Éditeur(s) : Wiley-blackwell Publishing, Inc
Résumé : Red shrimp, Farfantepenaeus brasiliensis, larvae's response to different concentrations of live foods (diatoms Chaetoceros gracilis: 20-100 x 103 cells/mL; flagellate Tetraselmis chuii: 2-10 x 103 cells/mL and Artemia nauplii [NA]: 1-5 NA/mL) was investigated in three experiments. Experimental assessments were based on four variables: survival rate, weight gain, development index (DI), and resistance to salinity stress. A combination of C. gracilis 80 x 103 cells/mL, T. chuii 2 x 103 cells/mL, and Artemia 4 NA/mL provided the best experimental response. Specifically, F. brasiliensis larvae fed with the above-mentioned optimal concentrations of microalgae and Artemia grew faster and reached the postlarval stage in less time (168 h) than larvae in other feeding regimes evaluated. The effect of C. gracilis concentration on larval growth, survival, and the DI demonstrated that microalgae-based foods could be a highly productive alternative to more traditional aquaculture feeding regimes.
Journal Of The World Aquaculture Society (0893-8849) (Wiley-blackwell Publishing, Inc), 2010-06 , Vol. 41 , N. 3 , P. 402-410

Droits : Copyright by the World Aquaculture Society 2010
http://archimer.ifremer.fr/doc/00028/13928/11639.pdf
DOI:10.1111/j.1749-7345.2010.00381.x
http://archimer.ifremer.fr/doc/00028/13928/

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
BACKGROUND: The RH blood group system has many RHCE variant alleles that have arisen through gene conversion or nucleotide changes. Two probands, with red blood cells (RBCs) that were D+C+E-c+(w) e+ were sent to our laboratories to resolve the weak c expression. STUDY DESIGN AND METHODS: Hemagglutination tests were performed by automated and manual procedures. Genomic DNA analysis was performed by sequencing of Exons 1 to 10 of RHCE and RHD. RESULTS: The probands' RBCs did not react with standard monoclonal anti-E reagents from Bio-Rad, Diagast, DiaMed, Immucor, Ortho, and Quotient. The RBCs reacted variably with anti-c reagents from Diagast, DiaMed, Immucor, or Ortho and did not react with the Quotient anti-c reagent. Surprisingly, sequencing results of RHCE showed the presence of C/G at Position 676 (E/e polymorphism) and the association of the E polymorphism with a 734T>C transition in Exon 5 of the RHCE, encoding a Leu245Pro amino acid substitution in the mature RhcE polypeptide. Replacement of leucine 245 by proline in the eighth transmembrane domain of the RhcE protein may have a steric effect on the protein such that most anti-E reagents do not bind and the interaction between anti-c and c antigen is also affected. CONCLUSION: We report a novel RHCE*cE allele, RHCE*cE734C, which was assigned the provisional ISBT allele name RHCE*cE.14 or RHCE*03.14. It was found in two probands whose RBCs had weakened c expression and typed E- with conventional anti-E reagents. These data, once again, highlight the fact that the genotype does not always reflect the phenotype.
ISSN: 0041-1132

hal-00839022
https://hal.archives-ouvertes.fr/hal-00839022
DOI : 10.1111/j.1537-2995.2012.03860.x
PUBMED : 22958092

Éditeur(s) : John Wiley & Sons Ltd
Résumé : 1. The development of macroalgae to the detriment of corals is now one of the major threats to coral reefs. Herbivorous fishes are partly responsible for algal regulation on coral reefs and their overexploitation favours the shift from scleractinian coral-dominated systems towards macroalgae-dominated systems. 2. Marine protected areas (MPAs) that have been established worldwide may benefit coral reefs through the maintenance of high densities of herbivorous fishes which regulate algal growth. 3. The paper assesses whether small MPAs in the Caribbean are able to enhance herbivorous fish stock and by controlling macroalgae help to maintain reef ecosystems. A visual census using band-transects was undertaken around Guadeloupe island where marine reserves have been in place since 1979. The effects of MPAs on both benthic communities and herbivorous fishes are examined. 4. Inside MPAs, herbivorous fish biomass was almost twice as high as outside MPAs and macroalgal cover was significantly lower. Fish size class distributions revealed that large individuals occurred mainly inside MPAs and that few male individuals were found outside MPAs. Copyright (C) 2010 John Wiley & Sons, Ltd.
Aquatic Conservation-marine And Freshwater Ecosystems (1052-7613) (John Wiley & Sons Ltd), 2010-07 , Vol. 20 , N. 5 , P. 516-524

