A5058658820- Marine and coastal ecosystems
- Microbial Community Ecology and Physiology
- Marine Biology and Ecology Research
- Methane Hydrates and Related Phenomena
- Ocean Acidification Effects and Responses
- Arctic and Antarctic ice dynamics
- Atmospheric and Environmental Gas Dynamics
- Microplastics and Plastic Pollution
- Atmospheric chemistry and aerosols
- Oceanographic and Atmospheric Processes
- Genomics and Phylogenetic Studies
- Isotope Analysis in Ecology
- Protist diversity and phylogeny
- Aquatic Ecosystems and Phytoplankton Dynamics
- Soil and Water Nutrient Dynamics
- Marine Biology and Environmental Chemistry
- Marine and coastal plant biology
- Environmental DNA in Biodiversity Studies
- Marine and environmental studies
- Odor and Emission Control Technologies
- Folate and B Vitamins Research
- Yersinia bacterium, plague, ectoparasites research
- Marine Toxins and Detection Methods
- Membrane Separation Technologies
- Marine and Offshore Engineering Studies
Laboratoire d'Océanographie Microbienne
2013-2024
Sorbonne Université
2014-2024
Centre National de la Recherche Scientifique
2013-2024
Institut de Ciències del Mar
2012-2022
Pierre Fabre (France)
2022
Institut Català de Ciències del Clima
2012-2019
Consejo Superior de Investigaciones Científicas
2013-2018
Observatoire Océanologique de Banyuls-sur-Mer
2009-2014
Université Paris Cité
2010-2013
Universidad de Granada
2006-2012
In midsummer, diatoms have taken advantage of thinning ice cover to feed in nutrient-rich waters.
Marine dissolved organic matter (DOM) is one of the largest reservoirs reduced carbon on Earth. In dark ocean (>200 m), most this refractory DOM. This DOM, largely produced during microbial mineralization matter, includes humic-like substances generated in situ and detectable by fluorescence spectroscopy. Here we show two ubiquitous fluorophores with turnover times 435±41 610±55 years, which persist significantly longer than ~350 years that global takes to renew. parallel, decay a...
Abstract. We explored the patterns of total and active bacterial community structure in a gradient covering surface waters from Mackenzie River to coastal Beaufort Sea Canadian Arctic Ocean, with particular focus on free-living (FL) vs. particle-attached (PA) communities. Capillary electrophoresis–single-strand conformation polymorphism (CE-SSCP) showed significant differences when comparing river, coast open sea structures. In contrast river waters, (16S rDNA-based) rRNA-based) communities...
Climate warming affects the development and distribution of sea ice, but at present evidence polar ecosystem feedbacks on climate through changes in atmosphere is sparse. By means synergistic atmospheric oceanic measurements Southern Ocean near Antarctica, we that microbiota ice ice-influenced ocean are a previously unknown significant source organic nitrogen, including low molecular weight alkyl-amines. Given keystone role nitrogen compounds aerosol formation, growth neutralization, our...
We assessed the effects of Saharan dust inputs particulate matter (PM), total phosphorus (TP), nitrogen, and water soluble organic carbon (WSOC) on bacterial abundance (BA) in two alpine lakes reservoirs Mediterranean region. also experimentally activity community composition explored presence airborne bacteria. found synchronous BA dynamics at least one study years for each corresponding pair ecosystems, suggesting an external control. The link between PM, WSOC, or TP occurred only those...
Chromophoric dissolved organic matter (CDOM), the optically active fraction of matter, is primarily generated by pelagic organisms in open ocean. In this study, we experimentally determined quantity and spectral quality CDOM bacterioplankton using two different substrates (with without photoproducts) Antarctic krill Euphausia superba evaluated their potential contributions to dynamics peninsular region Southern Ocean. was bacteria all experiments, presence photoproducts influenced both...
Abstract The omnipresence of chromophoric dissolved organic matter (CDOM) in the open ocean enables its use as a tracer for biochemical processes throughout global overturning circulation. We made an inventory CDOM optical properties, ideal water age ( τ ), and apparent oxygen utilization (AOU) along Atlantic, Indian, Pacific Ocean waters sampled during Malaspina 2010 expedition. A mass analysis was applied to obtain intrinsic, hereinafter archetypal, values , AOU, rate (OUR), absorption...
