Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
We present GPS observations in Morocco and adjacent areas of Spain from 15 continuous (CGPS) and 31 survey-mode (SGPS) sites extending from the stable part of the Nubian plate to central Spain. We determine a robust velocity field for the W Mediterranean that we use to constrain models for the Iberia-Nubia plate boundary. South of the High Atlas Mountain system, GPS motions are consistent with Nubia plate motions from prior geodetic studies. We constrain shortening in the Atlas system to <1.5 mm/yr. 95% confidence level. North of the Atlas Mountains, the GPS velocities indicate Nubia motion with respect to Eurasia, but also a component of motion normal to the direction of Nubia-Eurasia motion, consisting of southward translation of the Rif Mountains in N Morocco at rates exceeding 5 mm/yr. This southward motion appears to be directly related to Miocene opening of the Alboran Sea. The Betic Mountain system north of the Alboran Sea is characterized by WNW motion with respect to Eurasia at 1-2 mm/yr. paralleling Nubia-Eurasia relative motion. In addition, sites located in the Betics north of the southerly moving Rif Mountains also indicate a component of southerly motion with respect to Eurasia. We interpret this as indicating that deformation associated with Nubia-Eurasia plate motion extends into the southern Betics, but also that the Betic system may be affected by the same processes that are causing southward motion of the Rif Mountains south of the Alboran Sea. Kinematic modeling indicates that plate boundary geometries that include a boundary through the Straits of Gibraltar are most compatible with the component of motion in the direction of relative plate motion, but that two additional blocks (Alboran-Rif block, Betic Mountain block), independent of both Nubia and Eurasia are needed to account for the motions of the Rif and Betic Mountains normal to the direction of relative plate motion. We speculate that the southward motions of the Alboran-Rif and Betic blocks may be related to mantle flow, possibly induced by southward rollback of the subducted Nubian plate beneath the Alboran Sea and Rif Mountains.
ISSN: 0264-3707

hal-00475538
https://hal.archives-ouvertes.fr/hal-00475538
DOI : 10.1016/j.jog.2009.10.007

Éditeur(s) : HAL CCSD
Résumé : International audience
The complexity of the Lesser Antilles vegetation must be linked to the variety of topographic features that influence the structure of some climatic parameters, particularly the rainfall. The above mentioned environmental factors influence a plurality of biotopes colonized by specific phytocenoses. Using survey transects of different minimal areas, we highlighted the specific, biocenotic, structural and architectural heterogeneity of the survey stations. This spatio-temporal differentiation of plant groupings is strongly guided by the activities of the successive human societies. These elements show that the anthropized vegetation of the Lesser Antilles represents a true laboratory for the study of plant succession using the synchronic approach.
ISSN: 2320-5407

hal-01376445
https://hal.univ-antilles.fr/hal-01376445
DOI : 10.21474/IJAR01/1322

Éditeur(s) : Elsevier Science Bv
Résumé : Shrimp aquaculture in New Caledonia is subject to seasonal mortalities during grow-out due to highly virulent Vibrio nigripulchritudo (Vn). To understand the mechanisms affecting shrimp resistance and leading to significant mortality, a shrimp ecophysiology and immunology survey was conducted on two farms, the first considered as a "control" farm (HC), the second affected by the disease (DF). Mortality observed during the survey at DF started 50 days after stocking and was typical of this disease. The main observations regarding shrimp were: (a) growth was not affected by the disease and was faster in the DF than in the HC pond; (b) disease did not affect one sex more than the other, or a specific part of the population in terms of weight; (c) the physical condition of shrimp did not specifically allow us to foresee disease outbreak; (d) shrimp at late premolt stage D-2 and early postmolt stage A appeared to be at some points of the mortalities - but not continuously - the most sensitive to disease; (e) physiological, immunological and nutritional parameters of uninfected shrimp in the DF pond were altered, suggesting that environmental stress occurred just before the first mortalities; (f) data suggest that Vn-infected shrimp are more stressed than the presumed healthy shrimp. Combined with pathological and environmental knowledge gained in parallel during this survey, a conceptual model is proposed. Results suggest that an unstable environment induced conditions (i) stressful for the shrimp, increasing their susceptibility to bacterial infections and (ii) favoring the proliferation of the pathogen in the pond. The combination of these two processes could lead to significant mortality.
Aquaculture (0044-8486) (Elsevier Science Bv), 2013-04 , Vol. 388 , P. 105-114