Droits : 2010 John Wiley & Sons, Ltd.
http://archimer.ifremer.fr/doc/00011/12214/9551.pdf
DOI:10.1002/aqc.1118
http://archimer.ifremer.fr/doc/00011/12214/

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
ISSN: 0022-2720

hal-01682103
https://hal.univ-antilles.fr/hal-01682103
DOI : 10.1046/j.1365-2818.2003.01171.x

Éditeur(s) : Wiley-blackwell Publishing, Inc
Résumé : Seagrasses structure some of the world's key coastal ecosystems presently in decline due to human activities and global change. The ability to cope with environmental changes and the possibilities for shifts in distribution range depend largely on their evolvability and dispersal potential. As large-scale data usually show strong genetic structure for seagrasses, finer-grained work is needed to understand the local processes of dispersal, recruitment and colonization that could explain the apparent lack of exchange across large distances. We aimed to assess the fine-grained genetic structure of one of the most important and widely distributed seagrasses, Zostera marina, from seven meadows in Brittany, France. Both classic population genetics and network analysis confirmed a pattern of spatial segregation of polymorphism at both regional and local scales. One location exhibiting exclusively the variety 'angustifolia' did not appear more differentiated than the others, but instead showed a central position in the network analysis, confirming the status of this variety as an ecotype. This phenotypic diversity and the high allelic richness at nine microsatellites (2.33-9.67 alleles/locus) compared to levels previously reported across the distribution range, points to Brittany as a centre of diversity for Z. marina at both genetic and phenotypic levels. Despite dispersal potential of several 100 m, a significant pattern of genetic differentiation, even at fine-grained scale, revealed 'genetic patchiness'. Meadows seem to be composed of a mosaic of clones with distinct origins in space and time, a result that calls into question the accuracy of the concept of populations for such partially clonal species.
Molecular Ecology (0962-1083) (Wiley-blackwell Publishing, Inc), 2010-06 , Vol. 19 , N. 12 , P. 2394-2407

Droits : 2010 Blackwell Publishing Ltd
http://archimer.ifremer.fr/doc/00006/11690/8499.pdf
DOI:10.1111/j.1365-294X.2010.04649.x
http://archimer.ifremer.fr/doc/00006/11690/

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
: In non-mammalian vertebrates, serotonin (5-HT)-producing neurons exist in the paraventricular organ (PVO), a diencephalic structure containing cerebrospinal fluid (CSF)-contacting neurons exhibiting 5-HT or dopamine (DA) immunoreactivity. Because the brain of the adult teleost is known for its neurogenic activity supported, for a large part, by radial glial progenitors, this study addresses the origin of newborn 5-HT neurons in the hypothalamus of adult zebrafish. In this species, the PVO exhibits numerous radial glial cells (RGCs) whose somata are located at a certain distance from the ventricle. To study relationships between RGCs and 5-HT CSF-contacting neurons, we performed 5-HT immunohistochemistry in transgenic tg(cyp19a1b-GFP) zebrafish in which RGCs are labelled with GFP under the control of the cyp19a1b promoter. We show that the somata of the 5-HT neurons are located closer to the ventricle than those of RGCs. RGCs extend towards the ventricle cytoplasmic processes that form a continuous barrier along the ventricular surface. In turn, 5-HT neurons contact the CSF via processes that cross this barrier through small pores. Further experiments using proliferating cell nuclear antigen or 5-bromo-2'-deoxyuridine indicate that RGCs proliferate and give birth to 5-HT neurons migrating centripetally instead of centrifugally as in other brain regions. Furthermore, treatment of adult zebrafish with tryptophan hydroxylase inhibitor causes a significant decrease in the number of proliferating cells in the PVO, but not in the mediobasal hypothalamus. These data point to the PVO as an intriguing region in which 5-HT appears to promote genesis of 5-HT neurons that accumulate along the brain ventricles and contact the CSF.
ISSN: 0953-816X

inserm-00866212
http://www.hal.inserm.fr/inserm-00866212
DOI : 10.1111/ejn.12348
PUBMED : 23981075

