Éditeur(s) : HAL CCSD
Résumé : 1 p.
For groundwater issues (potential leakages in waste repository, aquifer management ...), the development of modeling techniques is far ahead of the actual knowledge of aquifers. This raises two fundamental issues: 1) which and how much data are necessary to make predictions accurate enough for aquifer management issues; 2) which models remain relevant to describe the heterogeneity and complexity of geological systems. The French observatory H+ was created in 2002 with the twofold motivation of acquiring a large database for validating models of heterogeneous aquifers, and of surveying groundwater quality evolution in the context of environmental changes. H+ is a network of 4 sites (Ploemeur, Brittany, France; HES Poitiers, France; Cadarache, France; Campos, Mallorca, Spain) with different geological, climatic, and economic contexts. All of them are characterized by a highly heterogeneous structure (fractured crystalline basement for Ploemeur, karstified and fractured limestone for Poitiers, Cadarache and Mallorca), which is far to be taken into account by basic models. Ploemeur is exploited as a tap-water plant for a medium-size coastal city (15,000 inhabitants) for 20 years. Each site is developed for long term investigation and monitoring. They involves a dense network of boreholes, detailed geological and geophysical surveys, periodic campaigns and/or permanent measurements of groundwater flow, water chemistry, geophysical signals (including ground motions), climatic parameter, etc. Several large-scale flow experiments are scheduled per year to investigate the aquifer structure with combined geophysical, hydrogeological, and geochemical instruments. All this information is recorded in a database that has been developed to improve the sustainability and quality of data, and to be used as a collaborative tool for both site researchers and modelers. This project lasts now for 5 years. It is a short time to collect the amount of information necessary to apprehend the complexity of aquifers; but it is already enough to obtain a few important scientific results about the very nature of the flow heterogeneity, the origin and residence time of water elements, the kinetic of geochemical processes, etc. We have also developed new methods to investigate aquifers (in-situ flow measurements, flow experiment designs, groundwater dating, versatile in-situ probes, etc.). This experience aiming at building up long term knowledge appears extremely useful to address critical issues related to groundwater aquifers: the structure and occurrence of productive aquifer in crystalline basement, the assessment of aquifer protection area in the context of highly heterogeneous flow, the biochemical reactivity processes, the long term evolution of both water quantity and quality in the context of significant environmental changes, for instance.
AGU, Fall Meeting 2008
San Francisco, United States

insu-00375980
https://hal-insu.archives-ouvertes.fr/insu-00375980

Éditeur(s) : HAL CCSD Wiley
Résumé : International audience
This paper describes how to tackle new challenging coastal engineering problems related to beach erosion with a shape optimization approach. The method modifies the shape of the sea bottom in order to reduce beach erosion effects. Global optimization is shown to be necessary as the related functionals have several local minima. We describe the physical model used, the proposed protection devices against beach erosion and real case applications.
ISSN: 0029-5981

hal-00411912
https://hal.archives-ouvertes.fr/hal-00411912
DOI : 10.1002/nme.2209

Résumé : The current legal regime governing marine farms reflects what French shellfish culture used to be: an artisanal, traditional and family activity. Even if this profession is of social importance, it has never really been taken into account in coastal management decisions. This is the reason why, if aquaculture must expand, the whole related legal regime has to be adapted to the new needs of a profession which is still trying to find itself. New links will develop with the responsible authorities. Conflicts of a new type will rise between the different coastal and marine space users. A rethinking of the standard public property regulations seems necessary.
Le régime juridique actuel des élevages marins est le reflet de ce qu'a été la conchyliculture en France : une activité artisanale, traditionnelle et familiale. Socialement importante, cette profession n'a cependant pas pesé lourd dans les choix d'aménagement du littoral. C'est pourquoi, si l'aquaculture doit prendre désormais de l'extension, c'est l'ensemble du régime juridique qui lui est applicable qu'il convient d'adapter aux besoins nouveaux d'une profession qui se cherche. Des rapports nouveaux vont naître avec 1'Administration de tutelle. Des conflits d'un type particulier risquent de surgir entre les divers usagers de l'espace marin et littoral. Un réaménagement des règles classiques de la domanialité publique semble inévitable. [OCR NON CONTRÔLE]

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/1983/rapport-4804.PDF
http://archimer.ifremer.fr/doc/00000/4804/