Droits : 2013 Elsevier B.V. All rights reserved.
http://archimer.ifremer.fr/doc/00176/28764/27567.pdf
DOI:10.1016/j.aquaculture.2013.01.010
http://archimer.ifremer.fr/doc/00176/28764/

Éditeur(s) : HAL CCSD SAGE Publications
Résumé : International audience
: French Guiana is the French territory that is most affected by HIV. AIDS incidence is much higher than in mainland France and sex work seems to be an important driver of the epidemic. The objective of this study was to describe consistent condom use among female sex workers with their clients and their intimate partners and to identify determinants of non-use of condoms. An HIV/AIDS Knowledge, Attitudes, Behaviours and Practices survey was conducted in 2009-2010 among sex workers in French Guiana. A total of 477 sex workers were interviewed. Female sex workers were more likely to use condoms with their clients (97%) than with their intimate partners (45%). The factors associated with non-consistent condom use with the intimate partner were having had an abortion, feeling at risk for HIV, not evaluating one's own risk for HIV, living as a couple, being Dominican, not feeling comfortable asking intimate partners to use condoms. Although a high proportion of female sex workers declared using condoms with commercial partners, there is still room for improvement in the prevention of transmission with both commercial and intimate partners.
ISSN: 0956-4624

inserm-01065111
http://www.hal.inserm.fr/inserm-01065111
http://www.hal.inserm.fr/inserm-01065111/document
http://www.hal.inserm.fr/inserm-01065111/file/Table_III_IJSA.pdf
http://www.hal.inserm.fr/inserm-01065111/file/2014_Parriault_-_Predictive_factorssur unprotected_sex_for_female_sex_workers.pdf

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
We explore the use of seismic noise produced by rivers to monitor the bed load transport in the case of a low-discharge braided river in the French Alps: the "torrent de St Pierre". For this purpose, we deployed two dedicated seismic networks during summers 2007 and 2008, for which the characteristics of the recorded continuous signal are similar despite changes in the sensor locations. For dry weather conditions, only melting of nearby glaciers controls the supply of water to the stream. In these conditions, the river hydrology and the seismic energy in the 2-80 Hz frequency band both follow a diurnal fluctuation similar to the thermal amplitude. In contrast during rainfall episodes, the temperature variation fails to explain the hydrodynamic changes. Dense cloud covers reduce glacier melting and the recorded seismic energy denotes bursts of high-frequency seismic noise well correlated with water level data. Comparisons between the recorded seismic signals and the collected hydrological and sediment load data indicate that a frequency band of 3-9 Hz best explains the water level changes and thus the seismic waves coming from the flow turbulence. These analyses also reveal the presence of a seismic noise threshold that might be linked to the water shear stress exerted by the flowing water. Using the seismic energy in this frequency band as a proxy of the fluvial shear stress, the seismic-hydrologic relationship may be sensitive to variations in bed load transport. The spectral content of the seismic energy shows patterns consistent with the mobilization of sediment particles. From the interpretations of the seismic wave attenuation of river sources, we finally propose that stations at a distance from the stream less than 50 m are able to record most sediment particles. Farther stations are still useful during extreme events when largest grain sizes are mobilized. More generally this study demonstrates the feasibility of using the river seismic signal to survey bed load transport in various river types from small braided mountain rivers like the "torrent de St Pierre" to the large entrenched Himalayan rivers.
ISSN: 0022-1694

hal-00644789
https://hal.archives-ouvertes.fr/hal-00644789
DOI : 10.1016/j.jhydrol.2011.07.014

Éditeur(s) : HAL CCSD Springer Verlag (Germany) Springer Verlag
Résumé : International audience
Recent mathematical calculations allow us to define set fracture intensity (I), i.e., the amount of rock mass affected by fracture sets, independently of the investigation mode. This parameter, characteristic of each rock mass, is of much interest to describe the mechanical response of the rock mass to external influences. The aim of this work is to apply these mathematical equations on one site using measurements of three distinct fracture sets: (1) on a plane surface, (2) along a scanline, and (3) using borehole imaging, in order to evaluate and explain variability in collected data. Even if the three types of measurements give differences on absolute intensity values, they still define similar trends, i.e., the order of the fracturing impact of joint sets is the same from the three measurement methods, irrespective of the fact that obtained values are quite different from one survey method to another. We discuss the possible origins of these biases.
ISSN: 1435-9529

hal-01121556
https://hal.archives-ouvertes.fr/hal-01121556
DOI : 10.1007/s10064-014-0572-1