Éditeur(s) : HAL CCSD Wiley
Résumé :  
Pollination ecology and reproductive success of Jack-in-the-pulpit (Arisaema triphyllum) were studied in two natural populations in Québec, Canada. Individual A. triphyllum plants can be of three types: male, female or bisexual. In both populations studied, the presence of bisexual inflorescences was not negligible (13%), where 'female' and 'male' bisexual plants were categorised according to the relative number of stamens and ovaries. 'Male bisexual' plants produce only pollen and 'female bisexual' plants produce only fruit. Hence, A. triphyllum is a true dioecious plant, as each plant only reproduces through either the male or the female function. 'Female bisexual' plants were equivalent to female plants in terms of visitation rate by insects, fructification rate and production of berries and seeds. Neither agamospermy in female plants nor self-pollination in 'female bisexual' plants was found, thus A. triphyllum relies on insects for cross-pollination. Despite the long flowering cycle, a low visitation rate was documented: only 20-40% of inflorescences were visited, according to gender, by a mean of 1.5 insects. In this study, Mycetophilidae represented the most generically diversified and abundant family, as well as the most efficient insect pollinator, especially the genera Docosia and Mycetophila.
ISSN: 1435-8603

hal-01032127
https://hal.archives-ouvertes.fr/hal-01032127
DOI : 10.1111/j.1438-8677.2009.00192.x

Éditeur(s) : HAL CCSD Wiley-VCH Verlag
Résumé : International audience
Saccharopolyspora rectivirgula is the principal cause of farmer's lung disease (FLD). Serodiagnosis is based on immunoprecipitation techniques or enzyme immunoassays with homemade crude antigens and is not standardized. We aimed to produce specific recombinant antigens for the development of a standardized ELISA. We recruited 41 patients and 43 healthy exposed controls from five university hospital pneumology departments in France and Switzerland. S. rectivirgula proteins were extracted, separated by 2D electrophoresis, and subjected to Western blotting, with sera from FLD patients or controls. FLD-specific proteins were identified by MS and were produced as recombinant antigens. The diagnostic performance of ELISA tests using the recombinant antigens was assessed with all the sera from FLD patients and controls. We identified 25 FLD-specific proteins, some of which play important roles in transport, nutrition, or virulence. We produced 17 of these proteins as recombinant antigens and assessed their suitability for inclusion in the ELISA test. A combination of three of these proteins (SR1FA, SR17, and SR22) proved remarkably effective at discriminating between patients and controls, with a sensitivity of 83% and a specificity of 77%. The recombinant antigens produced in this study constitute a major step toward the improvement of diagnostic performance and the standardization of FLD serodiagnosis.
ISSN: 1862-8346

hal-01115880
https://hal.archives-ouvertes.fr/hal-01115880
DOI : 10.1002/prca.201400024
PUBMED : 25264606

Éditeur(s) : HAL CCSD Wiley-Blackwell
Résumé : International audience
Abstract Numerous freshwater species are consumed or exploited through artisanal fisheries in the rivers of the islands of Guadeloupe, French West Indies. Autochthonous production of organic matter is limited in these flowing rivers and is mainly represented by scarce filamentous green algae and an abundant epilithic biofilm growing on wet stones in the river bed. Stable isotope analysis was used to quantify the relative importance of biofilm and other riverine allochthonous and autochthonous food sources in the diet of tropical shrimps (Palaemonidae, Atyidae and Xiphocarididae) and fishes (Gobiidae and Eleotridae) consumed by the local people. The epilithic biofilm was exploited by most species, constituted an important source of autochthonous carbon and was an important source of organic matter production at the base of freshwater food webs in Caribbean rivers. Biofilm percentages in the diet reached 32% for molluscs, 85% for atyid shrimps, 29% for xiphocaridid shrimps, 14% for palaemonid shrimps and 13% for fish. Assessment of biofilm in nine rivers showed that blue and red cyanobacteria were quantitatively dominant with a moderately rich diatom flora. These results address the interactions between river biofilm and Caribbean freshwater fauna where trophic links between consumers and their potential resources have poorly been documented.
ISSN: 0969-997X

hal-00744809
https://hal.univ-antilles.fr/hal-00744809
DOI : 10.1111/j.1365-2400.2010.00767.x

