A5005878186- Marine Biology and Ecology Research
- Geochemistry and Elemental Analysis
- Marine and coastal ecosystems
- Isotope Analysis in Ecology
- Geology and Paleoclimatology Research
- Groundwater and Isotope Geochemistry
- Heavy metals in environment
- Mercury impact and mitigation studies
- Aquatic Ecosystems and Phytoplankton Dynamics
- Marine and environmental studies
- Microbial Community Ecology and Physiology
- Methane Hydrates and Related Phenomena
- Radioactive element chemistry and processing
- Recycling and Waste Management Techniques
- Water Quality and Pollution Assessment
- Geological formations and processes
- Geochemistry and Geologic Mapping
- Odor and Emission Control Technologies
- Microplastics and Plastic Pollution
- Corrosion Behavior and Inhibition
- Electrochemical Analysis and Applications
- Radioactive contamination and transfer
- Advanced Theoretical and Applied Studies in Material Sciences and Geometry
- Legume Nitrogen Fixing Symbiosis
- Aquatic Invertebrate Ecology and Behavior
Université de Pau et des Pays de l'Adour
2022-2024
Institut des Sciences Analytiques et de Physico-Chimie pour l'Environnement et les Matériaux
2020-2024
Centre National de la Recherche Scientifique
2014-2024
University of Delaware
2018-2023
IMT Atlantique
2019
Laboratoire de Physique Subatomique et des Technologies Associées
2019
Université d'Angers
2014-2018
Earth University
2018
Nantes Université
2015-2016
Laboratoire de Planétologie et Géosciences
2014-2016
This study presents a new approach combining diffusive equilibrium in thin-film (DET) and spectrophotometric methods to determine the spatial variability of dissolved iron reactive phosphorus (DRP) with single gel probe. Its originality is (1) postpone up three months colorimetric reaction DET by freezing (2) measure simultaneously DRP hyperspectral imaging at submillimeter resolution. After few minutes room temperature, thawed sandwiched between two monospecific reagent gels, leading...
Abstract. We present a new rapid and accurate protocol to simultaneously sample benthic living foraminifera in two dimensions centimetre-scale vertical grid dissolved iron phosphorus at high resolution (200 μm). Such an approach appears crucial for the study of foraminiferal ecology highly dynamic heterogeneous sedimentary systems, where shows strong variability centimetre scale. On studied intertidal mudflat Loire estuary, faunas are dominated by Ammonia tepida, which accounts 92 %...
Significance The Fe-catalyzed oxidation of sulfide by dioxygen in hydrothermal vent plumes is shown to be a source reactive oxygen species (ROS) the deep ocean. ROS are class powerful oxidants, most which can react with recalcitrant organic molecules at near diffusion limited rates. production systems may comparable known photochemical yields surface waters. discovery this abundant demonstrates mechanism for alteration refractory matter
The present study describes new procedures to obtain at millimeter resolution the spatial distribution of nitrite and nitrate in porewaters, combining diffusive equilibrium thin films (DET), colorimetry hyperspectral imagery. Nitrite can be easily achieved by adapting well-known colorimetric method from Griess (1879) using a common flatbed scanner with limit detection about 1.7 μmol L(-1). Nitrate obtained after reduction into vanadium chloride reagent. However, concentration used this...
Despite 20 years of control on eutrophication, episodes summer hypoxia still occur in the Loire estuary, impacting water quality and posing a key scientific management challenge. This work aimed to quantify contribution benthic compartment estuary by direct measurement water–sediment fluxes an in-depth understanding seasonal variations oxides phosphorus stocks. During summer’s low-discharge period, results show that iron oxide-rich deposit is stable under hypoxic conditions, limiting release...
This study presents a new gel based technique to describe the pore water ammonium distribution through sediment-water interface in two dimensions at millimeter scale. The is an adaptation of classical colorimetric method on Berthelot's reaction. After thin film probe was equilibrated by diffusion either standard solutions or waters, reagent set probe, allowing development characteristic green color. A flatbed scanner and subsequent densitometry image analysis allowed determine concentration...
Abstract. We present a new rapid and accurate protocol to simultaneously sample benthic living foraminifera in two dimensions centimeter scale vertical grid dissolved iron high resolution (200 μm). Such an approach appears crucial study foraminiferal ecology heterogeneous environments. The faunas of the main intertidal mudflat Loire estuary are dominated by Ammonia tepida, which accounts for 92 % assemblage (CTG-labeled). Its distribution shows first density maximum at surface, sharp...
Abstract The sulphur cycle has a key role on the fate of nutrients through its several interconnected reactions. Although cycling in aquatic ecosystems been thoroughly studied since early 70’s, characterisation saline endorheic lakes still deserves further exploration. Gallocanta Lake (NE Spain) is an ephemeral inland lake whose main sulphate source found bed minerals and leads to dissolved concentrations higher than those seawater. An integrative study including geochemical isotopic...
Siderophores are natural metal chelating agents that strongly control the biogeochemical cycles such as Fe in environment. This article describes a new methodology to detect and quantify at micromolar concentration spatial distribution millimeter scale of siderophores within root's system. The "universal" CAS assay originally designed for bacterial detection later fungus was adapted here diffusive equilibrium thin film gel techniques (DET). method calibrated against marketed desferrioxamine...
Abstract. The alkalinity dynamics in coastal environments play a crucial role controlling the global burial of carbonate minerals and ocean's capacity to sequester anthropogenic CO2. This study presents results from high vertical resolution profiles obtained during two summers temperate Chesapeake Bay estuary, enabling detailed investigation over salinity redox gradients, along with measurement speciation most redox-sensitive elements. Under oxygen-rich conditions, dissolution, primary...
Abstract We measured the speciation of dissolved Mn from surface to just above hydrothermal vents at 9°50′N East Pacific Rise in open ocean over a 3‐week period. Total concentrations ranged 2.2 135 nmol L −1 with significant contribution Mn(III) bound humic acid one third our samples representing up 64% total Mn. These complexes were mostly detected vent plume and redox boundaries oxygen minimum zone water column. In plume, Mn(III)‐humic stabilized manganese solution ~ 10,000‐fold dilution...