Éditeur(s) : NRC
Résumé : Universal kriging was used to model the spatio-temporal variability in the acoustic density of tuna aggregations recorded during star echosounding surveys around moored fish aggregating devices (FADs) in Martinique (Lesser Antilles). The large-scale deterministic drift in the tuna spatial distribution was modeled using an advection-diffusion equation applied to animal grouping. Residuals from the drift were modeled as a random component with small-scale spatial correlation. An estimation variance formula was derived from this deterministic-statistical mixed model to assess the mean precision of density estimates of daytime tuna aggregation. The mean relative error obtained with our star design for daytime surveys was 24%. The methodology was applied to estimate daily maxima of tuna biomass around moored FADs during four monthly sea cruises. The daily peak of tuna biomass aggregated around moored FADs was 9 t on average (standard deviation = 4). Estimation variances for different survey designs were compared for optimizing sampling strategy.
La distribution spatiale d'agrégations de thons autour de dispositifs de concentration de poissons (DCP) ancrés a été étudiée en Martinique (Petites Antilles) au moyen de parcours acoustiques en étoile. Les densités acoustiques géoréférencées attribuées aux thons ont été analysées à l'aide d'un modèle de krigeage universel. Une tendance à large échelle a été identifiée dans la distribution spatiale des thons. Cette tendance a été modélisée de façon déterministe au moyen d'une équation d'advection–diffusion appliquée aux groupes d'animaux. Les résidus de la tendance ont été modélisés comme une composante aléatoire du modèle, spatialement corrélée à faible échelle. De ce modèle, qui contenant une composante déterministe et une composante statistique, a été déduite une formule permettant de calculer la variance d'estimation de la densité diurne moyenne de l'agrégation de thons autour des DCP. L'erreur relative moyenne commise sur l'estimation de la densité de thons lors d'un parcours en étoile diurne a été estimée à 24 %. Cette méthode a été appliquée afin d'estimer les maxima journaliers de biomasse de l'agrégation de thons observés lors de quatre campagnes en mer mensuelles successives autour des DCP ancrés. La biomasse maximale de thons agrégée autour des DCP ancrés durant une phase diurne était en moyenne de 9 t (écart type : 4). Les variances d'estimation obtenues avec différents parcours acoustiques ont été comparées afin d'optimiser la stratégie d'échantillonnage.
Canadian journal of fisheries and aquatic sciences (0706-652X) (NRC), 2008-06 , Vol. 65 , N. 6 , P. 1193-1205

Droits : 2008 National Research Council Canada
http://archimer.ifremer.fr/doc/2008/publication-4559.pdf
DOI:10.1139/F08-050
http://archimer.ifremer.fr/doc/00000/4559/

Éditeur(s) : HAL CCSD Taylor & Francis
Résumé : International audience
To analyze the characteristics and outcome of infective endocarditis (IE) according to the time interval between IE first symptoms and diagnosis.
Among the IE cases of a French population-based epidemiological survey, patients having early-diagnosed IE (diagnosis of IE within 1 month of first symptoms) were compared with those having late-diagnosed IE (diagnosis of IE more than 1 month after first symptoms).
Among the 486 definite-IE, 124 (25%) had late-diagnosed IE whereas others had early-diagnosed IE. Early-diagnosed IE were independently associated with female gender (OR = 1.8; 95% CI [1.0-3.0]), prosthetic valve (OR= 2.6; 95% CI [1.4-5.0]) and staphylococci as causative pathogen (OR = 3.7; 95% CI [2.2-6.2]). Cardiac surgery theoretical indication rates were not different between early and late-diagnosed IE (56.3% vs 58.9%), whereas valve surgery performance was lower in early-diagnosed IE (41% vs 53%; p = .03). In-hospital mortality rates were higher in early-diagnosed IE than in late-diagnosed IE (25.1% vs 16.1%; p < .001).
The time interval between IE first symptoms and diagnosis is closely related to the IE clinical presentation, patient characteristics and causative microorganism. Better prognosis reported in late-diagnosed IE may be related to a higher rate of valvular surgery. KEY MESSAGES Infective endocarditis, which time interval between first symptoms and diagnosis was less than one month, were mainly due to Staphylococcus aureus in France. Staphylococcus aureus infective endocarditis were associated with septic shock, transient ischemic attack or stroke and higher mortality rates than infective endocarditis due to other bacteria or infective endocarditis, which time interval between first symptoms and diagnosis was more than one month. Infective endocarditis, which time interval between first symptoms and diagnosis was more than one month, were accounting for one quarter of all infective endocarditis in our study and were associated with vertebral osteomyelitis and a higher rate of cardiac surgery performed for hemodynamic indication than other infective endocarditis.
ISSN: 0785-3890