Éditeur(s) : Wiley-blackwell Publishing, Inc
Résumé : Aims: A description of bacterial pathogens in shrimp ponds is necessary to understand their pathogenesis. Vibrio nigripulchritudo was shown to contain saprophytic and pathogenic strains among New Caledonian isolates. We established a method to map the development of V. nigripulchritudo in pond sediments at three different genetic levels: the species level, then at the pathogenic cluster level and finally at the plasmid level, present only in all highly pathogenic isolates. Methods and Results: PCR methods were applied to shrimp pond sediments both before and after a mortality outbreak. Using crude samples, the species V. nigripulchritudo is not detected at first (0/42 samples at day 56 post stocking) but appears frequently in the sediments after the mortality event (30/42 at day 107). The distribution of strains from the pathogenic cluster of V. nigripulchritudo also follows this pattern. In contrast, the pSFn1 virulence-associated plasmid was detected in one sample at day 56 and none at day 107. An enrichment method was developed to lower the detection limits of our assays. After enrichment, the species V. nigripulchritudo was detected in all samples at both dates. The number of samples positive for pSFn1 was 42/42 samples at day 56 and 29/42 at day 107. Conclusions: These results show that the sediments contain V. nigripulchritudo, notably pathogenic strains. Surprisingly, the virulence-associated plasmid pSFn1 found in all V. nigripulchritudo isolated from moribund shrimp appears less frequently in sediments, possibly being useless or even detrimental to its recipient bacteria in this environment. Significance and Impact of the Study: This study confirms the presence of pathogenic V. nigripulchritudo strains in shrimp pond sediment before a mortality outbreak complying with a previous hypothesis that sediments could be the infecting reservoir. After the outbreak, both total V. nigripulchritudo and pathogenic strains populations have largely increased, possibly contributing to the recurrent mortality observed in this shrimp vibriosis.
Journal Of Applied Microbiology (1364-5072) (Wiley-blackwell Publishing, Inc), 2010-06 , Vol. 108 , N. 6 , P. 2003-2011

Droits : 2010 The Society for Applied Microbiology - Wiley-Blackwell
http://archimer.ifremer.fr/doc/00004/11484/8177.pdf
DOI:10.1111/j.1365-2672.2009.04601.x
http://archimer.ifremer.fr/doc/00004/11484/

Éditeur(s) : Wiley-blackwell Publishing, Inc
Résumé : Primary production must constrain the amount of fish and invertebrates available to expanding fisheries; however the degree of limitation has only been demonstrated at regional scales to date. Here we show that phytoplanktonic primary production, estimated from an ocean-colour satellite (SeaWiFS), is related to global fisheries catches at the scale of Large Marine Ecosystems, while accounting for temperature and ecological factors such as ecosystem size and type, species richness, animal body size, and the degree and nature of fisheries exploitation. Indeed we show that global fisheries catches since 1950 have been increasingly constrained by the amount of primary production. The primary production appropriated by current global fisheries is 17-112% higher than that appropriated by sustainable fisheries. Global primary production appears to be declining, in some part due to climate variability and change, with consequences for the near future fisheries catches.
Ecology Letters (1461-023X) (Wiley-blackwell Publishing, Inc), 2010-04 , Vol. 13 , N. 4 , P. 495-505

Droits : 2010 Blackwell Publishing Ltd/CNRS
http://archimer.ifremer.fr/doc/00002/11294/7836.pdf
DOI:10.1111/j.1461-0248.2010.01443.x
http://archimer.ifremer.fr/doc/00002/11294/

Éditeur(s) : HAL CCSD Wiley-Blackwell
Résumé : International audience
Marine protist diversity inventories have largely focused on planktonic environments, while benthic protists have received relatively little attention. We therefore hypothesize that current diversity surveys have only skimmed the surface of protist diversity in marine sediments, which may harbor greater diversity than planktonic environments. We tested this by analyzing sequences of the hypervariable V4 18S rRNA from benthic and planktonic protist communities sampled in European coastal regions. Despite a similar number of OTUs in both realms, richness estimations indicated that we recovered at least 70% of the diversity in planktonic protist communities, but only 33% in benthic communities. There was also little overlap of OTUs between planktonic and benthic communities, as well as between separate benthic communities. We argue that these patterns reflect the heterogeneity and diversity of benthic habitats. A comparison of all OTUs against the Protist Ribosomal Reference database showed that a higher proportion of benthic than planktonic protist diversity is missing from public databases; similar results were obtained by comparing all OTUs against environmental references from NCBI's Short Read Archive. We suggest that the benthic realm may therefore be the world's largest reservoir of marine protist diversity, with most taxa at present undescribed.
ISSN: 0168-6496

hal-01383722
http://hal.upmc.fr/hal-01383722
http://hal.upmc.fr/hal-01383722/document
http://hal.upmc.fr/hal-01383722/file/Forster_2016_Benthic_protists.pdf
DOI : 10.1093/femsec/fiw120