Éditeur(s) : HAL CCSD
Résumé : International audience
After defining the High Performance Pre- Computing --referred as HPPC-- concept, the aim of the present study is to develop a prototype whether to approve or not the benefits of this concept. Our application case tries to answer the geophysical issue of coastal flooding. This is an example of an alert system based on the HPPC architecture, thus on pre-computed scenarios. The prototype provides the scientists with an ergonomic and on-demand tool allowing the run of scenarios of any implemented numerical models. These runs are available through a web application which submits the corresponding jobs on the remote french public cluster of HPC@LR. In this study we simulate the waves propagation over a Mediterranean grid using the wave model WaveWatch III⃝R . A reference simulation using usual conditions is approximated using the k-NN algorithm over 12, 98 and then 980 pre-computed scenarios. This simple experiment demonstrates how useful the pre-computing of scenarios is for alert systems as far as enough and relevant scenarios are pre-computed. This is the reason why searches continue in each critical points of the HPPC architecture such as the design of experiment, the approximation of the results by meta-models and the research of the closest scenarios in this big data context.
4th International Conference on Knowledge and Systems Engineering
Danang, Vietnam

lirmm-00736797
https://hal-lirmm.ccsd.cnrs.fr/lirmm-00736797
https://hal-lirmm.ccsd.cnrs.fr/lirmm-00736797/document
https://hal-lirmm.ccsd.cnrs.fr/lirmm-00736797/file/PID2396685.pdf
DOI : 10.1109/KSE.2012.36

Éditeur(s) : Edp Sciences S A
Résumé : Moored FADs (MFADs) have been a key area for development in Guadeloupe (Lesser Antilles) since the late 1980's. The main objectives underpinning the development of MFADs were to (i) reduce fishing pressure on coastal fishing resources; (ii) boost fishermen's incomes; and (iii) increase local consumption of locally generated fishery products as a proportion of overall consumption. This paper gives an overview of the current structure of Guadeloupe's fishing fleet and fisheries, with a specific focus on MFAD fleets in a relatively unstructured environment with regard to regulation, and so how these fleets operate in a context of unrestricted development of private MFADs. In addressing the following key issues, this paper aims to: assess the economic performance of fleets operating on MFADs, understand why the MFAD fishing activity has not developed more than it has, and suggest how better MFAD management could improve the situation. Socio-economic information on a trip and fleet level basis were collected and stored on a fisheries information system to analyse the relative attractiveness of MFAD fishing and assess the overall economic performance of MFAD fleets as compared to other non-MFAD fleets. Non-monetary variables were also tested to explain the degree of dependence on MFADs. In 2008, economic returns from FADs were relatively low, both in terms of wages for the crews and in terms of profit for vessel owners. Earnings were higher than coastal fishing activities, but seem to have been very sensitive to the indicators used in our analysis. MFADs are expected to become much more attractive as a result of MFAD regulation, especially through the establishment of collective MFADs.
Aquatic Living Resources (0990-7440) (Edp Sciences S A), 2013-01 , Vol. 26 , N. 1 , P. 97-105

Droits : EDP Sciences, IFREMER, IRD 2013
http://archimer.ifremer.fr/doc/00137/24836/22914.pdf
DOI:10.1051/alr/20013044
http://archimer.ifremer.fr/doc/00137/24836/