hal-01509563
https://hal.archives-ouvertes.fr/hal-01509563
PUBMED : 27607562

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : We present a preliminary probabilistic tsunami hazard assessment of Canadian coastlines from local and far-field, earthquake, and large submarine landslide sources. Analyses involve published historical, palaeotsunami and palaeoseismic data, modelling, and empirical relations between fault area, earthquake magnitude, and tsunami run-up. The cumulative estimated tsunami hazard for potentially damaging run-up (≥1.5 m) of the outer Pacific coastline is ~40-80 % in 50 years, respectively one and two orders of magnitude greater than the outer Atlantic (~1-15 %) and the Arctic (<1 %). For larger run-up with significant damage potential (≥3 m), Pacific hazard is ~10-30 % in 50 years, again much larger than both the Atlantic (~1-5 %) and Arctic (<1 %). For outer Pacific coastlines, the ≥1.5 m run-up hazard is dominated by far-field subduction zones, but the probability of run-up ≥3 m is highest for local megathrust sources, particularly the Cascadia subduction zone; thrust sources further north are also significant, as illustrated by the 2012 Haida Gwaii event. For Juan de Fuca and Georgia Straits, the Cascadia megathrust dominates the hazard at both levels. Tsunami hazard on the Atlantic coastline is dominated by poorly constrained far-field subduction sources; a lesser hazard is posed by near-field continental slope failures similar to the 1929 Grand Banks event. Tsunami hazard on the Arctic coastline is poorly constrained, but is likely dominated by continental slope failures; a hypothetical earthquake source beneath the Mackenzie delta requires further study. We highlight areas susceptible to locally damaging landslide-generated tsunamis, but do not quantify the hazard.
ISSN: 0921-030X

hal-00963614
https://hal.archives-ouvertes.fr/hal-00963614
DOI : 10.1007/s11069-013-0809-5

Éditeur(s) : Public Library Science
Résumé : Estimating diversity and abundance of fish species is fundamental for understanding community structure and dynamics of coral reefs. When designing a sampling protocol, one crucial step is the choice of the most suitable sampling technique which is a compromise between the questions addressed, the available means and the precision required. The objective of this study is to compare the ability to sample reef fish communities at the same locations using two techniques based on the same stationary point count method: one using Underwater Visual Census (UVC) and the other rotating video (STAVIRO). UVC and STAVIRO observations were carried out on the exact same 26 points on the reef slope of an intermediate reef and the associated inner barrier reefs. STAVIRO systems were always deployed 30 min to 1 hour after UVC and set exactly at the same place. Our study shows that; (i) fish community observations by UVC and STAVIRO differed significantly; (ii) species richness and density of large species were not significantly different between techniques; (iii) species richness and density of small species were higher for UVC; (iv) density of fished species was higher for STAVIRO and (v) only UVC detected significant differences in fish assemblage structure across reef type at the spatial scale studied. We recommend that the two techniques should be used in a complementary way to survey a large area within a short period of time. UVC may census reef fish within complex habitats or in very shallow areas such as reef flat whereas STAVIRO would enable carrying out a large number of stations focused on large and diver-averse species, particularly in the areas not covered by UVC due to time and depth constraints. This methodology would considerably increase the spatial coverage and replication level of fish monitoring surveys.
Plos One (1932-6203) (Public Library Science), 2014-01 , Vol. 9 , N. 1 , P. -

Droits : 2014 Mallet et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
http://archimer.ifremer.fr/doc/00170/28132/26352.pdf
DOI:10.1371/journal.pone.0084344
http://archimer.ifremer.fr/doc/00170/28132/

