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Auteur Mazel, F.; Renaud, J.; Guilhaumon, F.; Mouillot, D.; Gravel, D.; Thuiller, W.
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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ISSN (up) 0012-9658 ISBN Médium
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1423
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Auteur Reynolds, P.L.; Stachowicz, J.J.; Hovel, K.; Bostrom, C.; Boyer, K.; Cusson, M.; Eklof, J.S.; Engel, F.G.; Engelen, A.H.; Eriksson, B.K.; Fodrie, F.J.; Griffin, J.N.; Hereu, C.M.; Hori, M.; Hanley, T.C.; Ivanov, M.; Jorgensen, P.; Kruschel, C.; Lee, K.-S.; McGlathery, K.; Moksnes, P.-O.; Nakaoka, M.; O'Connor, M.I.; O'Connor, N.E.; Orth, R.J.; Rossi, F.; Ruesink, J.; Sotka, E.E.; Thormar, J.; Tomas, F.; Unsworth, R.K.F.; Whalen, M.A.; Duffy, J.E.
Titre Latitude, temperature, and habitat complexity predict predation pressure in eelgrass beds across the Northern Hemisphere Type Article scientifique
Année 2018 Publication Revue Abrégée Ecology
Volume 99 Numéro 1 Pages 29-35
Mots-Clés patterns; communities; diversity; ecosystems; temperature; seagrasses; eutrophication; predation; biogeography; prey; top-down control; enrichment; latitude; mesograzer; seagrass; species interactions; water temperature; Zostera
Résumé Latitudinal gradients in species interactions are widely cited as potential causes or consequences of global patterns of biodiversity. However, mechanistic studies documenting changes in interactions across broad geographic ranges are limited. We surveyed predation intensity on common prey (live amphipods and gastropods) in communities of eelgrass (Zostera marina) at 48 sites across its Northern Hemisphere range, encompassing over 37 degrees of latitude and four continental coastlines. Predation on amphipods declined with latitude on all coasts but declined more strongly along western ocean margins where temperature gradients are steeper. Whereas insitu water temperature at the time of the experiments was uncorrelated with predation, mean annual temperature strongly positively predicted predation, suggesting a more complex mechanism than simply increased metabolic activity at the time of predation. This large-scale biogeographic pattern was modified by local habitat characteristics; predation declined with higher shoot density both among and within sites. Predation rates on gastropods, by contrast, were uniformly low and varied little among sites. The high replication and geographic extent of our study not only provides additional evidence to support biogeographic variation in predation intensity, but also insight into the mechanisms that relate temperature and biogeographic gradients in species interactions.
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ISSN (up) 0012-9658 ISBN Médium
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Numéro d'Appel MARBEC @ alain.herve @ collection 2254
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Auteur Leruste, A.; Villeger, S.; Malet, N.; De Wit, R.; Bec, B.
Titre Complementarity of the multidimensional functional and the taxonomic approaches to study phytoplankton communities in three Mediterranean coastal lagoons of different trophic status Type Article scientifique
Année 2018 Publication Revue Abrégée Hydrobiologia
Volume 815 Numéro 1 Pages 207-227
Mots-Clés classification; Classification; disturbance; diversity; ecology; Functional entity; Functional traits; lake phytoplankton; marine-phytoplankton; patterns; size; synechococcus; Taxonomic diversity; traits
Résumé We used the individual-based multidimensional functional diversity and the taxonomic approaches in a complementary way to describe phytoplankton communities in three coastal lagoons with different eutrophication status in the South of France. We sampled communities during three seasons, i.e., in autumn, spring, and summer. Using classical taxonomy, 107 taxa/morphotypes were identified in the nine communities. The individual-based functional approach allowed grouping these individuals into 20 functional entities according to their values for 5 traits related to trophic adaptations (cell size, mobility, trophic regime, coloniality, and pelagic/benthic life). Some species (e.g., Prorocentrum micans) emerged in multiple functional entities, showing the importance to consider intraspecific variability. The functional description of phytoplankton communities better reflected the hydrological functioning and the different eutrophication status of the lagoons than the taxonomic approach. Specific functional adaptations were identified in the nine communities. For example, phytoplankton organisms with heterotrophic and potentially mixotrophic abilities occurred when the availability of inorganic nutrient decreased, or when organic matter and small preys were potentially the main nutrient resources. The limitation has also favored small cells highly competitive for nutrients. Using functional indices together with taxonomic description has also helped revealing important aspects of community assembly, such as competitive exclusion in summer.