Éditeur(s) : Université de Bretagne Occidentale
Résumé : This activity report entitled (“Chemical contamination of the marine environment: from measurement to risk assessment”) summarizes the main stages my career at Ifremer from November 1975 to june 2013. The first chapter deals with the seawater chlorination and chlorinated waters released into the sea, the identification and the conditions of the formation of various by-product of these processes. The second chapter concerns PCBs, their nature, their chemical analysis in environmental matrices. PCBs are considered as the best examples of persistant and bioaccumulable compounds and therefore, in all this report they are flagship contaminants to which other groups of studied substances are compared. The third chapter refers to studies performed within marine pollution monitoring programme RNO (Réseau National d’Observation de la qualité de l’environnement marin - National observation network on the quality of the marine environnment) and well as other more limited studies like a first assessement on the presence of dioxins and dioxin-like PCBs in the French coastal marine environment and last, on the use of zebra mussel (Dresseinia polymorpha) as sentinelle species of the chemical contamination in the Seine estuary. The next two chapters are about bioaccumulation and about the distribution of organic contaminants (PCBs, dioxins, PAHs, PBDEs) in marine organisms and in marine foodwebs. These studies aim at a better knowledge of the presence and fate of these compounds in fish and marine organisms eitheir in an environmental perspective (chapter IV) or in order to contribute to the assessment of their health impact, or more precisely to estimate therelative part of fish and seafood to the human exposure to chemical residues (chapter V). To conclude, the chapter VI concerns the PCB and dioxin fingerprints in the various studied marine matrices ; analytical and environmental interpretations of the observed differences are suggested as well as possible applications.
Ce bilan d’activité intitulé « Contamination chimique du milieu marin : de la mesure à l’évaluation des risques » retrace les étapes essentielles de mon parcours à Ifremer entre novembre 1975 et juin 2013. Le premier chapitre traite de la chloration dans l’eau de mer et les rejets chlorés en mer, l’identification des sous-produits formés lors de ces traitements, les conditions de leur formation. Le second chapitre concerne la nature des PCB et leur analyse dans les matrices environnementales. Les PCB considérés comme les meilleurs exemples de composés persistants bioaccumulables constituent les « contaminants phares » de l’ensemble de ce travail et c’est par rapport aux PCB que sont comparés et évalués les autres groupes de contaminants étudiés. Le troisième chapitre se rapporte aux travaux réalisés dans le cadre de la surveillance RNO (Réseau National d’Observation de la qualité de l’environnement marin) ainsi que dans des études ponctuelles comme un premier inventaire sur les niveaux de présence des dioxines (PCDD et PCDF) dans l’environnement marin littoral ou sur l’utilisation de la moule zébrée (Dresseinia polymorpha) comme espèce indicatrice de la contamination de l’estuaire de la Seine. Les deux chapitres suivants sont consacrés aux travaux sur la bioaccumulation et aux contaminants organiques (PCB, dioxines, HAP, PBDE) dans les organismes et les réseaux trophiques marins soit dans une perspective environnementale sur le devenir des contaminants dans le vivant (chapitre IV) soit dans le cadre de l’évaluation des risques sanitaires ou, plus précisément, de l’estimation de la contribution de la consommation des produits de la mer à l’exposition de l’homme aux résidus chimiques (chapitre V). Pour terminer, le chapitre VI concerne les empreintes de PCB et de dioxines dans les différentes matrices étudiées ; une interprétation analytique et environnementale des différences observées est proposée ainsi que de possibles applications.

Droits : 2013 UBO
http://archimer.ifremer.fr/doc/00168/27946/26237.pdf
http://archimer.ifremer.fr/doc/00168/27946/

Résumé : The maritime economy includes the activities linked to the sea, namely: - Marine resource extraction: living resources and marine minerals, - Exploitation of marine space and of physical properties of marine waters (energy plants - using marine water as a heat sink, marine renewable energies, submarine cable laying, - maritime and coastal construction and public works, maritime transport, Navy), - Exploitation of seascapes (tourism, leisure, boating), - Resource processing (of living resources and oil & gas) - Manufacturing and service industries supplying the above exploitation activities: shipbuilding, ship repair and boat building and their suppliers, oil and gas services, financial services, - Public services: defence; State intervention at sea and public services to maritime activities and to seafarers; public and private activities contributing to the protection of marine and coastal environment; and public research. Since 1997, the French Marine Economic Data report, published by Ifremer, includes a set of key sectoral indicators used to value the economic significance of the French marine-related activities in terms of production and jobs, their role in the national economy, their weight in international competition and the importance of non-market public services. The analysis of the marine sectors is carried out mainly at national scale but regional indicators are also presented when they are available. The European dimension of the activities is also taken into account.

Droits : 2014 Ifremer
http://archimer.ifremer.fr/doc/00253/36455/34990.pdf
DOI:10.13155/36455
http://archimer.ifremer.fr/doc/00253/36455/

Éditeur(s) : HAL CCSD Public Library of Science
Résumé : International audience
As environmental sounds are used by larval fish and crustaceans to locate and orientate towards habitat during settlement, variations in the acoustic signature produced by habitats could provide valuable information about habitat quality, helping larvae to differentiate between potential settlement sites. However, very little is known about how acoustic signatures differ between proximate habitats. This study described within-and between-site differences in the sound spectra of five contiguous habitats at Moorea Island, French Polynesia: the inner reef crest, the barrier reef, the fringing reef, a pass and a coastal mangrove forest. Habitats with coral (inner, barrier and fringing reefs) were characterized by a similar sound spectrum with average intensities ranging from 70 to 78 dB re 1μPa.Hz-1. The
ISSN: 1932-6203

hal-01211705
https://hal-univ-perp.archives-ouvertes.fr/hal-01211705
https://hal-univ-perp.archives-ouvertes.fr/hal-01211705/document
https://hal-univ-perp.archives-ouvertes.fr/hal-01211705/file/journal.pone.0135733.pdf
DOI : 10.1371/journal.pone.0135733