Éditeur(s) : HAL CCSD
Résumé : International audience
The "South-Dominica" archaeological mission of the French ministry of foreign affairs has started work in 2005. Designed to enlighten the archaeological terra incognita dominicana, this research has essentially been dedicated to the early ceramic occupation of the island. Our work has been based on the analysis of the few collections already existing, on systematic survey campaigns and on an important test pit program. This lecture will be concentrating on the presentation of the Soufrière site excavation. The Soufriere site, found in the seventies, is composed of an important early cedrosan saladoid occupation covered by volcanic deposits. The data obtained during this excavation, associated with other results of the "South Dominica" archaeological mission, incites us to think about a revision of the territories associated to the complexes in the Lesser Antilles.
La mission archéologique "Sud-Dominique" du ministère français des affaires étrangères a débuté ses travaux en 2005. Destinées à en finir avec la terra incognita dominicana archéologique, ces recherches sont essentiellement consacrées à l'étude du premier peuplement agro-céramique de l'île. Le travail de la mission archéologique repose sur l'étude de séries anciennes, des campagnes de prospections systématiques et un important programme de sondages. Notre présentation se concentrera sur la fouille que nous avons menée du site de Soufrière dans le sud de la Dominique. Ce gisement identifié dans les années 1970 correspond à une importante occupation saladoïde cedrosane ancienne qui a été recouverte par des dépôts volcaniques. Les données obtenues lors de cette fouille associées à l'ensemble des résultats obtenus en 3 années par la mission archéologique Sud-Dominique nous incitent à nous interroger sur la nécessité d'une révision des territoires associés à la notion de complexe dans les Petites Antilles.
XXII Conference of the International Association of Caribbean Archaeology
Kingston, Jamaica

Droits : info:eu-repo/semantics/OpenAccess
hal-00961335
https://hal.univ-antilles.fr/hal-00961335
https://hal.univ-antilles.fr/hal-00961335/document
https://hal.univ-antilles.fr/hal-00961335/file/soufriA_repaperfinal.pdf

Éditeur(s) : HAL CCSD Wiley
Résumé :  
The complex structure of tree bark reflects its many functions, which include structural support as well as defence against fire, pests and pathogens. Thick bark, however, might limit respiration by the living tissues of the trunk. Nevertheless, little research has addressed community-level variation in bark thickness, and to the best of our knowledge, no one has tested multiple hypotheses to explain variation in bark thickness. We conducted an extensive survey of bark thickness within and among species of trees in the tropical rain forests of French Guiana. Trunk bark thickness increased by 1.2 mm per 10 cm increase in stem diameter, and varied widely at all taxonomic levels. Mean trunk bark thickness was 4.5 mm (range: 0.5-29 mm), which was less that found in two Amazonian rain forests in previous studies. This survey of bark thickness should be of use for forest management since tree survival through fire is strongly predicted by bark thickness. We combined the survey data with multiple datasets to test several functional hypotheses proposed to explain variation in bark thickness. We found bark to provide an average of 10% of the flexural rigidity of tree stems, which was substantially less than that found in the only other study of bark stiffness. Bark thickness was uncorrelated with species' association with fire-prone habitats, suggesting that the influence of fire on bark thickness does not extend into moist Forests. There was also little evidence that bark thickness is affected by its function as a defence against herbivory. Nor was there evidence that thick bark limits trunk respiration. A re-analysis of previously collected anatomical data indicated that variation in rhytidome (non-conducting outer bark) thickness explains much of the variation in overall bark thickness. As rhytidome is primarily involved in protecting the living tissues of the trunk, we suggest that bark thickness is driven mostly by its defensive function. Functional explanations for the variation in bark thickness were not clear-cut. Nevertheless, this study provides a foundation for further investigation of the functional bases of bark in tropical trees.
ISSN: 0269-8463

hal-01032124
https://hal.archives-ouvertes.fr/hal-01032124
DOI : 10.1111/j.1365-2435.2010.01736.x

Éditeur(s) : HAL CCSD Springer Verlag
Résumé : In this paper, we investigate the impact of ambient temperature changes on the gravity reading of spring-based relative gravimeters. Controlled heating experiments using two Scintrex CG5 gravimeters allowed us to determine a linear correlation (R2> 0.9) between ambient temperature and gravity variations. The relation is stable and constant for the two CG5 we used: −5 nm/s2/∘C. A linear relation is also seen between gravity and residual sensor temperature variations (R2> 0.75), but contrary to ambient temperature, this relation is neither constant over time nor similar between the two instruments. The linear correction of ambient temperature on the controlled heating time series reduced the standard deviation at least by a factor of 2, to less than 10 nm/s2. The laboratory results allowed for reprocessing the data gathered on a field survey that originally aimed to characterize local hydrological heterogeneities on a karstic area. The correction of two years of monthly CG5 measurements from ambient temperature variations halved the standard deviation (from 62 to 32 nm/s2) and led us to a better hydrological interpretation. Although the origin of this effect is uncertain, we suggest that an imperfect control of the sensor temperature may be involved, as well as a change of the properties of an electronic component.
ISSN: 0949-7714

hal-01526952
https://hal.archives-ouvertes.fr/hal-01526952
DOI : 10.1007/s00190-016-0961-2

