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Auteur (up) Jeanbille, M.; Gury, J.; Duran, R.; Tronczynski, J.; Ghiglione, J.-F.; Agogué, H.; Ben Said, O.; Taib, N.; Debroas, D.; Garnier, C.; Auguet, J.-C. doi  openurl
  Titre Chronic Polyaromatic Hydrocarbon (PAH) Contamination Is a Marginal Driver for Community Diversity and Prokaryotic Predicted Functioning in Coastal Sediments Type Article scientifique
  Année 2016 Publication Revue Abrégée Front. Microbiol.  
  Volume 7 Numéro Pages Unsp-1303  
  Mots-Clés archaeal communities; bacterial communities; benthic biodiversity; chronic contamination; coastal sediment; deep-sea; degrading bacteria; functional diversity; gulf-of-mexico; harbor sediments; horizon oil-spill; microbial communities; pah; polycyclic aromatic-hydrocarbons  
  Résumé Benthic microorganisms are key players in the recycling of organic matter and recalcitrant compounds such as polyaromatic hydrocarbons (PAHs) in coastal sediments. Despite their ecological importance, the response of microbial communities to chronic PAH pollution, one of the major threats to coastal ecosystems, has received very little attention. In one of the largest surveys performed so far on coastal sediments, the diversity and composition of microbial communities inhabiting both chronically contaminated and non-contaminated coastal sediments were investigated using high throughput sequencing on the 18S and 16S rRNA genes. Prokaryotic alpha-diversity showed significant association with salinity, temperature, and organic carbon content. The effect of particle size distribution was strong on eukaryotic diversity. Similarly to alpha-diversity, beta diversity patterns were strongly influenced by the environmental filter, while PAHs had no influence on the prokaryotic community structure and a weak impact on the eukaryotic community structure at the continental scale. However, at the regional scale, PAHs became the main driver shaping the structure of bacterial and eukaryotic communities. These patterns were not found for PICRUSt predicted prokaryotic functions, thus indicating some degree of functional redundancy. Eukaryotes presented a greater potential for their use as PAH contamination biomarkers, owing to their stronger response at both regional and continental scales.  
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  ISSN 1664-302x ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 1662  
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Auteur (up) Loiseau, N.; Gaertner, J.-C.; Kulbicki, M.; Mérigot, B.; Legras, G.; Taquet, M.; Gaertner-Mazouni, N. url  doi
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  Titre Assessing the multicomponent aspect of coral fish diversity: The impact of sampling unit dimensions Type Article scientifique
  Année 2016 Publication Revue Abrégée Ecological Indicators  
  Volume 60 Numéro Pages 815-823  
  Mots-Clés Evenness; Functional diversity; Index sensitivity; Sampling unit dimensions; species richness; Visual censuses  
  Résumé The influence of variations in sampling unit dimensions on the assessment of fish species structuring has been widely documented. However, this issue has been restricted to a very limited range of community and population indices (mainly species richness and density). Here, we have investigated this issue through the analysis of 13 diversity indices related to 3 diversity components (number of species, evenness and functional diversity). We analyzed a large set of 257 standardized underwater visual census (UVC) transects dealing with 254 coral fish species. The sensitivity of the indices to the variation in sampling unit dimensions was studied by comparing a range of 55 couples of transect length and width representing 34 sampling surfaces. We found that the extent and profile of the sensitivity to changes in transect dimensions strongly varied both from one index to another and from one dimension to another (length and width). The most sensitive indices were more strongly impacted by variation in length than width. We also showed that for a fixed transect surface, the couple of chosen length and width may alter the assessment of indices related to each of the three main diversity components studied. Some widely used diversity indices, such as species richness and Shannon index, appeared to be very sensitive to changes in transect length and width. In contrast, while still very little used in coral fish studies, two functional diversity indices (FDiv, FEve), and to a lesser extent an evenness index (Berger–Parker), remained robust in the face of change in sampling dimensions. By showing that the variation in sampling dimensions (length, width and surface) may impact diversity indices in a contrasting manner, we stress the need to take into account the sensitivity of the indices to this criterion in the process of selection of the indices to be analyzed in diversity studies. Finally, we found that 30 m long*5 m wide transects might be a suitable compromise size for assessing the patterns of each of the three major complementary components of coral fish diversity.  
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  ISSN 1470-160x ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1320  
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Auteur (up) Loiseau, N.; Legras, G.; Kulbicki, M.; Mérigot, B.; Harmelin-Vivien, M.; Mazouni, N.; Galzin, R.; Gaertner, J.C. doi  openurl
  Titre Multi-component β-diversity approach reveals conservation dilemma between species and functions of coral reef fishes Type Article scientifique
  Année 2017 Publication Revue Abrégée J. Biogeogr.  