Éditeur(s) : HAL CCSD Oxford University Press (OUP)
Résumé : International audience
Ocean loading effects cause 3-D displacements large enough to affect space geodesy measurements either at the subdiurnal periods or at longer time scales by the means of spurious signals. GPS measurements, in turn, could provide local improvements of the models in coastal areas if their ability to precisely monitor such rapid displacements is assessed. In this paper, we use 105 days of continuous GPS measurements collected in 2004 in the French Brittany and Cotentin region to investigate: (1) the precision achieved by the GPS analysis on measuring 3-D subdiurnal displacements and amplitude and phase of the tidal constituents, (2) the quality of the most recent ocean tide model FES2004 in such a complex coastal context. Indeed, in this area, tide amplitudes are among the largest in the world (up to 16 cm of loading displacements on the vertical component) and are believed to show strong shallow-water tides. From a state of the art GPS analysis using the scientific GAMIT software over 2-h sessions, we test two independent strategies for the realization of the reference frame. The position time series are then compared with the displacements predicted by the FES2004 model applied on an elastic Earth model. The two sets of results are consistent with each other at the same level of agreement than with the predicted displacements, namely 3–5 mm on the horizontal components, 10 mm on the vertical. This assesses the capability of this technique for measuring 3-D ocean tide loading deformation. We validate the FES2004 model in the Brittany area, even though it slightly (2–7 mm) underestimates the three components amplitudes. With a harmonic analysis of the observed position time series, we obtain nevertheless an agreement at a submillimetre level for the M2, N2, O1, Q1 tidal constituents and at a millimetre level for the K1 and S2 tidal constituents. Moreover, we can extract a significant M4 load signal at the 95 per cent confidence level from the GPS time series at the stations located in the Mont St Michel area. The detection of other shallow-water constituents would be helpful to understand the amplitude deficit between the FES2004 predicted and GPS observed displacements.
ISSN: 0956-540X

insu-00335909
https://hal-insu.archives-ouvertes.fr/insu-00335909
https://hal-insu.archives-ouvertes.fr/insu-00335909/document
https://hal-insu.archives-ouvertes.fr/insu-00335909/file/Vergnolle_GJI_08_revised.pdf
DOI : 10.1111/j.1365-246X.2008.03734.x

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : L’algue est une ressource marine peu étudiée par la géographie ; elle offre pourtant des potentialités de développement économique. Les macro-algues cultivées à des fins alimentaires sont une alternative à la pêche. Les micro-algues constituent une biomasse valorisable : molécule pharmaceutique, Oméga 3 et biocarburants. De ces différents usages naît la question suivante : les algues sont-elles une ressource marine à exploiter pour développer durablement les territoires de la zone intertropicale ? Nous présenterons tout d’abord l’algoculture à l’échelle mondiale en soulignant le faible poids de cette activité dans le bassin caribéen. Puis nous montrerons que l’algoculture s’inscrit dans un processus de développement durable en assurant un revenu à des communautés rurales (Petites Antilles). Enfin, dans une approche comparative (États-Unis), nous verrons que l’espace caribéen est une région de projets et d’aménagements durables qui a des atouts pour développer l’algoculture : exposition solaire, hautes températures, proximité de la recherche américaine.
Algae as sea resource have not been largely explored in Geography, yet it offers the potential for economic development. Macro-algae are cultivated for food purposes and they can substitute for fishing. Micro-algae can be valued as biomass: “nutraceutics”, Omega 3, biofuel. These various utilizations raise a question: are algae a key to a sustainable development in intertropical islands? We shall present Algaculture on a global scale, while emphasizing its low importance in the Caribbean. Then we shall show how algaculture can be part of a process of sustainable development by providing revenue to rural communities (Lesser Antilles). Finally, in a comparative approach (with the US), we shall see that the Caribbean Region has a number of assets for algaculture that make it suitable for sustainable projects and infrastructures: solar exposure, high temperatures, close to the US research centers.
États-Unis
Caraïbes

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.4389
http://journals.openedition.org/etudescaribeennes/4389

Éditeur(s) : Yale University
Résumé : Data from a hydrographic section carried out in January-March 1994 offshore from the eastern coast of South America from 50S to 10N, are used to quantify the full-depth exchanges of water between the western boundary currents and the ocean interior. In the upper and intermediate layers, the westward transport associated with the southern branch of the South Equatorial Current was 49 Sv at the time of the cruise. The transports of the central and northern branches in the upper 200 m were 17 Sv and 12 Sv, respectively. After subtraction of the parts that recirculate in the subtropical, subequatorial, and equatorial domains, the fraction of the South Equatorial Current that effectively contributes to the warm water export to the North Atlantic is estimated at 18 Sv. The poleward boundary of the current southern branch is at 31S through the whole thickness of the subtropical gyre, but the latitude of the northern boundary varies from 7 degrees 30'S at the surface to 27S at 1400 m depth. The estimated latitude of its bifurcation into the Brazil Current and North Brazil Undercurrent also varies downward from about 14S at the surface to 28S at a depth of 600 m.In the North Atlantic Deep Water, eastward flows exceeding 10 Sv are observed at 3 degrees -4 degrees of latitude in both hemispheres, at 10S, and at 34S-30S. Between 4S and 17S, a net westward flow with an estimated transport of 19 Sv reinforces the southward deep western boundary current. Cyclonic circulations of Antarctic Bottom Water along the western boundaries of the Argentine and Brazil basins have amplitudes of 15 Sv and 13 Sv, respectively, exceeding those of the interbasin exchanges. The net alongshore transport of this water mass between the hydrographic section and the continental slope reverses to a southward direction from 13S to 27S, probably in relation with an eastward shift of the equatorward near-bottom boundary current at these latitudes.
Journal of Marine Research (0022-2402) (Yale University), 2000-11 , Vol. 58 , N. 6 , P. 1007-1039

