60140 résultat(s)
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 [...]

The hydrography of the central Greenland Sea was reconstructed from observations including bottle measurements, Conductivity/Temperature/Depth (CTD) measurements, and Argo floats for the period 1950 to 2020. Greenland Sea Deep Water was renewed during bottom-reaching convection prior to the mid-1980s, facilitated by the thermobaric effect. During a period of shallow convection in the late 1980s and early 1990s, a stratification maximum formed and [...]

Litchman Elena, Villéger Sébastien, Zinger Lucie, Auguet Jean-Christophe, Thuiller Wilfriedexpand

The influential concept of the rare biosphere in microbial ecology has underscored the importance of taxa occurring at low abundances yet potentially playing key roles in communities and ecosystems. Here, we refocus the concept of rare biosphere through a functional trait-based lens and provide a framework to characterize microbial functional rarity, a combination of numerical scarcity across space or time and trait distinctiveness. We demonstrat [...]

Lee Guan-Hong, Jung Nathalie, Dellapenna Tim, Ra Kongtae, Chang Jongwiexpand

Estuaries, vital coastal ecosystems, face growing threats from industrialization. To understand the pace of sedimentary changes and heavy metal pollution at the anthropogenically altered and industrialized Nakdong River Estuary in South Korea, we used sediment coring to reconstruct environmental change. Estuarine dam construction in 1934 shifted the sedimentary system from sand to mud, coinciding with a post-1930s mercury increase due to coal bur [...]

Fabri-Ruiz Salome, Berdalet E., Ulses C., Somot S., Vila M.expand

Fast environmental changes and high coastal human pressures and impacts threaten the Mediterranean Sea. Over the last decade, recurrent blooms of the harmful dinoflagellate Ostreopsis cf. ovata have been recorded in many Mediterranean beaches. These microalgae produce toxins that affect marine organisms and human health. Understanding the environmental conditions that influence the appearance and magnitude of O. cf. ovata blooms, as well as how c [...]

Tenacibaculum discolor develops biofilm in marine aquaculture production tanks and is identified as one of the causative agents of tenacibaculosis, a bacterial disease that causes significant losses in marine aquaculture production. In this study, the biofilm characteristics of T. discolor strain FMCC B487 were evaluated. Cell growth and biofilm formation and development were studied in miniaturized assays to assess the effect of different levels [...]

Dans le contexte du changement climatique, l’objectif général du réseau ECOSCOPA est de pérenniser les dispositifs d’observation basés sur différents écosystèmes côtiers, et d’y ajouter de nouveaux indicateurs physiologiques et environnementaux, contribuant à une analyse pertinente de l’intégralité́du cycle de vie de l’huître creuse en lien avec les pressions climatiques subies. L’observatoire ECOSCOPA permet aux professionnels des cultures marin [...]

Huang Enqing, Yuan Zijie, Wang Shihe, Yang Ying, Jia Guodongexpand

The distribution of vegetation across glacial Sundaland and the underlying mechanisms have long been debated. We address this issue by comparing a compilation of vegetation reconstructions with climate simulations from the Community Earth System Model 2 (CESM2). A new n-alkane δ13C record derived from higher plants, covering the period from 21 to 5 cal ka BP in the southern South China Sea, is presented. This record, combined with previous pollen [...]

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, and have also been used as the basis of new statistical component separation algorithms. In the context of upcoming cosmological surveys, [...]