  Volume 44 Numéro 3 Pages 537-547  
  Mots-Clés assemblages; Beta diversity; Beta-diversity; biodiversity; climate; coral reef fish; environmental dissimilarity; functional diversity; global patterns; models; nestedness; null; partitioning; turnover; vulnerability  
  Résumé AimWe applied a multicomponent approach based on the decomposition of taxonomic (both presence-absence and abundance) and functional beta diversity to determine the influence of ecological factors in shaping spatial distribution diversity of coral reef fishes, and the implications for conservation decisions. LocationLagoons of ten atolls characterized by low human pressure but with contrasted geomorphology in the Tuamotu Archipelago, French Polynesia. MethodsWe computed beta diversities and their partitioning components, both at local (inter-transect, from 200m to 10km) and large (among atolls, from 22 to 350km) spatial scales. Null models were applied to test whether the observed beta diversity differed from random expectation. Multiple generalized dissimilarity models were run to test which environmental factors were the best predictors of observed beta diversities. ResultsBeta diversity was indistinguishable from randomness at both spatial scales. Species remained generally interchangeable among transects within an atoll and to some extent among atolls. However, strong deviance explained by models showed that the number of species, the number of individuals and functional traits present in transects and atolls were determined by deterministic factors (i.e. environmental factors). Modelling each beta diversity component separately also revealed partial mismatch among atolls and among species and functional dissimilarities. The influence of environmental variables strongly varied among atolls, species and functional dissimilarities. Main conclusionsBy revealing the spatial scaling of ecological factors and partial congruence among species and functional diversity, assessment of beta diversity provides insight into conservation planning. Our results support the idea that conservation planning applied to protect taxonomic diversity cannot be fully extended to functional diversity. We have addressed the dilemma of which diversity component should be favoured in conservation strategies.  
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  ISSN 0305-0270 ISBN Médium  
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  Numéro d'Appel MARBEC @ alain.herve @ collection 2117  
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Auteur (up) Manna, L.R.; Villeger, S.; Rezende, C.F.; Mazzoni, R. doi  openurl
  Titre High intraspecific variability in morphology and diet in tropical stream fish communities Type Article scientifique
  Année 2019 Publication Revue Abrégée Ecol. Freshw. Fish  
  Volume 28 Numéro 1 Pages 41-52  
  Mots-Clés approach reveals; assemblages; body-size; community ecology; competition; ecology; functional diversity; functional traits; habitat use; originality; plasticity; rainforest stream; savannah stream; specialisation; specialization; traits  
  Résumé Functional diversity of fish communities has been measured according to (a) interspecific variability, assuming that intraspecific variability is negligible, or (b) morphological differences, as good descriptors of complex functions, such as diet. These two assumptions have been scarcely tested on the individual level, especially in species-rich tropical ecosystems. Here, we adapted intraspecific specialisation (ISpe) and intraspecific originality indices (IOri) to assess complementary components of intraspecific variability. Next, we applied these indices to evaluate the intra- and interspecific variability of morphological and diet traits in two contrasting Brazilian stream-dwelling fish assemblages (rainforest and savannah). We also compared correlations between morphology and diet at the individual and species level to test whether accounting for intraspecific variability increases the predictability of diet due to morphological differences. Significant contributions of intraspecific variability to differences between fish were revealed for morphology and diet. Intraspecific variability in the diet was higher than that in morphology in both assemblages. The ISpe was positively correlated to IOri in the diet of both ecosystems. The morphological-dietary relationships were significant but weak at both individual and species levels. Our findings highlight the importance of measuring individual variability and accounting for complementary components of the intraspecific variability (ISpe and IOri). Importantly, we showed that the variability in morphology does not predict diet variability at both intra- and interspecific levels. Thus, high intraspecific variability in morphology and diet challenges the use of functional traits measured at the species level to describe the functional diversity of different fish assemblages.  
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  Volume de collection Numéro de collection Edition  
  ISSN 0906-6691 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2472  
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Auteur (up) Mazel, F.; Guilhaumon, F.; Mouquet, N.; Devictor, V.; Gravel, D.; Renaud, J.; Cianciaruso, M.V.; Loyola, R.; Diniz, J.A.F.; Mouillot, D.; Thuiller, W. url  doi
openurl 
  Titre Multifaceted diversity-area relationships reveal global hotspots of mammalian species, trait and lineage diversity Type Article scientifique
  Année 2014 Publication Revue Abrégée Global Ecology and Biogeography  
  Volume 23 Numéro 8 Pages 836-847  
  Mots-Clés Conservation biogeography; Hill's numbers; biodiversity hotspots; congruent; conservation priorities; diversity indices; ecoregions; endemism; evolutionary; functional diversity-area; histories; mammals; phylogenetic diversity; phylogenetic diversity-area; relationship; richness gradients; spatial-patterns; species-area relationship  
  Résumé Aim To define biome-scale hotspots of phylogenetic and functional mammalian biodiversity (PD and FD, respectively) and compare them with 'classical' hotspots based on species richness (SR) alone. Location Global. Methods SR, PD and FD were computed for 782 terrestrial ecoregions using the distribution ranges of 4616 mammalian species. We used a set of comprehensive diversity indices unified by a recent framework incorporating the relative species coverage in each ecoregion. We built large-scale multifaceted diversity-area relationships to rank ecoregions according to their levels of biodiversity while accounting for the effect of area on each facet of diversity. Finally we defined hotspots as the top-ranked ecoregions. Results While ignoring relative species coverage led to a fairly good congruence between biome-scale top ranked SR, PD and FD hotspots, ecoregions harbouring a rich and abundantly represented evolutionary history and FD did not match with the top-ranked ecoregions defined by SR. More importantly PD and FD hotspots showed important spatial mismatches. We also found that FD and PD generally reached their maximum values faster than SR as a function of area. Main conclusions The fact that PD/FD reach their maximum value faster than SR could suggest that the two former facets might be less vulnerable to habitat loss than the latter. While this point is expected, it is the first time that it has been quantified at a global scale and should have important consequences for conservation. Incorporating relative species coverage into the delineation of multifaceted hotspots of diversity led to weak congruence between SR, PD and FD hotspots. This means that maximizing species number may fail to preserve those nodes (in the phylogenetic or functional tree) that are relatively abundant in the ecoregion. As a consequence it may be of prime importance to adopt a multifaceted biodiversity perspective to inform conservation strategies at a global scale.  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 722  
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