Droits : 2000 Yale University
http://archimer.ifremer.fr/doc/2000/publication-803.pdf
DOI:10.1357/002224000763485782
http://archimer.ifremer.fr/doc/00000/803/

Éditeur(s) : Inter-research
Résumé : Marine protected areas (MPAs) have the potential to enhance the long-term sustainability of coastal resources, and the artisanal fisheries which depend on them. However, recreational fisheries, which are increasing their impacts on coastal resources worldwide, may reduce the benefits that MPAs provide to declining artisanal fisheries. Here we used the Bonifacio Straits Natural Reserve (BSNR) Corsica as a study case to simulate the combined effects on coastal resources of artisanal and recreational fishing efforts. The BSNR ecosystem was modelled using mass-balance modelling of trophic interactions. This model was compared to another built on a non-protected area from the same region. We aggregated fishing fleets into artisanal and recreational categories, and we simulated various combinations of fishing effort over a 20 yr dynamic simulation using Ecosim. We showed that fishing activities have an additional top-down effect on the food web and that they decrease the targeted group's biomass, such as piscivorous species. We found, for some trophic groups, non-trivial patterns of biomass variation through trophic cascades. Our trophic approach revealed that some groups may suffer a biomass decrease when MPAs are set or enforced, due to the combined effect of artisanal and recreational fisheries. Overall, our results illustrate the value of modelling to manage MPAs, as a complementary tool to surveys. Models provide the opportunity to anticipate the potential consequences, at the ecosystem level, of socio-political decisions that aim to sustain coastal resources while managing artisanal and recreational fisheries.
Marine Ecology-progress Series (0171-8630) (Inter-research), 2010-08 , Vol. 412 , P. 207-221

Droits : Inter-Research 2010
http://archimer.ifremer.fr/doc/00013/12436/9246.pdf
http://archimer.ifremer.fr/doc/00013/12436/9247.pdf
DOI:10.3354/meps08679
http://archimer.ifremer.fr/doc/00013/12436/

Résumé : This report synthesises the knowledge on the biogeochemical cycle, bioconcentration processes and ecotoxicity of lead in the marine environment. Man induced changes on the lead cycle, especially along the French coasts are reviewed. Concentration levels, mechanisms and fluxes between geochemical reservoirs are assessed. Emphasis is given on sublethal effects and toxicity mechanisms. Quality standards used in European Community countries are listed. Conclusions and recommendations for environmental management and research are given.
Le présent document constitue une synthèse des connaissances sur le cycle biogéochimique, la bioconcentration et l'écotoxicité du plomb en milieu marin. Il fait état des perturbations du cycle du plomb par l'action de l'homme, en particulier dans le milieu littoral français. Les niveaux de concentration et les quantités échangées entre les réservoirs géochimiques sont évalués. L'accent est mis sur les effets sublétaux et les mécanismes de toxicité vis-à-vis du biotope marin. Les réglementations relatives en milieu marin actuellement en vigueur dans les pays de la Communauté européenne sont répertoriées. Avec les conclusions quelques recommandations en matière de gestion et de recherche sont faites.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/1993/rapport-1449.pdf
http://archimer.ifremer.fr/doc/00000/1449/

Éditeur(s) : Wiley InterScience
Résumé : This paper reports on the status and design of the operational remotely operated vehicle Victor 6000, rated for 6000 m depth and of the 3000 m depth autonomous underwater vehicle Asterxx operated by Ifremer the French Institute for Sea Exploitation. Victor 6000 is part of a global system built of subsystems, scientific modules, winch and cable, dead weight and umbilical, positioning subsystem using acoustic ultra short base line (USBL) techniques, and software for data and dive management. In 2005 the system was equipped with a second toolsled dedicated to high resolution mapping of the sea bed, with both acoustical and optical devices. Asterxx, the first autonomous underwater vehicle (AUV) developed by IFREMER, is 4.5 m in length with a diameter of 0.69 m. Depending on the payload, its weight is between 600 and 800 kg in air,with a diving depth of 3000 m. Its cruising speed is between 0.5 and 2.5 ms. The AUV is capable of carrying various payloads for a wide spectrum of applications. The vehicle can cruise up to 100 km. For coastal applications this vehicle is operable by a limited crew potentially from a nonspecialized vessel. Both vehicles are used for oceanography as well as to continually evolve underwater systems to address new scientific challenges.
Journal of Field Robotics (1556-4959) (Wiley InterScience), 2007-06 , Vol. 24 , N. 6 , P. 449-459

