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Auteur Theuerkauff, D.; Rivera-Ingraham, G.A.; Roques, J.A.C.; Azzopardi, L.; Bertini, M.; Lejeune, M.; Farcy, E.; Lignot, J.-H.; Sucre, E. doi  openurl
  Titre Salinity Variation in a Mangrove Ecosystem: A Physiological Investigation to Assess Potential Consequences of Salinity Disturbances on Mangrove Crabs Type Article scientifique
  Année 2018 Publication Revue Abrégée Zool. Stud.  
  Volume (down) 57 Numéro Pages 36  
  Mots-Clés Bioenergetics; blue-crab; callinectes-sapidus; carcinus-maenas; Decapods; dilocarcinus-pagei brachyura; eriocheir-sinensis; fiddler-crabs; fresh-water; grapsid crabs; Mangrove; Osmoregulation; oxidative stress; Salinity-induced oxidative stress; waste-water treatment  
  Résumé Dimitri Theuerkauff, Georgina A. Rivera-Ingraham, Jonathan A.C. Roques, Laurence Azzopardi, Marine Bertini, Mathilde Lejeune, Emilie Farcy, Jehan-Herve Lignot, and Elliott Sucre (2018) Salinity is one of the main environmental factors determining coastal species distribution. However, in the specific case of mangrove crabs, salinity selection cannot be understood through ecological approaches alone. Yet understanding this issue is crucial in the context of mangrove conservation, since this ecosystem is often used as biofilter of (low-salinity) wastewater. Crabs are keystone species in this mangrove ecosystem and are differentially affected by salinity. We hypothesize that crab salinity selection may be partly explained by specific salinity-induced physiological constraints associated with osmoregulation, energy and redox homeostasis. To test this, the response to salinity variation was analysed in two landward mangrove crabs: the fiddler crab Tubuca urvillei, which inhabits low-salinity areas of the mangrove, and the red mangrove crab Neosarmatium meinerti, which lives in areas with higher salinity. Results confirm that both species are strong hypo-/hyper-osmoregulators that deal easily with large salinity variations. Such shifts in salinity do not induce changes in energy expenditure (measured as oxygen consumption) or in the production of reactive oxygen species. However, T. urvillei is physiologically suited to habitats with brackish water, since it presents i) high hemolymph osmolalities over a wider range of salinities and lower osmoregulatory capacity in seawater, ii) high Na+/K+-ATPase (NKA) activity in the posterior osmoregulatory gills and iii) a thicker osmoregulatory epithelium along the posterior gill lamellae. Therefore, while environmental salinity alone cannot directly explain fiddler and red mangrove crab distributions, our data suggest that salinity selection is indeed influenced by specific physiological adjustments.  
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  ISSN 1021-5506 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2424  
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Auteur Leitao, R.P.; Zuanon, J.; Mouillot, D.; Leal, C.G.; Hughes, R.M.; Kaufmann, P.R.; Villeger, S.; Pompeu, P.S.; Kasper, D.; de Paula, F.R.; Ferraz, S.F.B.; Gardner, T.A. doi  openurl
  Titre Disentangling the pathways of land use impacts on the functional structure of fish assemblages in Amazon streams Type Article scientifique
  Année 2018 Publication Revue Abrégée Ecography  
  Volume (down) 41 Numéro 1 Pages 219-232  
  Mots-Clés biodiversity; diversity; responses; habitat; community structure; fresh-water fish; aquatic vertebrates; deforestation; ecosystem processes; multiple spatial scales  
  Résumé Agricultural land use is a primary driver of environmental impacts on streams. However, the causal processes that shape these impacts operate through multiple pathways and at several spatial scales. This complexity undermines the development of more effective management approaches, and illustrates the need for more in-depth studies to assess the mechanisms that determine changes in stream biodiversity. Here we present results of the most comprehensive multi-scale assessment of the biological condition of streams in the Amazon to date, examining functional responses of fish assemblages to land use. We sampled fish assemblages from two large human-modified regions, and characterized stream conditions by physical habitat attributes and key landscape-change variables, including density of road crossings (i.e. riverscape fragmentation), deforestation, and agricultural intensification. Fish species were functionally characterized using ecomorphological traits describing feeding, locomotion, and habitat preferences, and these traits were used to derive indices that quantitatively describe the functional structure of the assemblages. Using structural equation modeling, we disentangled multiple drivers operating at different spatial scales, identifying causal pathways that significantly affect stream condition and the structure of the fish assemblages. Deforestation at catchment and riparian network scales altered the channel morphology and the stream bottom structure, changing the functional identity of assemblages. Local deforestation reduced the functional evenness of assemblages (i.e. increased dominance of specific trait combinations) mediated by expansion of aquatic vegetation cover. Riverscape fragmentation reduced functional richness, evenness and divergence, suggesting a trend toward functional homogenization and a reduced range of ecological niches within assemblages following the loss of regional connectivity. These results underscore the often-unrecognized importance of different land use changes, each of which can have marked effects on stream biodiversity. We draw on the relationships observed herein to suggest priorities for the improved management of stream systems in the multiple-use landscapes that predominate in human-modified tropical forests.  
