62440 résultat(s)
Avenas Arthur

Malgré les avancées dans la prédiction de la trajectoire des cyclones tropicaux et des vitesses de vent en périphérie du système, la représentation numérique des vents les plus forts associés aux événements les plus intenses demeure une question ouverte, principalement en raison de la faible taille du coeur du cyclone et de la difficulté à comprendre et résoudre les échanges turbulents entre l’océan et l’atmosphère. Des limites observationnelles [...]

Despite substantial research and conservation efforts, many salmon populations are in decline. Globally, salmon research is not delivering effective decision support products to help managers apply research insights as informed management actions. Data Mobilization (DM) is a key step towards building the wider evidence base required to deliver accountable, reliable, and usable scientific advice to managers. Best practices for DM are being adopted [...]

Andre Guirec, Josset Quentin, Launey Sophie, Nevoux Marie, Beaulaton Laurent

La truite de mer, écotype migrant en mer de l'espèce truite commune (Salmo trutta), fait partie des douze espèces de poissons migrateurs amphihalins recensés en France. Ce rapport a pour objectif de présenter le contexte réglementaire, d'établir un état des populations et d'aborder les principales pressions impactant les populations sauvages de truite de mer de l'Hexagone. Cette synthèse montre des situations hétérogènes entre les différents bass [...]

Ariffin Effi Helmy, Sedrati Mouncef, Ismailuddin Aminah, Zainuddin Siti nur Hanani, Ramli Muhammad Zahirexpand

Coastal erosion is a worldwide issue in which the absence of sand dunes could alter the landscape of beaches, especially those in micro-tidal environments. Practically, hard structures, such as revetments, is effective in mitigating erosion but do not protect well and can change the beach’s natural landscape and appeal. Therefore, an eco-friendly approach using wooden fence in a beach dune at a coast in Terengganu, Malaysia, can act as an alterna [...]

Abdeina El Houssein, Jourdan Fred, Chazot Gilles, Bertrand Hervé, Le Gall Bernard

The annular Richat Structure, in Mauritania, is among the most striking geological features on Earth visible from space. Nicknamed “the Eye of Africa”, its intriguing concentric shaping has drawn attention for several decades. Formerly hypothesized as an astrobleme, it is now consensually recognized as a complex igneous intrusion, involving two ring-like gabbroic bodies, a central breccia and carbonatite dykes. However, the coexistence of until n [...]

Heubeck C., Beukes N., de Kock M., Homann M., Javaux E.j.expand

The BASE (Barberton Archean Surface Environments) scientific drilling project focused on re-covering unweathered continuous core through strata of the Paleoarchean Moodies Group (ca. 3.2 Ga), central Barberton Greenstone Belt (BGB), South Africa. They comprise some of the oldest well-preserved sedimentary strata on Earth, deposited within only a few million years in alluvial, fluvial, coastal-deltaic, tidal, and prodeltaic settings and represent [...]

Jaud Marion

Les Observations sont primordiales pour la compréhension du fonctionnement des processus naturels et de leur modélisation. La « durabilité » d’un observatoire repose en grande partie sur la stratégie d’observation mise en œuvre. Cette stratégie se doit d’allier faisabilité, fiabilité, pérennité et reproductibilité. Mais elle doit également être parcimonieuse en s’interrogeant sur la « juste mesure » de l’observation. Par ailleurs, le littoral est [...]

Villeneuve M., Bellon H., Guillou O., Gärtner A., Mueller P.a.expand

Several synthetic papers have been published about the geological structure of the threeWest African fold belts (Rokelides, Bassarides and Mauritanides), which were attached to the western margin of the West African Craton. Owing to the paucity of radiometric ages, some orogens and tectonic events have previously been confused and little consensus exists regarding their geodynamic evolution. Matching previous geological geochronological and geoph [...]

Sedrati M, Dalour L, Bulot G., Metge N.

Le présent document a pour objectif d’éclaircir le concept des solutions fondées sur la nature pour les risques littoraux en mettant l’accent sur la mosaïque d’actions possibles, leurs intérêts et les perspectives pour améliorer leur application. Ce document est réalisé dans le cadre du projet AdaLitt-Breizh.

Gouillieux Benoît, de Casamajor Marie-Noelle, Antajan Elvire, Dindinaud François, Francis Megan-Roseexpand

Nouveaux signalements de la méduse Rhizostoma luteum (Scyphoza: Rhizostomeae) dans le golfe de Gasgogne et mise à jour de sa distribution. Les auteurs rapportent de nouvelles observations de la méduse géante Rhizostoma luteum effectuées à partir d'observations de terrain et de base de données photographiques issues des sciences participatives entre 2017 et 2023. Ces observations indiquent la présence de cette espèce dans le sud du Golfe de Gascog [...]

In landscape ecology, the waterscape refers to permanent or temporary, running or stagnant surface waters within a terrestrial area. Across ecosystem boundaries, aquatic organisms and nutrients can reach terrestrial ecosystems, as formalised by the meta-ecosystem theory. Recent studies on aquatic insects emerging from temperate streams suggest that the extent of their biomass and fluxes across agricultural landscapes may have been neglected until [...]

Schaub Jessica, Leoni Valentina, Crochemore Sandrine, Blayac Hadrien, Kleinerman Benjaminexpand

Polyps are important stage in the medusozoan jellyfish life cycle, but the ecology of wild populations is still poorly understood. For some species, like Rhizostoma pulmo, polyps have never been reported in the wild. The Bages-Sigean lagoon is a Mediterranean, semi-enclosed lagoon with seasonally abundant Aurelia coerulea and R. pulmo medusae. Given its semi-closed nature and because ephyrae are commonly observed, it is likely that the polyps of [...]

Teyssier Mathilde, Desrosiers Catherine, Hellio Claire, Kerninon Fanny

Since 2011, coastal areas of the Caribbean Sea and the Tropical Atlantic Ocean have been exposed to massive influxes of pelagic sargassum algae. Coastal sargassum accumulations and brown water associated with their decomposition represent a new pressure threatening ecosystems, human health and the socio-economic sector. There is still a lack of well-calibrated monitoring methods to accurately characterise sargassum pressure at the scale of a terr [...]

Ben Gharbia Hela, Carr Brigid, Rolland Jean-Luc, Bersuder Philippe, Metian Marcexpand

Organophosphate esters (OPEs) are emerging organic contaminants due to their widespread use, environmental persistence and bioaccumulation potential. They are released into the environment and may affect the physiology of various marine organisms. To evaluate the effects of OPEs on marine microalgae, the phytoplankton species Isochrysis galbana was exposed to a mixture of 11 OPEs, and their impacts on growth, reactive oxygen species (ROS) product [...]

Poitrimol Camille, Thiébaut Éric, Boulart Cedric, Cathalot Cecile, Rouxel Olivierexpand

Ecosystems face various pressures, often leading to loss of biodiversity. Understanding how biodiversity is spatially structured, what are the driving factors, and the ecological and evolutionary processes involved is essential to assess communities' resilience to disturbances and guide efficient conservation measures. Hydrothermal vents from national waters of the West Pacific are targeted by mining industries for their mineral resources that in [...]