Droits : 2007 Wiley InterScience
http://archimer.ifremer.fr/doc/2007/publication-2806.pdf
DOI:10.1002/rob.20195
http://archimer.ifremer.fr/doc/00000/2806/

Éditeur(s) : Université des Antilles Études caribéennes
Résumé : Dans les Antilles françaises, l’utilisation des espaces et des territoires pose des questions et suscite des problèmes aussi nombreux que complexes. Les unes et les autres, dépendant des caractéristiques propres à l’environnement et au contexte des milieux insulaires, sont tributaires des paramètres propres au contexte local, et notamment de facteurs identitaires. Les données historiques et les pesanteurs socio-culturelles y sont en effet souvent déterminantes. Il en résulte des situations qui d’attitudes et de comportements qui aujourd’hui encore se situent dans le domaine d’un non-droit, qu’il soit délibéré ou subi, ou à l’inverse génèrent de telles attitudes ou comportements.Les besoins de toute nature (occupation, utilisation, exploitation, valorisation, etc.) envers les espaces fonciers, au profit d’intérêts privés très divers et fréquemment conflictuels, s’y heurtent en outre à de nombreux obstacles, en particulier lorsqu’ils font l’objet d’une mobilisation à des fins touristiques. Ils tiennent autant à la superficie limitée des territoires, qu’à la rareté croissante des terres disponibles. Les impacts négatifs en sont aggravés par les exigences de conservation environnementale, qui se heurtent aux exigences des politiques d’urbanisme et de tourisme, qui tendent à se superposer et s’opposer en matière d’urbanisation touristique du littoral, espace aussi convoité que fragile.
In the French West Indies, the use of spaces and territories raises numerous and complex questions and problems. Both depend on the particular characteristics of the environment and the context of islands, and on parameters specific to the local context, including identity factors. The historical and socio-cultural constraints are indeed often critical. This results in situations that proceed, or conversely generate, attitudes and behaviours that still lie in the field of non-law, whether will full or suffered.The needs of any kind (occupation, use, exploitation, valuation, etc.) for land areas for the benefit of different and often conflicting private interests, stumble also many obstacles, especially when they are mobilized for tourism. They are due as much to the limited size of the territories, as to the increasing scar-city of available land. The negative impacts are exacerbated by the demands of environmental conservation that face the requirements of planning policies and tourism, which tend to overlap and oppose in tourist urbanization of coastal areas, which are spaces as coveted as fragile .
Martinique
Guadeloupe
Guyane française
Saint-Barthélemy
Saint-Martin

Droits : info:eu-repo/semantics/openAccess
urn:doi:10.4000/etudescaribeennes.6770
http://journals.openedition.org/etudescaribeennes/6770

Résumé : The maritime fisheries and mariculture guidance law passed in 1997 specifies that with the perspective of renegotiation of the common fisheries policy in 2002, a report on the special conditions of inshore fisheries be drawn up by the Government. To do so, the Minister of Agriculture and Fisheries entrusted this task to three experts, who are the authors of this report. In accordance with their remit, the situation of fisheries in territorial waters and estuaries of metropolitan France and the four DOM overseas departments ( counties) was examined, in the framework of meetings with professional fishermen, administrations, elected officials and scientific organisations. The first part situates fishing activities in coastal areas within the overall context of French fisheries. The second part provides a detailed report for each seafront (Channel, Atlantic, Mediterranean, West Indies, French Guyana and Reunion Island) on the regulatory framework, fleets, stocks, uses of resources and vulnerable areas of interest for fisheries. The report then analyses the competition within fisheries and with other activities (recreational fishing, extraction of aggregates, tourism, etc.). After these observations, the authors make ten proposals to improve the conditions under which coastal or inshore fisheries are practiced.
La loi d'orientation sur la pêche maritime et les cultures marines votée en 1997 précise que dans la perspective de la renégociation de la politique commune des pêches en 2002, un rapport sur les conditions particulières de l'exercice de la pêche dans la bande côtière sera établi par le Gouvernement. Pour y satisfaire, le Ministre de l'Agriculture et de la Pêche en a confié l'élaboration à trois experts, les auteurs du présent rapport. Conformément à la lettre de mission, la situation de la pêche dans les eaux territoriales et estuaires du territoire métropolitain et des quatre départements d'Outre-Mer a été examinée dans le cadre de rencontres avec les professionnels, les administrations, les élus, les organismes scientifiques. Une première partie permet de situer les activités halieutiques en zone côtière dans le contexte global de la pêche française. La seconde partie est un bilan détaillé par façade (Manche, Atlantique, Méditerranée, Antilles, Guyane, Réunion) du cadre réglementaire, des flottilles, des ressources, des usages de la ressource et des zones sensibles d'intérêt halieutiques. Le rapport analyse ensuite les compétitions au sein de la pêche et avec d'autres activités (pêche récréative, extractions de granulats, tourisme,...). A l'issue de ces différents constats, les auteurs font dix propositions pour améliorer les conditions d'exercice de la pêche en zone côtière.

