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Auteur Pommier, T.; Douzery, E.J.P.; Mouillot, D. url  doi
openurl 
  Titre (up) Environment drives high phylogenetic turnover among oceanic bacterial communities Type Article scientifique
  Année 2012 Publication Revue Abrégée Biol. Lett.  
  Volume 8 Numéro 4 Pages 562-566  
  Mots-Clés Biogeography; connectivity; diversity; dynamics; patterns; phylogenetic turnover  
  Résumé Although environmental filtering has been observed to influence the biodiversity patterns of marine bacterial communities, it was restricted to the regional scale and to the species level, leaving the main drivers unknown at large biogeographic scales and higher taxonomic levels. Bacterial communities with different species compositions may nevertheless share phylogenetic lineages, and phylogenetic turnover (PT) among those communities may be surprisingly low along any biogeographic or environmental gradient. Here, we investigated the relative influence of environmental filtering and geographical distance on the PT between marine bacterial communities living more than 8000 km apart in contrasted abiotic conditions. PT was high between communities and was more structured by local environmental factors than by geographical distance, suggesting the predominance of a lineage filtering process. Strong phenotype-environment mismatches observed in the ocean may surpass high connectivity between marine microbial communities.  
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  ISSN 1744-9561 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 567  
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Auteur Cuif, M.; Keller, F.; Chateau, O.; Kaplan, D.; Labonne, M.; Lett, C.; Vigliola, L. url  doi
openurl 
  Titre (up) Evaluation of transgenerational isotope labeling of embryonic otoliths in a coral reef damselfish with single and repeated injections of enriched (137)Barium Type Article scientifique
  Année 2014 Publication Revue Abrégée Journal of Experimental Marine Biology and Ecology  
  Volume 459 Numéro Pages 151-159  
  Mots-Clés Barium isotopes; Connectivity; Dascyllus aruanus; La-Icp-Ms; microchemistry; Otolith; Transgenerational marking  
  Résumé Quantifying the larval dispersal component of population connectivity is extremely challenging due to the many difficulties associated with directly observing larvae in their marine environment. Transgenerational isotope labeling is a recent empirical technique that addresses this challenge. It relies on the transmission of an artificially enriched stable isotope (e.g., Ba-137) from gravid females to the embryonic otoliths of their offspring, allowing for mass permanent marking of larvae. Before implementing transgenerational isotope labeling in the wild, it is essential to investigate the transmission longevity of the mark from females to larvae and to assess the potential negative effects on females and their offspring. We injected females of the Humbug damselfish, Dascyllus aruanus, with an enriched Ba-137 solution and reared the resulting progeny to test the marking success and the transmission longevity of the mark, as well as determine potential effects of transgenerational isotope labeling on spawning frequency and size of 1-day eggs and 2-day larvae. Three different single-injection dosages (0.5, 1 and 5 mu g of Ba-137 g(-1) fish weight) were tested, as well as monthly repeated injections of the lowest dosage over a whole reproductive season. We implemented a new method that allows extracting otoliths of newly hatched larvae and analyzing them using laser ablation coupled plasma mass spectrometry (ICP-MS). We showed that for D. aruanus, injection with a low dose (0.5 mu g Ba-137 g(-1), fish weight) produced consistently significantly marked larvae with a half-life for successful enriched Ba mark transmission of approximately 1 month, and that monthly repeated injections of this dose did not negatively impact spawning success or condition of eggs and larvae. Monthly repeated injections of enriched Ba isotope injections at 0.5 mu g Ba-137 g(-1) fish weight will therefore present an effective means of mass marking D. aruanus larvae throughout an entire reproductive season.  
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  ISSN 0022-0981 ISBN Médium  
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  Numéro d'Appel LL @ pixluser @ collection 357  
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Auteur Almoussawi, A.; Lenoir, J.; Jamoneau, A.; Hattab, T.; Wasof, S.; Gallet-Moron, E.; Garzon-Lopez, C.X.; Spicher, F.; Kobaissi, A.; Decocq, G. doi  openurl
  Titre (up) Forest fragmentation shapes the alpha-gamma relationship in plant diversity Type Article scientifique
  Année 2019 Publication Revue Abrégée J. Veg. Sci.  
  Volume Numéro Pages  
  Mots-Clés agricultural landscapes; alpha diversity; anthropogenic disturbances; assemblages; community assembly; community patterns; competition; connectivity; dispersal limitations; gamma diversity; habitat conservation strategies; habitat fragmentation; local-regional richness relationship; metacommunity dynamics; regional species richness; relative importance; saturation; specialists; succession  
  Résumé Questions Forest fragmentation affects biodiversity locally (alpha diversity) and beyond – at relatively larger scales (gamma diversity) – by increasing dispersal and recruitment limitations. Yet, does an increase in fragmentation affect the relationship between alpha and gamma diversity and what can we learn from it? Location Northern France. Methods We surveyed 116 forest patches across three fragmentation levels: none (continuous forest); intermediate (forest patches connected by hedgerows); and high (isolated forest patches). Plant species richness of both forest specialists and generalists was surveyed at five nested spatial resolutions across each forest patch: 1 m(2); 10 m(2); 100 m(2); 1,000 m(2); and total forest patch area. First, we ran log-ratio models to quantify the alpha-gamma relationship. We did that separately for all possible combinations of fragmentation level (none vs intermediate vs high) x spatial scale (e.g., alpha-1 m(2) vs gamma-10 m(2)) x species type (e.g., alpha-specialists vs gamma-specialists). We then used linear mixed-effects models to analyze the effect of fragmentation level, spatial scale, species type and all two-way interaction terms on the slope coefficient extracted from all log-ratio models. Results We found an interaction effect between fragmentation level and species type, such that forest specialists shifted from a linear (i.e., proportional sampling) to a curvilinear plateau (i.e., community saturation) relationship at low and high fragmentation, respectively, while generalists shifted from a curvilinear to a linear pattern. Conclusions The impact of forest fragmentation on the alpha-gamma relationship supports generalist species persistence over forest specialists, with contrasting mechanisms for these two guilds. As fragmentation increases, forest specialists shift from proportional sampling towards community saturation, thus reducing alpha diversity likely due to dispersal limitation. Contrariwise, generalists shift from community saturation towards proportional sampling, thus increasing alpha diversity likely due to an increase in the edge:core ratio. To ensure long-term conservation of forest specialists, one single large forest patch should be preferred over several small ones.  
