60153 résultat(s)
Gazeau Frédéric, Urrutti Pierre, Dousset Alexandre, Brodu Nicolas, Richard Marionexpand

Human activities over the past 150 yr have led to significant carbon dioxide (CO2) emissions, causing global warming and ocean acidification. Surface ocean temperature has risen by 0.93°C since 1850, with projections of an additional +1.42°C to 3.47°C by 2080–2099. Ocean acidification, driven by CO2 absorption, has already lowered seawater pH by 0.1 units, affecting calcifying organisms, including shelled mollusks. Long-term multigenerational stu [...]

Rangel-Buitrago Nelson, Ben-Haddad Mohamed, Galgani Francois, Pereira da Silva Carlos, Neal William j.

This opinion paper emphasizes the often overlooked but significant issue of animal waste (AW) pollution on beaches, encompassing waste from domestic pets, livestock, wildlife, avians, aquatic animals, zoo animals, and insects. Animal waste pollution affects beach environments, leading to nutrient loading, chemical contamination, and pathogen transmission. Furthermore, this type of pollution degrades water quality, impacting tourism and local econ [...]

WGALES échange des idées, des méthodologies et des développements et travaille sur la standardisation des enquêtes sur les larves et les oeufs de poisson (ichtyoplancton) dans la zone CIEM, ainsi que pour fournir une plate-forme à partir de laquelle améliorer les évaluations basées sur les enquêtes. Plusieurs études d'ichtyoplancton sont réalisées dans les zones CIEM, toutes coordonnées par leur propre groupe d'experts. Dans le passé, ces groupes [...]

Les réunions en présentiel au sein de ce groupe ont repris cette année après plusieurs années d’organisation de réunions en distanciel du fait de la crise du covid. Par ailleurs, il s’agissait d’une réunion importante, car ce groupe finalise un cycle pluriannuel de trois ans après lequel il doit renouveler sa programmation de travail pour les années à venir, notamment le rafraîchissement de ses ToRs et de la stratégie de valorisation et d’impact [...]

Leroux Riwan, Pepino Marc, Magnan Pierre, Bertolo Andrea

While it is well-accepted that predation plays a key role in shaping both size structure and species composition in natural ecosystems, fine-scale variation in predation risk within ecosystems has been largely neglected. The objective of this study was to use normalised size spectra (NSS) to investigate whether small-scale spatial variation in predation risk (by fish) can modulate zooplankton community structure at the within-lake level in a smal [...]

Morfin Marie, Sourget Quiterie, Mehault Sonia

La réduction des rejets de pêche est une préoccupation majeure des gestionnaires de la ressource halieutique. La modification des engins par une augmentation des maillages ou l’insertion de dispositifs sélectifs est un des moyens mis en œuvre par les pêcheurs pour réduire les captures d’individus hors taille marchande ou les espèces indésirées. Des expérimentations sont régulièrement mises en œuvre à bord de navires professionnels pour quantifier [...]

Mousset Louise, Allys Erwan, Price Matthew a., Aumont Jonathan, Delouis Jean Marcexpand

Scattering transforms are a new type of summary statistics recently developed for the study of highly non-Gaussian processes, which have been shown to be very promising for astrophysical studies. In particular, they allow one to build generative models of complex non-linear fields from a limited amount of data. In the context of upcoming cosmological surveys, the extension of these tools to spherical data is necessary. We develop scattering trans [...]

Ce rapport présente une synthèse des actions et travaux réalisés par le laboratoire Santé Environnement et Microbiologie (LSEM) pendant l’année 2023. Les actions du Laboratoire National de Référence pour la Microbiologie des Coquillages, les activités de la coordination du réseau REMI sont présentées, et s’accompagnent de résumés des projets de recherche et des derniers développements de méthodes.

Chowdhury Subhadeep, Berthelot Hugo, Baudet Corentin, González-Santana David, Reeder Christian Furboexpand

Dinitrogen (N2) fixation represents a key source of reactive nitrogen in marine ecosystems. While the process has been rather well-explored in low latitudes of the Atlantic and Pacific Oceans, other higher latitude regions and particularly the Indian Ocean have been chronically overlooked. Here, we characterize N2 fixation and diazotroph community composition across nutrient and trace metals gradients spanning the multifrontal system separating t [...]

Ventura Mariana, Oroy Cloé, Llopis Monferrer Natalia, Le Grand Fabienne, Long Marcexpand

Thraustochytrids biomass, rich in docosahexaenoic acid (DHA), could be a sustainable ingredient for the aquafeed industry. However, its production cost renders it less competitive than fishmeal and fish oil from wild-caught fish. This study proposes optimizing the hydrolysis conditions of thraustochytrid biomass to generate an ingredient with improved properties thanks to the production of peptides with different biological activities. The improv [...]