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Langue English Langue du Résumé Titre Original
Éditeur de collection Titre de collection Titre de collection Abrégé
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ISSN (up) 0018-8158 ISBN Médium
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Numéro d'Appel MARBEC @ alain.herve @ collection 2322
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Auteur Oikonomou, A.; Leprieur, F.; Leonardos, I.D.
Titre Biogeography of freshwater fishes of the Balkan Peninsula Type Article scientifique
Année 2014 Publication Revue Abrégée Hydrobiologia
Volume 738 Numéro 1 Pages 205-220
Mots-Clés Balkan Peninsula; Beta diversity; Bioregionalisation; Conservation biogeography; Vulnerability; ancient lakes; biodiversity conservation; endemism; freshwater fish; global patterns; mitochondrial-dna sequences; north-america; phylogeography; species richness
Résumé Delineating biogeographical regions is a critical step towards the establishment and evaluation of conservation priorities. In the present study, we analysed the distribution patterns of the freshwater fish of an understudied European biodiversity hotspot, the Balkan Peninsula. Based on the most extensive available database of native freshwater fish species distributions, we performed a hierarchical clustering analysis to identify the major biogeographical regions of the Balkan Peninsula. We also highlighted the 'hottest hotspots' of freshwater fish diversity across the delimited biogeographical regions by describing the patterns of species richness, endemic and vulnerable species; indicator species were also determined. The bioregionalisation scheme consisted of eight groups of drainage basins that correspond to distinct regions of the Balkan Peninsula. Overall, the delineated biogeographical regions varied in terms of species richness, endemism, vulnerability (i.e. extinction threats) and indicator species composition. From a conservation perspective, this study emphasises the prioritisation of areas characterised by high levels of irreplaceability (endemism) and vulnerability (i.e. the Attikobeotia region, Ionian Sea and Prespa Lakes) and stresses the necessity of implementing a network of protected freshwater areas across the Balkan Peninsula.
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Langue English Langue du Résumé Titre Original
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ISSN (up) 0018-8158 ISBN Médium
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 454
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Auteur ARNAUD-HAOND, S.; MOALIC, Y.; HERNANDEZ-GARCIA, E.; EGUILUZ, V.M.; ALBERTO, F.; SERRAO, E.A.; DUARTE, C.M.
Titre Disentangling the Influence of Mutation and Migration in Clonal Seagrasses Using the Genetic Diversity Spectrum for Microsatellites Type Article scientifique
Année 2014 Publication Revue Abrégée Journal Of Heredity
Volume 105 Numéro 4 Pages 532-541
Mots-Clés clonality; genetic divergence; Genetic Diversity Spectrum; microsatellites; Seagrass; stepwise mutation
Résumé The recurrent lack of isolation by distance reported at regional scale in seagrass species was recently suggested to stem from stochastic events of large-scale dispersal. We explored the usefulness of phylogenetic information contained in microsatellite loci to test this hypothesis by using the Genetic Diversity Spectrum (GDS) on databases containing, respectively, 7 and 9 microsatellites genotypes for 1541 sampling units of Posidonia oceanica and 1647 of Cymodocea nodosa. The simultaneous increase of microsatellite and geographic distances that emerges reveals a coherent pattern of isolation by distance in contrast to the chaotic pattern previously described using allele frequencies, in particular, for the long-lived P. oceanica. These results suggest that the lack of isolation by distance, rather than the resulting from rare events of large-scale dispersal, reflects at least for some species a stronger influence of mutation over migration at the scale of the distribution range. The global distribution of genetic polymorphism may, therefore, result predominantly from ancient events of step-by-step (re)colonization followed by local recruitment and clonal growth, rather than contemporary gene flow. The analysis of GDS appears useful to unravel the evolutionary forces influencing the dynamics and evolution at distinct temporal and spatial scales by accounting for phylogenetic information borne by microsatellites, under an appropriate mutation model. This finding adds nuance to the generalization of the influence of large-scale dispersal on the dynamics of seagrasses.
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Éditeur de collection Titre de collection Titre de collection Abrégé
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ISSN (up) 0022-1503 ISBN Médium
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Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1138
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