. doi  openurl
  Titre Body size, reef area and temperature predict global reef-fish species richness across spatial scales Type Article scientifique
  Année 2019 Publication Revue Abrégée Glob. Ecol. Biogeogr.  
  Volume 28 Numéro 3 Pages 315-327  
  Mots-Clés biodiversity; diversity; patterns; coral-reefs; spatial scale; community assembly; biogeography; extrapolation; local diversity; neutral theory; range size; rarefaction; regional diversity; species energy  
  Résumé Aim To investigate biotic and abiotic correlates of reef-fish species richness across multiple spatial scales. Location Tropical reefs around the globe, including 485 sites in 109 sub-provinces spread across 14 biogeographic provinces. Time period Present. Major taxa studied 2,523 species of reef fish. Methods We compiled a database encompassing 13,050 visual transects. We used hierarchical linear Bayesian models to investigate whether fish body size, reef area, isolation, temperature, and anthropogenic impacts correlate with reef-fish species richness at each spatial scale (i.e., sites, sub-provinces, provinces). Richness was estimated using coverage-based rarefaction. We also tested whether species packing (i.e., transect-level species richness/m(2)) is correlated with province-level richness. Results Body size had the strongest effect on species richness across all three spatial scales. Reef area and temperature were both positively correlated with richness at all spatial scales. At the site scale only, richness decreased with reef isolation. Species richness was not correlated with proxies of human impacts. Species packing was correlated with species richness at the province level following a sub-linear power function. Province-level differences in species richness were also mirrored by patterns of body size distribution at the site scale. Species-rich provinces exhibited heterogeneous assemblages of small-bodied species with small range sizes, whereas species-poor provinces encompassed homogeneous assemblages composed by larger species with greater dispersal capacity. Main conclusions Our findings suggest that body size distribution, reef area and temperature are major predictors of species richness and accumulation across scales, consistent with recent theories linking home range to species-area relationships as well as metabolic effects on speciation rates. Based on our results, we hypothesize that in less diverse areas, species are larger and likely more dispersive, leading to larger range sizes and less turnover between sites. Our results indicate that changes in province-level (i.e., regional) richness should leave a tractable fingerprint in local assemblages, and that detailed studies on local-scale assemblage composition may be informative of responses occurring at larger scales.  
  Adresse  
  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 1466-822x ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2522  
Lien permanent pour cet enregistrement
 

 
Auteur (up) Ben Othman, H.; Leboulanger, C.; Le Floc'h, E.; Mabrouk, H.H.; Hlaili, A.S. url  doi
openurl 
  Titre Toxicity of benz(a)anthracene and fluoranthene to marine phytoplankton in culture: Does cell size really matter? Type Article scientifique
  Année 2012 Publication Revue Abrégée J. Hazard. Mater.  
  Volume 243 Numéro Pages 204-211  
  Mots-Clés Benz(a)anthracene; Ecotoxicity; Fluoranthene; Size-sensitivity relationship; aquatic organisms; biodegradation; chlorophyll; fluorescence; food-web; fresh-water phytoplankton; in-vitro; organic pollutants; pahs; phytoplankton; polycyclic aromatic-hydrocarbons; surface sediments  
  Résumé The toxicity of benz(a)anthracene and fluoranthene (polycyclic aromatic hydrocarbons, PAHs) was evaluated on seven species of marine algae in culture belonging to pico-, nano-, and microphytoplankton, exposed to increasing concentrations of up to 2 mg L-1. The short-term (24 h) toxicity was assessed using chlorophyll a fluorescence transients, linked to photosynthetic parameters. The maximum quantum yield Fv/Fm was lower at the highest concentrations tested and the toxicity thresholds were species-dependent. For acute effects, fluoranthene was more toxic than benz(a)anthracene, with LOECs of 50.6 and 186 mu g L-1, respectively. After 72 h exposure, there was a dose-dependent decrease in cell density, fluoranthene being more toxic than benz(a)anthracene. The population endpoint at 72 h was affected to a greater extent than the photosynthetic endpoint at 24 h. EC50 was evaluated using the Hill model, and species sensitivity was negatively correlated to cell biovolume. The largest species tested, the dinoflagellate Alexandrium catenella, was almost insensitive to either PAH. The population endpoint EC50s for fluoranthene varied from 54 mu g L-1 for the picophytoplankton Picochlorum sp. to 418 mu g L-1 for the larger diatom Chaetoceros muelleri. The size/sensitivity relationship is proposed as a useful model when there is a lack of ecotoxicological data on hazardous chemicals, especially in marine microorganisms. (C) 2012 Elsevier B.V. All rights reserved.  
  Adresse  
  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 0304-3894 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 915  
Lien permanent pour cet enregistrement
Tout Sélectionner    Désélectionner
 |   | 
Détails
   print

Save Citations:
Export Records: