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Auteur Mazel, F.; Renaud, J.; Guilhaumon, F.; Mouillot, D.; Gravel, D.; Thuiller, W. url  doi
openurl 
  Titre Mammalian phylogenetic diversity-area relationships at a continental scale Type Article scientifique
  Année 2015 Publication Revue Abrégée Ecology  
  Volume 96 Numéro 10 Pages 2814-2822  
  Mots-Clés Biodiversity; Biogeography; community ecology; conservation; conservation biogeography; habitat loss; habitat loss; null models; overestimate extinction rates; patterns; phylogenetic diversity; richness; species-area; species-area relationship; statistics; strict nested design  
  Résumé In analogy to the species-area relationship (SAR), one of the few laws in ecology, the phylogenetic diversity-area relationship (PDAR) describes the tendency of phylogenetic diversity (PD) to increase with area. Although investigating PDAR has the potential to unravel the underlying processes shaping assemblages across spatial scales and to predict PD loss through habitat reduction, it has been little investigated so far. Focusing on PD has noticeable advantages compared to species richness (SR), since PD also gives insights on processes such as speciation/extinction, assembly rules and ecosystem functioning. Here we investigate the universality and pervasiveness of the PDAR at continental scale using terrestrial mammals as study case. We define the relative robustness of PD (compared to SR) to habitat loss as the area between the standardized PDAR and standardized SAR (i.e., standardized by the diversity of the largest spatial window) divided by the area under the standardized SAR only. This metric quantifies the relative increase of PD robustness compared to SR robustness. We show that PD robustness is higher than SR robustness but that it varies among continents. We further use a null model approach to disentangle the relative effect of phylogenetic tree shape and nonrandom spatial distribution of evolutionary history on the PDAR. We find that, for most spatial scales and for all continents except Eurasia, PDARs are not different from expected by a model using only the observed SAR and the shape of the phylogenetic tree at continental scale. Interestingly, we detect a strong phylogenetic structure of the Eurasian PDAR that can be predicted by a model that specifically account for a finer biogeographical delineation of this continent. In conclusion, the relative robustness of PD to habitat loss compared to species richness is determined by the phylogenetic tree shape but also depends on the spatial structure of PD.  
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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 0012-9658 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1423  
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Auteur Bernard, C.; Escalas, A.; Villeriot, N.; Agogué, H.; Hugoni, M.; Duval, C.; Carré, C.; Got, P.; Sarazin, G.; Jézéquel, D.; Leboulanger, C.; Grossi, V.; Ader, M.; Troussellier, M. url  doi
openurl 
  Titre Very Low Phytoplankton Diversity in a Tropical Saline-Alkaline Lake, with Co-dominance of Arthrospira fusiformis (Cyanobacteria) and Picocystis salinarum (Chlorophyta) Type Article scientifique
  Année 2019 Publication Revue Abrégée Microb Ecol  
  Volume 78 Numéro 3 Pages 603-617  
  Mots-Clés Cyanobacteria; Diversity; Extreme environment; Phytoplankton; Picoeukaryote; Thalassohaline lake  
  Résumé Lake Dziani Dzaha (Mayotte Island, Indian Ocean) is a tropical thalassohaline lake which geochemical and biological conditions make it a unique aquatic ecosystem considered as a modern analogue of Precambrian environments. In the present study, we focused on the diversity of phytoplanktonic communities, which produce very high and stable biomass (mean2014–2015 = 652 ± 179 μg chlorophyll a L−1). As predicted by classical community ecology paradigms, and as observed in similar environments, a single species is expected to dominate the phytoplanktonic communities. To test this hypothesis, we sampled water column in the deepest part of the lake (18 m) during rainy and dry seasons for two consecutive years. Phytoplanktonic communities were characterized using a combination of metagenomic, microscopy-based and flow cytometry approaches, and we used statistical modeling to identify the environmental factors determining the abundance of dominant organisms. As hypothesized, the overall diversity of the phytoplanktonic communities was very low (15 OTUs), but we observed a co-dominance of two, and not only one, OTUs, viz., Arthrospira fusiformis (Cyanobacteria) and Picocystis salinarum (Chlorophyta). We observed a decrease in the abundance of these co-dominant taxa along the depth profile and identified the adverse environmental factors driving this decline. The functional traits measured on isolated strains of these two taxa (i.e., size, pigment composition, and concentration) are then compared and discussed to explain their capacity to cope with the extreme environmental conditions encountered in the aphotic, anoxic, and sulfidic layers of the water column of Lake Dziani Dzaha.  
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  Langue en Langue du Résumé Titre Original  
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  Volume de collection Numéro de collection Edition  
  ISSN 1432-184x ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2494  
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Auteur Alves-Júnior, F.D.A.; Silva, E.D.S.; Araújo, M.D.S.L.C.D.; Cardoso, I.; Bertrand, A.; Souza-Filho, J.F. url  doi
openurl 
  Titre Taxonomy of deep-sea shrimps of the Superfamily Oplophoroidea Dana 1852 (Decapoda: Caridea) from Southwestern Atlantic Type Article scientifique
  Année 2019 Publication Revue Abrégée Zootaxa  
  Volume 4613 Numéro 3 Pages 401-442  
  Mots-Clés Crustacea; Acanthephyridae; New Records; bathypelagic shrimps; deep waters; deep-sea biodiversity; Northeastern Brazil; Oplophoridae  
  Résumé In this paper, we provide some available information about the occurrence and some taxonomic aspects of 19 species from the Superfamily Oplophoroidea in the southwestern Atlantic (Brazilian waters), with the update to 22 species of Oplophoroidea occurring in Brazilian waters. Samples were collected during two sets of surveys. The first was performed in 2009 and 2011 in the Potiguar Basin in northeast of Brazil (03–05°S; 38–35°W; between the States of Ceará and Rio Grande do Norte) under the framework of the project “Avaliação da biota bentônica e planctônica da Bacia Potiguar e Ceará (Bpot)”, with samples collected from bottom trawls in the continental slope at depth ranging from 150–2068 m. Second, under the in the framework of the ABRACOS (Acoustic along the Brazilian coast), performed in 2015 and 2017 on seamounts and offshore areas in Northeast Brazil (Ceará Chain, Rio Grande do Norte and Rocas Atoll, Fernando de Noronha Archipelago and Pernambuco State), with samples with pelagic micronekton and mesopelagic nets, in depths ranging from 50–1260 m. We highlight the occurrence of 14 species of the family Acanthephyridae and 5 species of the family Oplophoridae, including the first occurrences of five species to Brazilian deep waters: Acanthephyra kingsleyi Spence Bate, 1888, Ephyrina ombango Crosnier & Forest, 1973, Meningodora compsa (Chace, 1940), M. longisulca Kikuchi, 1985 and Systellapsis curvispina Crosnier, 1987. These records increase the knowledge on deep-sea shrimps occurring in Southwestern Atlantic.  
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  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 1175-5334 ISBN Médium  
  Région Expédition Conférence  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2584  
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Auteur Galès, A.; Triplet, S.; Geoffroy, T.; Roques, C.; Carré, C.; Le Floc’h, E.; Lanfranchi, M.; Simier, M.; Roque d’Orbcastel, E.; Przybyla, C.; Fouilland, E. url  doi
openurl 
  Titre Control of the pH for marine microalgae polycultures: A key point for CO2 fixation improvement in intensive cultures Type Article scientifique
  Année 2020 Publication Revue Abrégée Journal of CO2 Utilization  
  Volume 38 Numéro Pages 187-193  
  Mots-Clés Carbon yield; Microalgal diversity; pH; Predators  
  Résumé Recently, CO2 recycling for the production of valuable microalgae has acquired substantial interest. Most studies investigating CO2 conversion efficiency in algal cultures were based on single species, although a stabilising effect of algal diversity on biomass production was recently highlighted. However, addition of CO2 into polyalgal cultures requires a careful control of pH; performance of CO2 conversion, growth and carbon biomass production are affected by pH differently, depending on the species of microalgae. This study investigates the efficiency of CO2 conversion by natural marine algal assemblage cultivated in open, land-based raceways (4.5 m3, 10 m2), working as high rate algal ponds (HRAP). Ponds were enriched with nitrogen and phosphate, pure CO2 was added and algal cultures were grown under three different fixed pH levels: pH 6, 7 and 8. The highest conversion of photosynthetically fixed CO2 into carbon biomass (40 %) was reached at pH 7, an intermediate level, due to the partial CO2 asphyxiation of algal predators (copepods, ciliates), while being under the suboptimal conditions for the development of marine amoebae. Under this pH, the theoretical maximal biological conversion of available CO2 into carbon biomass was estimated to be 60 % in naturally inoculated open ponds.  
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  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 2212-9820 ISBN Médium  
  Région Expédition Conférence  
  Notes Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2727  
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Auteur Turon, V.; Trably, E.; Fayet, A.; Fouilland, E.; Steyer, J.-P. url  doi
openurl 
  Titre Raw dark fermentation effluent to support heterotrophic microalgae growth: microalgae successfully outcompete bacteria for acetate Type Article scientifique
  Année 2015 Publication Revue Abrégée Algal Research  
  Volume 12 Numéro Pages 119-125  
  Mots-Clés Bacterial diversity; Biohydrogen; Chlorella sorokiniana; Dark fermentation; Heterotrophic cultivation; Volatile fatty acids (VFAs)  
  Résumé Coupling dark fermentation (DF), which produces hydrogen from diverse effluents or solid waste, and heterotrophic cultivation of microalgae, which produces lipids, carbohydrates and proteins, is a promising and innovative solution for developing sustainable biorefineries. The use of a raw DF effluent, containing acetate and butyrate, to support the heterotrophic growth of Chlorella sorokiniana was investigated. All the acetate in sterilized and unsterilized DF effluent was exhausted in less than three days of heterotrophic cultivation, whereas butyrate was not used by the microalgae. The microalgae biomass reached 0.33 g L− 1 with a carbon yield on acetate of 55%. The algal yield was higher than previously reported for synthetic DF effluent. It was concluded that compounds other than volatile fatty acids were present in the DF effluent and these could be consumed by the microalgae. After the acetate had been exhausted, butyrate was consumed by facultative and strict aerobic bacteria originating from the DF effluent. The concentration of the bacterial community increased during the experiment but did not have any significant impact on heterotrophic microalgae growth. A high microalgal biomass yield was achieved without requiring the DF effluent to be sterilized.  
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  Langue Langue du Résumé Titre Original  
  Éditeur de collection Titre de collection Titre de collection Abrégé  
  Volume de collection Numéro de collection Edition  
  ISSN 2211-9264 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1447  
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