Major changes to Arctic marine ecosystems have resulted in longer growing seasons with increased phytoplankton production over larger areas. In the Chukchi Sea, high productivity fuels intense benthic denitrification creating a nitrogen (N) deficit that is transported through Atlantic Ocean, where it likely fixation. Given rapid pace of environmental change and potentially globally significant N deficit, we conducted experiments aimed at understanding microbial utilization Sea. Ship-board...
Abstract. Transparent exopolymer particles (TEP) are the most ubiquitous gel in ocean and form abiotically from dissolved precursors. Although these can accumulate at surface, being thus exposed to intense sunlight, role of solar radiation for assembly degradation TEP is unknown. In this study, we experimentally determined effects visible ultraviolet B (UVB) on (1) (photolysis experiments), (2) polymers (photoinhibition experiments) (3) release by microorganisms. Solar radiation,...
Abstract Biotic and abiotic particles shape the microspatial architecture that defines microbial aquatic habitat, being highly variable in size quality along oceanic horizontal vertical gradients. We analysed prokaryotic (bacterial archaeal) diversity community composition present six distinct particle classes ranging from pico‐ to microscale (0.2 200 μm). Further, we studied their variations oceanographic (from coast open waters) ocean surface into meso‐ bathypelagic ocean) In general, was...
Abstract. A better understanding of how environmental changes affect organic matter fluxes in Arctic marine ecosystems is sorely needed. Here we combine mooring times series, ship-based measurements and remote sensing to assess the variability forcing factors vertical particulate carbon (POC) across Mackenzie Shelf 2009. We developed a geospatial model these proceed an integrative analysis their determinants summer. Flux data were obtained with sediment traps moored around 125 m via regional...
Abstract. During August 2009, measurements of bacterial abundance and nucleic acid content were made along with production respiration in coastal waters the Beaufort Sea (Arctic Ocean), an area influenced by Mackenzie River inflow. The main purpose was to evaluate organic carbon processing respect local sources, mainly primary river inputs. Bacterial generally decreased from offshore surface deep waters. In contrast, percentage high bacteria higher rather than or Statistical analyses...
Abstract The Mediterranean Sea is a miniature ocean divided by the Sicily Strait into two basins with marked west to east trophic gradient and separated of nearby eastern Atlantic Ocean Gibraltar. Here, we test hypothesis that these physical environmental barriers favor development specific prokaryotic assemblages, leading changes in community structure both vertical horizontal spatial scales. By analyzing taxonomic phylogenetic diversity using amplicon sequence variants (ASVs) 16S rRNA...
Abstract. Transparent exopolymer particles (TEPs) are a class of gel particles, produced mainly by microorganisms, which play important roles in biogeochemical processes such as carbon cycling and export. TEPs (a) colonized carbon-consuming microbes; (b) mediate aggregation sinking organic matter organisms, thereby contributing to the biological pump; (c) accumulate surface microlayer (SML) affect air–sea gas exchange. The first step evaluate global influence these is prediction TEP...
Summary Marine heterotrophic prokaryotes (HP) play a key role in organic matter processing the ocean; however, view of HP as dissolved (DOM) sources remains underexplored. In this study, we quantified and optically characterized DOM produced by two single marine bacterial strains. We then tested availability these to situ Mediterranean Sea communities. Two strains were used: Photobacterium angustum (a copiotrophic gammaproteobacterium) Sphingopyxis alaskensis (an oligotrophic...
Abstract. The MALINA oceanographic campaign was conducted during summer 2009 to investigate the carbon stocks and processes controlling fluxes in Mackenzie River estuary Beaufort Sea. During campaign, an extensive suite of physical, chemical biological variables were measured across seven shelf–basin transects (south–north) capture meridional gradient between open ocean. Key such as temperature, absolute salinity, radiance, irradiance, nutrient concentrations, chlorophyll a concentration,...