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  ISSN 0906-7590 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2252  
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Auteur Compte-Port, S.; Borrego, C.M.; Moussard, H.; Jeanbille, M.; Restrepo-Ortiz, C.X.; de Diego, A.; Rodriguez-Iruretagoiena, A.; Gredilla, A.; Fdez-Ortiz de Vallejuelo, S.; Galand, P.E.; Kalenitchenko, D.; Rols, J.-L.; Pokrovsky, O.S.; Gonzalez, A.G.; Camarero, L.; Muniz, S.; Navarro-Navarro, E.; Auguet, J.-C. doi  openurl
  Titre Metal contaminations impact archaeal community composition, abundance and function in remote alpine lakes Type Article scientifique
  Année 2018 Publication Revue Abrégée Environ. Microbiol.  
  Volume (down) 20 Numéro 7 Pages 2422-2437  
  Mots-Clés ammonia-oxidizing archaea; fresh-water lakes; high-altitude lakes; high-mountain lakes; mcra gene; methanogenic archaea; microbial communities; ribosomal-rna; tibetan plateau; trace-metals  
  Résumé Using the 16S rRNA and mcrA genes, we investigated the composition, abundance and activity of sediment archaeal communities within 18 high-mountain lakes under contrasted metal levels from different origins (bedrock erosion, past-mining activities and atmospheric depositions). Bathyarchaeota, Euryarchaeota and Woesearchaeota were the major phyla found at the meta-community scale, representing 48%, 18.3% and 15.2% of the archaeal community respectively. Metals were equally important as physicochemical variables in explaining the assemblage of archaeal communities and their abundance. Methanogenesis appeared as a process of central importance in the carbon cycle within sediments of alpine lakes as indicated by the absolute abundance of methanogen 16S rRNA and mcrA gene transcripts (10(5) to 10(9) copies g(-1)). We showed that methanogen abundance and activity were significantly reduced with increasing concentrations of Pb and Cd, two indicators of airborne metal contaminations. Considering the ecological importance of methanogenesis in sediment habitats, these metal contaminations may have system wide implications even in remote area such as alpine lakes. Overall, this work was pioneer in integrating the effect of long-range atmospheric depositions on archaeal communities and indicated that metal contamination might significantly compromise the contribution of Archaea to the carbon cycling of the mountain lake sediments.  
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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 1462-2912 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2420  
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Auteur Buisson, L.; Grenouillet, G.; Villeger, S.; Canal, J.; Laffaille, P. url  doi
openurl 
  Titre Toward a loss of functional diversity in stream fish assemblages under climate change Type Article scientifique
  Année 2013 Publication Revue Abrégée Glob. Change Biol.  