Frieler Katja, Volkholz Jan, Lange Stefan, Schewe Jacob, Mengel Matthiasexpand

This paper describes the rationale and the protocol of the first component of the third simulation round of the Inter-Sectoral Impact Model Intercomparison Project (ISIMIP3a, http://www.isimip.org, last access: 2 November 2023) and the associated set of climate-related and direct human forcing data (CRF and DHF, respectively). The observation-based climate-related forcings for the first time include high-resolution observational climate forcings [...]

Maire Yanis, Schmitt François g, Kormas Konstantinos, Vasileiadis Sotirios, Caruana Amandineexpand

Turbulence is one of the least investigated environmental factors impacting the ecophysiology of phytoplankton, both at the community and individual species level. Here, we investigated, for the first time, the effect of a turbulence gradient (${\rm{Reynolds\ number}}$, from ${\rm{R}}{{\rm{e}}}_{\rm{\lambda }} = 0$ to ${\rm{R}}{{\rm{e}}}_{\rm{\lambda }} = 360$) on two species of the marine diatom Pseudo-nitzschia and their associated bacterial co [...]

Evangelista Charlotte, Kamenova Stefaniya, Diaz Pauli Beatriz, Sandkjenn Joakim, Vøllestad Leif Asbjørnexpand

Unravelling evolution-by-environment interactions on the gut microbiome is particularly relevant considering the unprecedented level of human-driven disruption of the ecological and evolutionary trajectories of species. Here, we aimed to evaluate whether an evolutionary response to sizeselective mortality influences the gut microbiome of medaka (Oryzias latipes), how environmental conditions interact with the genetic background of medaka on their [...]

Fourrier Pierre, Dulaquais Gabriel

The low‐molecular‐weight (LMW) reduced sulfur substances (RSS) composition of dissolved organic matter (DOM) was examined along the GEOTRACES US‐GP15 section in the Pacific Ocean. We demonstrate that LMW RSS constitutes a significant fraction of nonvolatile dissolved organic sulfur (DOS). While thiols such as glutathione were below our detection limit (300 pM), RSS containing two carbon (C) sulfur (S) bonds were present at concentrations in the h [...]

Caley Thibaut, Souron Antoine, Uno Kevin t., Macho Gabriele a.

The relationship between climate and human evolution is complex, and the causal mechanisms remain unknown. Here, we review and synthesize what is currently known about climate forcings on African landscapes, focusing mainly on the last 4 million years. We use information derived from marine sediment archives and data-numerical climate model comparisons and integration. There exists a heterogeneity in pan-African hydroclimate changes, forced by a [...]

Le Quinio Azenor, Martignac F., Girard A., Guillard J., Roussel J-M.expand

Acoustic cameras are increasingly used for continuous, non-intrusive recording and counting of fish passage in natural environments and artificial structures such as fishways. However, analysing the large number of videos recorded is time consuming. Although automatic reading processes have been developed, the poor quality of acoustic images, including discontinuity of the signal for a single object, is challenging. We developed an innovative met [...]

Boukhari Sofiane, Kertous Mourad, Nassiri Abdelhak, Maliki Samir b.

The purpose of this article is to evaluate the water company in Algeria (ADE) subscribers’ Willingness To Pay (WTP) for a better service offer. This study assessed the WTP for improved drinking water in the department of Souk-Ahras (Algeria), using contingent valuation survey data of 5,342 households, with a response rate of 10.86% (greater than 10% of each municipality's total number of subscribers). Then, Probit and Tobit models were applied to [...]

Dawkins Matthew, Prior Jack, Lewis Bryon, Faillettaz Robin, Banez Thompsonexpand

Tracking and classifying fish in optical underwater imagery presents several challenges which are encountered less frequently in terrestrial domains. Video may contain large schools comprised of many individuals, dynamic natural backgrounds, highly variable target scales, volatile collection conditions, and non-fish moving confusers including debris, marine snow, and other organisms. Additionally, there is a lack of large public datasets for algo [...]

Pérez Agúndez José a., Raux Pascal, Lancelot Loeiza, Rougier Jean-Emmanuel

Aquaculture development is a challenge for the economic growth of coastal territories and to promote the food security of their populations. Many efforts have been made by international, national, and local public institutions to develop this sector. Despite this political objective, the coastal zones of Europe and the Mediterranean in general are faced with problems that strongly limit this development. This is linked to several factors, includi [...]