Droits : info:eu-repo/semantics/openAccess
http://archimer.ifremer.fr/doc/2000/rapport-1200.pdf
http://archimer.ifremer.fr/doc/00000/1200/

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
Recent sedimentary facies and processes along the offshore slope of east Taiwan are investigated using a large set of geophysical and sedimentological data. The Taiwan orogen is often considered as one of the most tectonically active regions in the world and also suffers important climatic activity with an average of four typhoons per year. We have mapped in details the morphosedimentary features and characterized the sedimentary facies along offshore eastern Taiwan. There, we show that the slope is driven by a variety of erosional processes from mass wasting to turbidity current. Mass movements such as slides or mass transport deposits (MTDs) are ubiquitous and affect the whole east coast off Taiwan. Detailed core investigations, such as grain size analysis, chemical and mineralogical composition, revealed that turbidite facies range from thin fine-grained turbidites to thick massive turbidite facies. The detailed analysis of turbidite beds allow us to discuss the controlling factors of turbidity current generation. Turbidity currents represent an important sedimentary process that governs the slope morphology off east Taiwan. Triggering mechanisms likely range from slope instabilities related to earthquakes shaking to failure relative to climatic-controlled pulses of sediment supply. We propose that at least two end-members are characteristics in our turbidite records in term of controlling factor:1) Turbidity currents likely generated by tectonic activity and earthquakes shaking in particular; and2) Turbidity currents likely generated by climatic activity such as typhoon-induced floods.
ISSN: 0025-3227

hal-01277768
https://hal.archives-ouvertes.fr/hal-01277768
DOI : 10.1016/j.margeo.2015.05.013

Éditeur(s) : Elsevier Science Bv
Résumé : Small-scale fisheries have traditionally received less research effort than large-scale fisheries and are generally under-studied in Europe. In spite of their comparatively low volume of catches and economic importance, small-scale fisheries are socially important and an integral part of the European coastal zone. Considering the high heterogeneity of situations and the paucity of quantitative data, we used an analytical methodology based on the comparative method. We carried out an analysis of small-scale fisheries (SSFs) in Europe based on a selection of nine case studies. Our objective was to obtain a comprehensive description of small-scale fleets covering different areas/fisheries/species, encompassing the diversity and specific conditions under which SSFs operate, in order to demonstrate the ecological and social sustainability of this often overlooked fisheries segment. A common approach formulated so that the case studies could be compared with the case histories of other competing users, required that for each set of criteria – technical, biological, socio-economic, and institutional – a set of relevant items and indicators was established. An analysis of characteristics common to the selected case studies is conducted and an attempt made to extend our comparisons to the whole of the European Union. Our results show that (as compared with large-scale fleets, their main competitor) small-scale fleets: (i) are composed of smaller vessels and, consequently, travel lower distances to fishing grounds, and are more reliant on coastal areas; (ii) have smaller crews (although the global employment figure is similar to that of large-scale fleets in Europe); (iii) use mostly, but not exclusively, passive gears; (iv) use multi-purpose fishing approaches, and can change the fish species they target during the year; (v) have lower extraction rates; (vi) have lower total capital investments (including fishing rights), turnover and costs; and (vii) have lower fuel consumption, making them less sensitive to changing oil prices. Dependence on subsidies is lower (viii). Involvement in fisheries management is variable, conservation and access regulation measures are largely local in origin. For the selected case studies, the most significant competitors are large-scale fleets, and recreational fisheries, but other sources of interaction (water quality, invasive species, etc.) cannot be ignored.
Fisheries Research (0165-7836) (Elsevier Science Bv), 2013-02 , Vol. 140 , P. 1-13