Éditeur(s) : HAL CCSD
Résumé : This thesis falls within the scope of social and human geography and more exactly of« disability studies ». Understanding the disability like a « social object », the thesis analyzes the societal consideration of disabled people in non-urbanized areas with a high issue of touristic, recreational and patrimonial development. In the first place, it's the recent construction of disability as a social object that is discussed by reminding the history of the societal consideration of the disabled person in our occidental world. The French model and his fundamental rule of global accessibility for ail the domains of the social life are explained and the « Nature and Disability » thematic is more precisely analyzed as a development of an active living ideal for people who are in a disability situation. Secondly, the thesis develops this thematic on the particular field of the Reunion Island and tries to answer to a question which is both simple and complicated: « Today, how we live with a disability on the Reunion Island? ». ln a last time and on the basis of this study of the disability inside a Reunion Island society with accelerated transformations, the thesis specifies the current tendencies with the emergence of new public policies for the welcome of disabled people on natural and touristic areas of the island. To conclude and referring to an original survey, the thesis suggests some tools of evaluation and decision-making aids to these areas.
Cette thèse s'inscrit dans le champ de la géographie humaine et sociale et plus précisément dans celui des « disability studies ». En positionnant le handicap comme une « figure du social », la thèse analyse la prise en compte sociétale des personnes à mobilité réduite (PMR) dans des environnements non urbanisés, à très fort enjeu de développement touristique, récréatif et patrimonial. Dans un premier temps, c'est la construction récente du handicap en tant que figure du social qui est abordée, en rappelant l'historique de la considération de la personne handicapée dans nos sociétés occidentales. Le modèle français et son principe fondamental d'accessibilité généralisée à tous les domaines de la vie sociale sont détaillés et la thématique « Nature et Handicap » est analysée plus précisément, en tant que développement d'un idéal de vie active pour les personnes en situation de handicap. Dans un second temps, la thèse développe cette thématique sur le terrain particulier de l'Île de La Réunion et tente de répondre à une question à la fois simple et complexe : « comment vit-on avec une déficience aujourd'hui à La Réunion ? ». Dans un dernier temps et sur la base de cette analyse du handicap au sein d'une société réunionnaise aux mutations accélérées, la thèse précise les tendances actuelles avec l'apparition de nouvelles politiques publiques d'accueil des PMR dans les espaces naturels et touristiques de l'île. S'appuyant sur une enquête originale, la thèse propose enfin des outils d'évaluation et d'aide à la décision spécifiques à ces espaces.
https://tel.archives-ouvertes.fr/tel-01279042

NNT : 2012LARE0025
tel-01279042
https://tel.archives-ouvertes.fr/tel-01279042
https://tel.archives-ouvertes.fr/tel-01279042/document
https://tel.archives-ouvertes.fr/tel-01279042/file/2012lare0025_AGuenat.pdf