  Volume (down) 19 Numéro 2 Pages 387-400  
  Mots-Clés assemblages; biotic homogenization; bird communities; climate change; distribution models; ecosystem; environmental-change; fresh-water biodiversity; functional traits; habitat; no-analog communities; range shifts; species; species distribution; stream fish; traits  
  Résumé The assessment of climate change impacts on biodiversity has so far been biased toward the taxonomic identification of the species likely either to benefit from climate modifications or to experience overall declines. There have still been few studies intended to correlate the characteristics of species to their sensitivity to climate change, even though it is now recognized that functional trait-based approaches are promising tools for addressing challenges related to global changes. In this study, two functional indices (originality and uniqueness) were first measured for 35 fish species occurring in French streams. They were then combined to projections of range shifts in response to climate change derived from species distribution models. We set out to investigate: (1) the relationship between the degrees of originality and uniqueness of fish species, and their projected response to future climate change; and (2) the consequences of individual responses of species for the functional diversity of fish assemblages. After accounting for phylogenetic relatedness among species, we have demonstrated that the two indices used measure two complementary facets of the position of fish species in a functional space. We have also rejected the hypothesis that the most original and/or less redundant species would necessarily experience the greatest declines in habitat suitability as a result of climate change. However, individual species range shifts could lead simultaneously both to a severe decline in the functional diversity of fish assemblages, and to an increase in the functional similarity among assemblages, supporting the hypothesis that disturbance favors communities with combination of common traits and biotic homogenization as well. Our findings therefore emphasize the importance of going beyond the simple taxonomic description of diversity to provide a better assessment of the likely future effects of environmental changes on biodiversity, thus helping to design more effective conservation and management measures.  
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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 1354-1013 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 897  
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Auteur Panfili, J.; Darnaude, A.M.; Lin, Y.J.; Chevalley, M.; Iizuka, Y.; Tzeng, W.N.; Crivelli, A.J. url  doi
openurl 
  Titre Habitat residence during continental life of the European eel Anguilla anguilla investigated using linear discriminant analysis applied to otolith Sr:Ca ratios Type Article scientifique
  Année 2012 Publication Revue Abrégée Aquat. Biol.  
  Volume (down) 15 Numéro 2 Pages 175-185  
  Mots-Clés Anguilla anguilla; Epma; European eel; La-Icpms; Mediterranean area; Otolith; Strontium:calcium ratio; coastal; elemental fingerprints; estuarine; fish otoliths; fresh-water environments; history; japonica; mass; microchemistry; rostrata; spectrometry; sr-ca ratios  
  Résumé European eel Anguilla anguilla migratory behaviour during continental life is still unclear due to the multiplicity of aquatic environments colonised by the species. In the Camargue area (NW Mediterranean), eel colonisation of the Fumemorte canal, a freshwater habitat that communicates only with a vast brackish ecosystem (the Vaccares lagoon), offers a rare opportunity to test for freshwater habitat residence during continental life. To this end, both laser ablation inductively coupled plasma mass spectrometry and electron probe micro-analysis were used to measure chronological variations of strontium concentrations (Sr:Ca) in the otoliths of 58 silver eels captured in the canal between 1997 and 2007. Comparing mean Sr: Ca ratios measured on otolith edges with the 2 analytical methods indicated that they provide comparable measurement accuracies. Linear discriminant analysis (LDA), based on the otolith Sr: Ca values corresponding to the initial entrance of the fish into the brackish ecosystem and their final capture in the freshwater canal, allowed successful discrimination of the 2 habitats and reconstruction of migratory history for all individuals. Six different migratory behaviours were identified. Eels that entered the freshwater canal did so either directly (67%) or after 1 to 2 yr spent in the lagoon (33%), with a subsequent majority of freshwater residents (55%) until their silvering. These results indicate the value of LDA for reconstructing habitat use during continental life using Sr: Ca ratios. They confirm the occurrence of freshwater residence during continental life in European eels, even in Mediterranean continental areas where brackish environments are predominant. This observed sedentary behaviour has implications for eel population management and conservation.  
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  ISSN 1864-7790 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 626  
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