Droits : 2012 Elsevier B.V. All rights reserved
http://archimer.ifremer.fr/doc/00118/22934/20757.pdf
DOI:10.1016/j.fishres.2012.11.008
http://archimer.ifremer.fr/doc/00118/22934/

Éditeur(s) : HAL CCSD Wiley
Résumé : [b]Aim[/b][br/] Many tropical tree species have poorly delimited taxonomic boundaries and contain undescribed or cryptic species. We examined the genetic structure of a species complex in the tree genus Carapa in the Neotropics in order to evaluate age, geographic patterns of diversity and evolutionary relationships, and to quantify levels of introgression among currently recognized species.[br/] [br/] [b]Location[/b][br/] Lowland moist forests in the Guiana Shield, the Central and Western Amazon Basin, Chocó and Central America.[br/] [br/] [b]Methods[/b][br/] Genetic structure was analysed using seven nuclear simple sequence repeats (nuSSR), five chloroplast SSRs (cpSSR), and two chloroplast DNA (cpDNA) intergenic sequences (trnH-psbA and trnC-ycf6). Bayesian clustering analysis of the SSR data was used to infer population genetic structure and to assign 324 samples to their most likely genetic cluster. Bayesian coalescence analyses were performed on the two cpDNA markers to estimate evolutionary relationships and divergence times.[br/] [br/] [b]Results[/b][br/] Two genetic clusters (nu_guianensis and nu_surinamensis) were detected, which correspond to the Neotropical species C. guianensis (sensu latu) and C. surinamensis. Fourteen cpDNA haplotypes clustered into six haplogroups distributed between the two nuclear genetic clusters. Divergence between the haplogroups was initiated in the Miocene, with some haplotype structure evolving as recently as the Pleistocene. The absence of complete lineage sorting between the nuclear and chloroplast genomes and the presence of hybrid individuals suggest that interspecific reproductive barriers are incomplete. NuSSR diversity was highest in C. guianensis and, within C. guianensis, cpDNA diversity was highest in the Central and Western Amazon Basin. Regional genetic differentiation was strong but did not conform to an isolation-by-distance process or exhibit a phylogeographical signal.[br/] [br/] [b]Main conclusions[/b][br/] The biogeographical history of Neotropical Carapa appears to have been influenced by events that took place during the Neogene. Our results point to an Amazonian centre of origin and diversification of Neotropical Carapa, with subsequent migration to the Pacific coast of South America and Central America. Gene flow apparently occurs among species, and introgression events are supported by inconsistencies between chloroplast and nuclear lineage sorting. The absence of phylogeographical structure may be a result of the ineffectiveness of geographical barriers among populations and of reproductive isolation mechanisms among incipient and cryptic species in this species complex.
ISSN: 0305-0270

hal-01032395
https://hal.archives-ouvertes.fr/hal-01032395
DOI : 10.1111/j.1365-2699.2011.02678.x

Éditeur(s) : HAL CCSD Elsevier
Résumé : The Gulf of Aigues-Mortes (NW Mediterranean Sea) is a midshelf zone whose scale is an intermediate between the nearshore scale (0–10 m depth) and the coastal scale (including the whole continental shelf). Its hydrodynamics is investigated for the first time. ADCP, CTD and thermosalinograph data were collected during three short cruises (HYGAM; March 6–7, 20–21, April 5–6, 2005). They were scheduled approximately every 15 days to sample the gulf circulation under different weather conditions. Moreover, the cruise data were used to validate the Symphonie model, a 3D primitive equations circulation model. The circulation features displayed by in situ data were well reproduced by Symphonie. A downscaling modelling approach was implemented, the largest scale being obtained by the replay of the MFSTEP regional model of the North-Western Mediterranean Sea. The analysis, closely coupling in situ measurements and model results, provides information that would not have been obtained using data separately. The great variability of the oceanic circulation at this scale is well evidenced. Winds are the main forces, not only locally but also at a larger scale. North winds generate coherent structures interacting with the general Mediterranean circulation. The explanation of the induced currents is then not straightforward, some of them being, for example, northward. South and southeast winds reinforce the sloping surface, the latter allowing the geostrophic equilibrium with longshore currents. This study, focused on the end of winter 2004–2005, also enhances the heat fluxes from offshore to nearshore, as well as the initiation of shelf dense waters. The knowledge of the midshelf oceanic circulation is then applied to run a numerical experiment which describes both the dispersion of a fictive contaminant from a point S (at the centre of the GAM), and evaluates the risk of contamination of the beaches along the GAM shores.
ISSN: 0278-4343

hal-00196620
https://hal.archives-ouvertes.fr/hal-00196620
DOI : 10.1016/j.csr.2007.06.006