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  ISSN 1100-9233 ISBN Médium  
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  Notes WOS:000493723100001 Approuvé pas de  
  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2676  
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Auteur McLean, M.J.; Mouillot, D.; Goascoz, N.; Schlaich, I.; Auber, A. doi  openurl
  Titre (up) Functional reorganization of marine fish nurseries under climate warming Type Article scientifique
  Année 2019 Publication Revue Abrégée Glob. Change Biol.  
  Volume 25 Numéro 2 Pages 660-674  
  Mots-Clés English Channel; community; ecosystem; fisheries; recruitment; functional traits; in-situ; connectivity; estuarine; climate change; life-history strategies; ecosystem function; life history; english-channel; Atlantic Multidecadal Oscillation; atlantic multidecadal oscillation; fuzzy-logic; r-selection  
  Résumé While climate change is rapidly impacting marine species and ecosystems worldwide, the effects of climate warming on coastal fish nurseries have received little attention despite nurseries' fundamental roles in recruitment and population replenishment. Here, we used a 26-year time series (1987-2012) of fish monitoring in the Bay of Somme, a nursery in the Eastern English Channel (EEC), to examine the impacts of environmental and human drivers on the spatial and temporal dynamics of fish functional structure during a warming phase of the Atlantic Multidecadal Oscillation (AMO). We found that the nursery was initially dominated by fishes with r-selected life-history traits such as low trophic level, low age and size at maturity, and small offspring, which are highly sensitive to warming. The AMO, likely superimposed on climate change, induced rapid warming in the late 1990s (over 1 degrees C from 1998 to 2003), leading to functional reorganization of fish communities, with a roughly 80% decline in overall fish abundance and increased dominance by K-selected fishes. Additionally, historical overfishing likely rendered the bay more vulnerable to climatic changes due to increased dominance by fishing-tolerant, yet climatically sensitive species. The drop in fish abundance not only altered fish functional structure within the Bay of Somme, but the EEC was likely impacted, as the EEC has been unable to recover from a regime shift in the late 1990s potentially, in part, due to failed replenishment from the bay. Given the collapse of r-selected fishes, we discuss how the combination of climate cycles and global warming could threaten marine fish nurseries worldwide, as nurseries are often dominated by r-selected species.  
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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  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 2523  
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Auteur MUTHS, D.; TESSIER, E.; BOURJEA, J. url  doi
openurl 
  Titre (up) Genetic structure of the reef grouper Epinephelus merra in the West Indian Ocean appears congruent with biogeographic and oceanographic boundaries Type Article scientifique
  Année 2015 Publication Revue Abrégée Marine Ecology-an Evolutionary Perspective  
  Volume 36 Numéro 3 Pages 447-461  
  Mots-Clés Cytochrome b; marine connectivity; microsatellite; reef fish; West Indian Ocean  
  Résumé The reef fauna connectivity of the West Indian Ocean (WIO) is one of the least studied globally. Here we use genetic analyses of the grouper Epinephelus merra (Bloch 1793) to determine patterns of connectivity and to identify barriers to dispersal in this WIO marine area. Phylogeographic and population-level analyses were conducted on cytochrome b sequences and microsatellites (13 loci) from 557 individuals sampled in 15 localities distributed across the West Indian Ocean. Additional samples from the Pacific Ocean were used to benchmark the WIO population structure. The high level of divergence revealed between Indian and Pacific localities (of about 4.5% in sequences) might be the signature of the major tectonic and climatic changes operating at the Plio-Pleistocene transition, congruently with numerous examples of Indo-Pacific speciation. In comparison, the E. merra sequences from the Indian Ocean constitute a monophyletic clade with a low average genetic distance (d < 0.5%). However both genetic markers indicated some structure within this ocean. The main structure revealed was the isolation of the Maldives from the WIO localities (a different group signature identified by clustering analysis, great values of differentiation). Both marker types reveal further significant structure within the WIO, mainly the isolation of the Mascarene Islands (significant AMOVA and isolation-by-distance patterns) and some patchy structure between the northernmost localities and within the Mozambique Channel. The WIO genetic structure of E. merra appeared congruent with main biogeographic boundaries and oceanographic currents.  
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  ISSN 0173-9565 ISBN Médium  
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  Numéro d'Appel MARBEC @ isabelle.vidal-ayouba @ collection 1436  
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