Éditeur(s) : HAL CCSD Wiley
Résumé : [b]1.[/b] Plant functional traits, in particular specific leaf area (SLA), wood density and seed mass, are often good predictors of individual tree growth rates within communities. Individuals and species with high SLA, low wood density and small seeds tend to have faster growth rates.[br/][br/][b]2.[/b] If community-level relationships between traits and growth have general predictive value, then similar relationships should also be observed in analyses that integrate across taxa, biogeographic regions and environments. Such global consistency would imply that traits could serve as valuable proxies for the complex suite of factors that determine growth rate, and, therefore, could underpin a new generation of robust dynamic vegetation models. Alternatively, growth rates may depend more strongly on the local environment or growth–trait relationships may vary along environmental gradients.[br/][br/][b]3.[/b] We tested these alternative hypotheses using data on 27 352 juvenile trees, representing 278 species from 27 sites on all forested continents, and extensive functional trait data, 38% of which were obtained at the same sites at which growth was assessed. Data on potential evapotranspiration (PET), which summarizes the joint ecological effects of temperature and precipitation, were obtained from a global data base.[br/][br/][b]4.[/b] We estimated size-standardized relative height growth rates (SGR) for all species, then related them to functional traits and PET using mixed-effect models for the fastest growing species and for all species together.[br/][br/][b]5.[/b] Both the mean and 95th percentile SGR were more strongly associated with functional traits than with PET. PET was unrelated to SGR at the global scale. SGR increased with increasing SLA and decreased with increasing wood density and seed mass, but these traits explained only 3.1% of the variation in SGR. SGR–trait relationships were consistently weak across families and biogeographic zones, and over a range of tree statures. Thus, the most widely studied functional traits in plant ecology were poor predictors of tree growth over large scales.[br/][br/][b]6.[/b] Synthesis. We conclude that these functional traits alone may be unsuitable for predicting growth of trees over broad scales. Determining the functional traits that predict vital rates under specific environmental conditions may generate more insight than a monolithic global relationship can offer.
ISSN: 0022-0477

hal-01204226
https://hal.archives-ouvertes.fr/hal-01204226
DOI : 10.1111/1365-2745.12401
PRODINRA : 307144

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
ObjectivesTo compare the efficacy, in current clinical practice, of ă first regimens containing abacavir with lamivudine (ABC/3TC) or ă tenofovir with emtricitabine (TDF/FTC) in patients with baseline viral ă load 100000 HIV-1 RNA copies/mL. ă MethodsUsing a prospective cohort, we selected all patients starting a ă first HIV regimen based either on ABC/3TC or on TDF/FTC. The propensity ă score (PS) method was used to limit the indication bias due to the ă observational nature of the data. Adjusting and weighting methods via PS ă were used to compare the effectiveness of a first regimen containing ă ABC/3TC or TDF/FTC. The primary outcome was treatment failure by month ă 12 (M12). ă ResultsOverall, 2781 patients started an antiretroviral (ARV) regimen ă with ABC/3TC or TDF/FTC each in combination with efavirenz, boosted ă atazanavir or boosted darunavir. Among the 2472 uncensored patients ă before M12, 962 (39%) had a baseline viral load 100000 copies/mL of ă whom 294 were in treatment failure at or before M12. Our analyses showed ă no difference between ABC/3TC and TDF/FTC in the risk of treatment ă failure at M12 in patients starting an ARV regimen with a high viral ă load (100000 copies/mL). ă ConclusionsUsing a large prospectively collected cohort of patients ă seeking care in France, we found no evidence that ABC/3TC based regimens ă led to more failures than TDF/FTC based ones in patients with high ă baseline viral loads.
ISSN: 1464-2662

hal-01482656
https://hal.archives-ouvertes.fr/hal-01482656
DOI : 10.1111/hiv.12306