Éditeur(s) : Elsevier Science Bv
Résumé : In tropical shrimp ponds, the increasing of feed input, concomitantly with the stocking shrimp biomass, induces an eutrophication of the ecosystem. Although difficult to maintain, its stability is required to guarantee the success of the culture. A 110-day period of phytoplankton and bacterioplankton stock and dynamics in an earthen pond (1.2 ha area, 1 m depth) was monitored using flow cytometry to provide baseline information on community characteristics and ecosystem instability. Seven autotrophic cell types were identified over the whole sampling period. Prokaryotic cells included Synechococcus sp., a group named UNK which presented an atypical new flow cytometric signature and picoeukaryotes (PEUK). Nanophytoplankton cells were represented by 4 groups: NAN1, NAN2, NAN3 and Cryptophytes. During the first part of the survey, picophytoplankton dominated the phytoplanktonic assemblage. The mean abundance of total cells (up to 8 x 10(6) cells mL(-1)) was among the highest recorded in marine and brackish waters. Bacterial abundance and production ranged from 0.8 to 5.1 x 10(7) cells mL(-1) and from 30 to 110 mu g C L-1 h(-1). A shift from pico to nanophytoplankton abundance was observed for a few days from d 96. During this period, heterotrophic bacteria production and abundance suddenly dropped, implying a change in the functioning of the microbial loop. This shift was concomitant with a significant shrimp mortality outbreak due to Vibrio penaeicida, the etiological agent of a disease known as Syndrome 93, which affects the shrimp industry in New Caledonia. This survey suggests that flow cytometric analysis could be used for the monitoring of aquaculture systems to improve our understanding of the complex phytoplankton and bacterial dynamics of these systems and its potential influence on disease development. (c) 2010 Elsevier B.V. All rights reserved.
Aquaculture (0044-8486) (Elsevier Science Bv), 2010-12 , Vol. 310 , N. 1-2 , P. 112-121

Droits : 2010 Elsevier B.V. All rights reserved.
http://archimer.ifremer.fr/doc/00029/14068/11312.pdf
DOI:10.1016/j.aquaculture.2010.10.022
http://archimer.ifremer.fr/doc/00029/14068/

Éditeur(s) : HAL CCSD Oxford University Press (OUP)
Résumé : International audience
This study aims to describe current risk management practices and policies across the world in relation to personal exposures from devices emitting radiofrequency fields, environmental exposures from fixed installations and exposures in the work environment. Data from 86 countries representing all WHO regions were collected through a survey. The majority of countries (76.8 %) had set exposure limits for mobile devices, almost all (90.7 %) had set public exposure limits for fixed installations and 76.5 % had specified exposure limits for personnel in occupational settings. A number of other policies had been implemented at the national level, ranging from information provisions on how to reduce personal exposures and restrictions of usage for certain populations, such as children or pregnant women to prevention of access around base stations. This study suggests that countries with higher mobile subscriptions tend to have set radiofrequency exposure limits for mobile devices and to have provisions on exposure measurements about fixed installations.
ISSN: 0144-8420

hal-01146847
https://hal-univ-rennes1.archives-ouvertes.fr/hal-01146847
DOI : 10.1093/rpd/ncu324
PUBMED : 25394650

Résumé : Since 2000, the exploitation of the deep demersal fish (200-700 m) with the use of electric winches has been increasing in Reunion island ; and this has needed a new appraisal of yields (CPUE) and individual fish sizes, as indicators of the state of the fish stocks. A first survey has been carried out at the first half of 2011, in order to set up the comparison with a previous survey in 2000 on the West coast of Reunion island. Drops of yields and sizes could be pointed out, attesting the overexploitation of the commercial species (Fleury et al 2011). This present report displays the results of a second campaign, carried out in the second half of 2011 all around the island. 32 fishing trips have been conducted which have permitted 251 fishing operations. The overexploitation (i.e. decreasing of yields and fish sizes) has been confirmed in the West of the island, and in a lower stage in the North. Yields are better in the East and the South. As much as in the first survey, the small non commercial sharks (Squalus megalops) could be countered for half of the catches. At the same time, 2 hook sizes have been tested and the small hooks have displayed a better efficiency in number of catches but not in global weight. Various types of bait have been tested and meat of small local pelagic fish (Selar crumenophtalmus and Decapterus macarellus) have appeared to be the most efficient. This report provides helpful indicators for the management of fish stocks which have been poorly surveyed and poorly regulated till now.
Depuis 2000, la pêche aux poissons démersaux profonds (200-700 m) à l'aide de virelignes électriques s'est développée à La Réunion ; et le besoin se faisait sentir d'une évaluation des rendements (CPUE) et des tailles individuelles de capture, indicateurs halieutiques classiques des états de stocks. Une première campagne a été réalisée au 1er semestre 2011 pour établir la comparaison avec une campagne de prospection réalisée en 2000 dans l'ouest de La Réunion. Elle a mis en évidence des baisses marquées des rendements et des tailles de capture, signes d’une surexploitation des espèces commerciales (Fleury et al 2011). Ce rapport présente les résultats d'une 2e campagne de prospection étendue à tout le tour de l'île. 32 marées ont été réalisées permettant la mise à l'eau de 251 filages. La surpêche (baisse des rendements et des tailles de poisson) est confirmée dans l'ouest et à un moindre degré sur la côte nord. Les rendements sont meilleurs dans l'est et le sud. Comme dans la première campagne, les requins zépines (Squalus megalops), non commercialisés à La Réunion, représentent la moitié des captures. Parallèlement, 2 tailles d'hameçons ont été comparées et les petits hameçons ont donné une augmentation du nombre de captures, mais pas du poids global. Des comparaisons ont aussi porté sur les types d'appât et les laizes de petits pélagiques locaux (pêche-cavale et bancloche) se sont révèlées les plus efficaces. Ce rapport fournit des indicateurs utiles à la gestion de stocks jusqu'ici peu suivis, et peu encadrés.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/00089/20048/18049.pdf
http://archimer.ifremer.fr/doc/00089/20048/

