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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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Volume de collection Numéro de collection Edition
ISSN 0022-1503 ISBN Médium
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Auteur Arnaud-Haond, S.; Stoeckel, S.; Bailleul, D.
Titre New insights into the population genetics of partially clonal organisms: When seagrass data meet theoretical expectations Type Article scientifique
Année 2020 Publication Revue Abrégée Mol. Ecol.
Volume 29 Numéro 17 Pages 3248-3260
Mots-Clés asexual reproduction; climate-change; clonal growth; differentiation; dispersal; diversity; efficiency; growth; larval dispersal; marine meadows; mating system; migration; ria formosa; seagrass; zostera-marina
Résumé Seagrass meadows are among the most important coastal ecosystems in terms of both spatial extent and ecosystem services, but they are also declining worldwide. Understanding the drivers of seagrass meadow dynamics is essential for designing sound management, conservation and restoration strategies. However, poor knowledge of the effect of clonality on the population genetics of natural populations severely limits our understanding of the dynamics and connectivity of meadows. Recent modelling approaches have described the expected distributions of genotypic and genetic descriptors under increasing clonal rates, which may help us better understand and interpret population genetics data obtained for partial asexuals. Here, in the light of these recent theoretical developments, we revisited population genetics data for 165 meadows of four seagrass species. Contrasting shoot lifespan and rhizome turnover led to the prediction that the influence of asexual reproduction would increase along a gradient fromZostera noltiitoZostera marina, Cymodocea nodosaandPosidonia oceanica, with increasing departure from Hardy-Weinberg equilibrium (F-is), mostly towards heterozygote excess, and decreasing genotypic richness (R). This meta-analysis provides a nested validation of this hypothesis at both the species and meadow scales through a significant relationship betweenF(is)andRwithin each species. By empirically demonstrating the theoretical expectations derived from recent modelling approaches, this work calls for the use of Hardy-Weinberg equilibrium (F-is) rather than only the strongly sampling-sensitiveRto assess the importance of clonal reproduction (c), at least when the impact of selfing onF(is)can be neglected. The results also emphasize the need to revise our appraisal of the extent of clonality and its influence on the dynamics, connectivity and evolutionary trajectory of partial asexuals in general, including in seagrass meadows, to develop the most accurate management strategies.
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Volume de collection Numéro de collection Edition
ISSN 0962-1083 ISBN Médium
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Notes WOS:000563628600001 Approuvé pas de
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Auteur BECHELER, R.; BENKARA, E.; MOALIC, Y.; HILY, C.; ARNAUD-HAOND, S.
Titre Scaling of processes shaping the clonal dynamics and genetic mosaic of seagrasses through temporal genetic monitoring Type Article scientifique
Année 2014 Publication Revue Abrégée Heredity
Volume 112 Numéro 2 Pages 114-121
Mots-Clés clonality; Seagrass; spatio-temporal genetic structure; Zostera marina
Résumé Theoretically, the dynamics of clonal and genetic diversities of clonal plant populations are strongly influenced by the competition among clones and rate of seedling recruitment, but little empirical assessment has been made of such dynamics through temporal genetic surveys. We aimed to quantify 3 years of evolution in the clonal and genetic composition of Zostera marina meadows, comparing parameters describing clonal architecture and genetic diversity at nine microsatellite markers. Variations in clonal structure revealed a decrease in the evenness of ramet distribution among genets. This illustrates the increasing dominance of some clonal lineages (multilocus lineages, MLLs) in populations. Despite the persistence of these MLLs over time, genetic differentiation was much stronger in time than in space, at the local scale. Contrastingly with the short-term evolution of clonal architecture, the patterns of genetic structure and genetic diversity sensu stricto (that is, heterozygosity and allelic richness) were stable in time. These results suggest the coexistence of (i) a fine grained (at the scale of a 20 x 30 m quadrat) stable core of persistent genets originating from an initial seedling recruitment and developing spatial dominance through clonal elongation; and (ii) a local (at the scale of the meadow) pool of transient genets subjected to annual turnover. This simultaneous occurrence of initial and repeated recruitment strategies highlights the different spatial scales at which distinct evolutionary drivers and mating systems (clonal competition, clonal growth, propagule dispersal and so on) operate to shape the dynamics of populations and the evolution of polymorphism in space and time.