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
The easy-to-use in vivo model, zebrafish larva, is being increasingly used to screen chemical-induced hepatotoxicity, with a good predictivity for various mechanisms of liver injury. However, nothing is known about its applicability in exploring the mechanism called membrane remodeling, depicted as changes in membrane fluidity or lipid raft properties. The aim of this study was, therefore, to substantiate the zebrafish larva as a suitable in vivo model in this context. Ethanol was chosen as a prototype toxicant because it is largely described, both in hepatocyte cultures and in rodents, as capable of inducing a membrane remodeling leading to hepatocyte death and liver injury. The zebrafish larva model was demonstrated to be fully relevant as membrane remodeling was maintained even after a 1-week exposure without any adaptation as usually reported in rodents and hepatocyte cultures. It was also proven to exhibit a high sensitivity as it discriminated various levels of cytotoxicity depending on the extent of changes in membrane remodeling. In this context, its sensitivity appeared higher than that of WIF-B9 hepatic cells, which is suited for analyzing this kind of hepatotoxicity. Finally, the protection afforded by a membrane stabilizer, ursodeoxycholic acid (UDCA), or by a lipid raft disrupter, pravastatin, definitely validated zebrafish larva as a reliable model to quickly assess membrane remodeling involvement in chemical-induced hepatotoxicity. In conclusion, this model, compatible with a high throughput screening, might be adapted to seek hepatotoxicants via membrane remodeling, and also drugs targeting membrane features to propose new preventive or therapeutic strategies in chemical-induced liver diseases.
ISSN: 0260-437X

hal-01526425
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01526425
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01526425/document
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01526425/file/Zebrafish%20larva%20as%20a%20reliable%20model-Podechard%20JAT%202016%20revised.pdf
DOI : 10.1002/jat.3421

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
The paper is motivated by the long term safety analysis of the CO 2 geological storage. We present a methodology for the assessment of the ge-omechanical impact of progressive rock dissolution. The method is based on the use of X-ray tomography and the numerical dissolution technique. The influence of evolution of the microstructure on the macroscopic properties of the rock is analysed by using periodic homogenization method. The numerical computations show progressive degradation of all components of the stiffness (orthotropic) tensor. Moreover, the evolution of associated mass transfer properties (as tortuosity and conductivity tensors), by using the periodic homogenization method, is also calculated. The correlation between the mechanical parameters and the transfer properties during the dissolution pro-cess is presented. The results show that the highest increase of the hydraulic conductivity (in direction Y) is not associated with the highest decrease of Young modulus in this direction. Moreover, the highest decrease of Young modulus (in the direction X) is not associated with percolation in this direction. Finally, an incremental law to calculate settlement, in case of a rock with evolving microstructure, is proposed. The solution of the macroscopic settlement problem under constant stress and drained conditions showed that the geomechanical effects of the rock dissolution are rather limited.
ISSN: 0363-9061

hal-01104204
https://hal.archives-ouvertes.fr/hal-01104204
https://hal.archives-ouvertes.fr/hal-01104204/document
https://hal.archives-ouvertes.fr/hal-01104204/file/Numerical_computations_rock_dissolution_Wojtacki_al_2014.pdf
DOI : 10.1002/nag.2316

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
Coral bleaching events threaten coral reef habitats globally and cause severe declines of local biodiversity and productivity.Related to high sea surface temperatures (SST), bleaching events are expected to increase as a consequenceof future global warming. However, response to climate change is still uncertain as future low-latitude climatic conditionshave no present-day analogue. Sea surface temperatures during the Eocene epoch were warmer than forecastedchanges for the coming century, and distributions of corals during the Eocene may help to inform models forecastingthe future of coral reefs. We coupled contemporary and Eocene coral occurrences with information on their respectiveclimatic conditions to model the thermal niche of coral reefs and its potential response to projected climate change.We found that under the RCP8.5 climate change scenario, the global suitability for coral reefs may increase up to 16%by 2100, mostly due to improved suitability of higher latitudes. In contrast, in its current range, coral reef suitabilitymay decrease up to 46% by 2100. Reduction in thermal suitability will be most severe in biodiversity hotspots, especiallyin the Indo-Australian Archipelago. Our results suggest that many contemporary hotspots for coral reefs,including those that have been refugia in the past, spatially mismatch with future suitable areas for coral reefs posingchallenges to conservation actions under climate change.
ISSN: 1354-1013

hal-01145464
https://hal.archives-ouvertes.fr/hal-01145464
DOI : 10.1111/gcb.12868