Éditeur(s) : Cushman Foundation for Foraminiferal Research
Résumé : Large populations of the living benthic foraminifera Quinqueloculina carinatastriata (Wiesner, 1923) are reported for the first time from intertidal mudflats of the French Atlantic coast (Marennes-Oléron Bay and Ile de Ré). Maximum abundance of living specimens was recorded in early autumn. The species was previously described from the Adriatic and Tyrrhenian Seas (central Mediterranean Sea) and reported from the Eastern Mediterranean and Red Seas, as well as tropical and subtropical regions. A survey of available literature to trace records of the species in muddy shallow habitats along the western coasts of Europe and Africa reveals that the species is unrecorded from the Western Mediterranean Sea and is unknown in the eastern Atlantic Ocean from the Ivory Coast to Denmark, including the British Isles. This supports the hypothesis that the species has been accidentally introduced outside its natural range as a probable result of mariculture trade and/or shipping activities. This is the first report of a successful introduction of a non-indigenous benthic foraminifera to the Atlantic coast of Europe.
The Journal of Foraminiferal Research (0096-1191) (Cushman Foundation for Foraminiferal Research), 2007-07 , Vol. 37 , N. 3 , P. 204-212

Droits : Cushman Foundation for Foraminiferal Research
http://archimer.ifremer.fr/doc/2007/publication-2587.pdf
DOI:10.2113/gsjfr.37.3.204
http://archimer.ifremer.fr/doc/00000/2587/

Éditeur(s) : HAL CCSD
Résumé : The strong earthquake (M = 6.3) occurred on 21st November 2004 in the DominicaPassage, between Guadeloupe and Dominica (Lesser Antilles), generated aweak tsunami with maximum amplitude 80 cm on neighbouring islands. Field surveyis conducted on November 27, 2004. Data of the field survey are described. Results ofthe numerical simulations in the framework of the shallow-water theory are in reasonableagreement with observed data.
European Geosciences Union - General Assembly 2005
Vienne, Austria

hal-00090423
https://hal.archives-ouvertes.fr/hal-00090423

Éditeur(s) : HAL CCSD Wiley Open Access
Résumé : International audience
Coral disease outbreaks have increased over the last three decades, but their causal agents remain mostly unclear (e.g., bacteria, viruses, fungi, protists). This study details a 14-month-long survey of coral colonies in which observations of the development of disease was observed in nearly half of the sampled colonies. A bimonthly qPCR method was used to quantitatively and qualitatively evaluate Symbiodinium assemblages of tagged colonies, and to detect the presence of Vibrio spp. Firstly, our data showed that predisposition to disease development in general, and, more specifically, infection by Vibrio spp. in Acropora cytherea depended on which clades of Symbiodinium were harbored. In both cases, harboring clade D rather than A was beneficial to the coral host. Secondly, the detection of Vibrio spp. in only colonies that developed disease strongly suggests opportunistic traits of the bacteria. Finally, even if sporadic cases of switching and probably shuffling were observed, this long-term survey does not suggest specific-clade recruitment in response to stressors. Altogether, our results demonstrate that the fitness of the coral holobiont depends on its initial consortium of Symbiodinium, which is distinct among colonies, rather than a temporary adaptation achieved through acquiring different Symbiodinium clades.
ISSN: 2045-7758

hal-01346931
https://hal-uvsq.archives-ouvertes.fr/hal-01346931
https://hal-uvsq.archives-ouvertes.fr/hal-01346931/document
https://hal-uvsq.archives-ouvertes.fr/hal-01346931/file/2016%20Rouze%20EcolEvol.pdf
DOI : 10.1002/ece3.1895