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Volume de collection Numéro de collection Edition
ISSN 0018-067x ISBN Médium
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Auteur Cardoso de Melo, C.; Cavalcanti Soares, A.P.; Pelage, L.; Eduardo Nole, L.; Fredou, T.; Lira, A.S.; Ferreira, B.P.; Bertrand, A.; Lucena-Fredou, F.
Titre Haemulidae distribution patterns along the Northeastern Brazilian continental shelf and size at first maturity of the most abundant species Type Article scientifique
Année 2020 Publication Revue Abrégée Reg. Stud. Mar. Sci.
Volume 35 Numéro Pages 101226
Mots-Clés habitat; seagrass; diversity; coral-reef fish; archipelago; ceara state; grunts haemulidae; maturation; pernambuco; plumieri teleostei haemulidae
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Langue English Langue du Résumé Titre Original
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Volume de collection Numéro de collection Edition
ISSN 2352-4855 ISBN Médium
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Auteur Clavier, J.; Chauvaud, L.; Carlier, A.; Amice, E.; van der Geest, M.; Labrosse, P.; Diagne, A.; Hily, C.
Titre Aerial and underwater carbon metabolism of a Zostera noltii seagrass bed in the Banc d'Arguin, Mauritania Type Article scientifique
Année 2011 Publication Revue Abrégée Aquatic Botany
Volume 95 Numéro Pages 24-30
Mots-Clés Zostera noltii Seagrass Metabolism Intertidal Respiration Primary production Africa Isotope wadden sea marine angiosperms seasonal-variation coastal lagoon hornem photosynthesis oxygen respiration dynamics dioxide
Résumé Community respiration and primary production were measured in a dense intertidal Zostera noltii bed on the Banc d'Arguin, Mauritania (West Africa) under aerial and submerged conditions. Metabolism was studied in situ in dark and transparent benthic chambers. CO(2) fluxes in the air were measured over a series of short-term incubations (3 min) using an infrared gas analyzer. Dissolved inorganic carbon fluxes were calculated from concentration changes during one-hour underwater incubations. Air and underwater irradiance levels were measured every minute throughout the experiments. Carbon respiration was lower in the air (2.2 mmol m(-2) h(-1)) than underwater (5.0 mmol m(-2) h(-1)); similarly, a production-irradiance model fitted to the data indicated that gross maximal photosynthetic rate was markedly lower during emergence (6.0 mmol C m(-2) h(-1)) than under water (42.7 mmol C m(-2) h(-1)). The delta(13)C values observed in shoots indicated a decrease in atmospheric CO(2) contribution, compared to dissolved inorganic carbon, in Z. noltii metabolism along a depth gradient within a single location. As the seagrass bed remains under a thin layer of water at low tide at the studied site, the large difference in primary production can be mainly attributed to photosynthesis inhibition by high pH and oxygen concentration, as well as to the negative feedback of self-shading by seagrass leaves during emersion. The observed differences in respiration can be explained by the oxygen deficit at night during low tide near the sediment surface, a deficit that is consistent with the abundance of anoxia-tolerant species. (C) 2011 Elsevier B.V. All rights reserved.
Adresse [Clavier, Jacques] IUEM, CNRS, UMR 6539, LEMAR,Lab Sci Environm Marin, F-29280 Plouzane, France. [Van der Geest, Matthijs] NIOZ, Dept Marine Ecol, NL-1790 AB Den Burg, Netherlands. [Labrosse, Pierre; Diagne, Ahmed] IMROP, Nouadhibou, Mauritania. Clavier, J (reprint author), IUEM, CNRS, UMR 6539, LEMAR,Lab Sci Environm Marin, Pl Nicolas Copernic, F-29280 Plouzane, France. Jacques.Clavier@univ-brest.fr
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ISSN 0304-3770 ISBN Médium
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Notes ISI Document Delivery No.: 781BF Times Cited: 2 Cited Reference Count: 72 Clavier, Jacques Chauvaud, Laurent Carlier, Antoine Amice, Erwan Van der Geest, Matthijs Labrosse, Pierre Diagne, Ahmed Hily, Christian Franco-Mauritanian PACOBA project; Oceanographic and Fisheries Research Mauritanian Institute (IMROP); Banc d'Arguin National Park (PNBA) This study was funded by the Franco-Mauritanian PACOBA project. We thank the Oceanographic and Fisheries Research Mauritanian Institute (IMROP) and the Banc d'Arguin National Park (PNBA) for their support. Elsevier science bv Amsterdam Approuvé pas de
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