Éditeur(s) : HAL CCSD Wiley-Blackwell
Résumé : Pervasive melting of the middle crust, as inferred in Tibet and the Altiplano, probably influences the deformation of the lithosphere. To constrain strain distribution in a pervasively molten crust, we analysed the deformation in an eroded analogue of these orogens. The Ribeira-Araçuaí orogen (SE Brazil) comprises a stack of allochthons containing large volumes of anatectic and magmatic rocks. The upper allochton (∼300 km long, 50–100 km wide and >10 km thick) involves peraluminous diatexites and leucogranites resulting from partial melting of the middle crust. It overlies another allochthon containing huge early- to syn-collisional plutons intruding metasediments. Both anatexites and magmatic intrusions display a pervasive strain-induced magmatic fabric. Homogeneous strain distribution suggests inefficient localization. U–Pb ages of ∼575 Ma imply that anatexite melting was synchronous to the early- to syn-collisional magmatism. Similarity in ages magmatic and solid-state fabrics indicates that intrusions and anatexites deformed coherently with solid-state rocks while still molten, in response to a combination of gravity-driven and collision-driven deformation.
ISSN: 0954-4879

hal-00404915
https://hal.archives-ouvertes.fr/hal-00404915
DOI : 10.1111/j.1365-3121.2007.00747.x

Éditeur(s) : HAL CCSD Wiley-Blackwell
Résumé : International audience
The Alboran Domain, situated at the western end of the Mediterranean subductionsystem, is characterized by the Ronda Peridotites, one of the world largest exposures of subcontinental mantle. Using U-Pb (LA-ICP-MS) and Ar-Ar dating, we precisely dated twotectonic events associated with the Tertiary exhumation of the Ronda Peridotites. First,shearing along the Crust-Mantle Extensional Shear Zone caused, at ca. 22.5 Ma, mantleexhumation, local partial melting in the deep crust and coeval cooling in the upper crust.Second, the Ronda Peridotites Thrust triggered the final crustal emplacement of theperidotites onto the continental crust at ca. 21 Ma, as testified by granitic intrusions in thethrust hanging-wall. The tectonic evolution of the western Alboran Domain is thereforecharacterized by a fast switch from a continental lithosphere extension in a backarc setting,with sub-continental mantle exhumation, to a rift inversion by thrusting driven by shorteningof the subduction upper plate
ISSN: 0954-4879

insu-01441962
https://hal-insu.archives-ouvertes.fr/insu-01441962
https://hal-insu.archives-ouvertes.fr/insu-01441962/document
https://hal-insu.archives-ouvertes.fr/insu-01441962/file/Frasca-TerraNova-2017.pdf
DOI : 10.1111/ter.12255

Éditeur(s) : HAL CCSD Wiley
Résumé :
How Quaternary climatic and geological disturbances influenced the composition of Neotropical forests is hotly debated. Rain fall and temperature changes during and/or immediately after the Last Glacial Maximum (LGM) are thought to have strongly affected the geographical distribution and local abundance of tree species. The paucity of the fossil records in Neotropical forests prevents a direct reconstruction of such processes. To describe community-level historical trends in forest composition, we turned therefore to inferential methods based on the reconstruction of past demographic changes. In particular, we modelled the history of rainforests in the Eastern Guiana Shield over a time scale of several thousand generations, through the application of Approximate Bayesian Computation (ABC) and Maximum Likelihood (ML) methods to diversity data at nuclear and chloroplast loci in eight species or subspecies of rainforest trees. Depending on the species and on the method applied, we detected population contraction, expansion or stability, with a general trend in favour of stability or expansion, with changes presumably having occurred during or after the LGM. These findings suggest that Guiana Shield rain forests have globally persisted, while expanding, through the Quaternary, but that different species have experienced different demographic events, with a trend towards the increase in frequency of light-demanding, disturbance-associated species.
ISSN: 0962-1083

hal-01512150
https://hal.archives-ouvertes.fr/hal-01512150
https://hal.archives-ouvertes.fr/hal-01512150/document
https://hal.archives-ouvertes.fr/hal-01512150/file/Barthe_et_al-_%7B0B6A8C5E-DDFF-4C4E-822C-4E7BC22A6C9B%7D.pdf
DOI : 10.1111/mec.13949