A5027927514- Marine and coastal ecosystems
- Marine Biology and Ecology Research
- Microbial Community Ecology and Physiology
- Maritime Navigation and Safety
- Maritime Transport Emissions and Efficiency
- Oceanographic and Atmospheric Processes
- Offshore Engineering and Technologies
- Atmospheric chemistry and aerosols
- Isotope Analysis in Ecology
- Protist diversity and phylogeny
- Oil Spill Detection and Mitigation
- Marine Bivalve and Aquaculture Studies
- Atmospheric aerosols and clouds
- Marine Ecology and Invasive Species
- Water Quality Monitoring Technologies
- Water Quality Monitoring and Analysis
- Marine animal studies overview
- Mercury impact and mitigation studies
- Underwater Acoustics Research
- Aquatic Ecosystems and Phytoplankton Dynamics
- Underwater Vehicles and Communication Systems
- Ocean Acidification Effects and Responses
- Air Quality Monitoring and Forecasting
- Marine and fisheries research
- Oral microbiology and periodontitis research
Institut de Recherche pour le Développement
2014-2025
Centre National de la Recherche Scientifique
2014-2025
Institut Méditerranéen d’Océanologie
2015-2025
Université de Toulon
2015-2025
Aix-Marseille Université
2014-2024
Laboratoire d’Océanologie et de Géosciences
2011-2015
Université du Québec à Rimouski
2011
Institut de Microbiologie de la Méditerranée
2005-2010
Institut de Neurobiologie de la Méditerranée
2009-2010
Laboratoire de Biotechnologie et Chimie Marines
2006-2009
Abstract Diatoms are one of the major primary producers in ocean, responsible annually for ~20% photosynthetically fixed CO 2 on Earth. In oceanic models, they typically represented as large (>20 µm) microphytoplankton. However, many diatoms belong to nanophytoplankton (2–20 and a few species even overlap with picoplanktonic size-class (<2 µm). Due their minute size difficulty detection poorly characterized. Here we describe massive spring bloom smallest known diatom ( Minidiscus )...
The bactericidal effect of photocatalysis with TiO2 is well recognized, although its mode action still poorly characterized. It may involve oxidation, as illuminated generates reactive oxygen species. Here we analyze the in NaCl-KCl or sodium phosphate solutions. We found that adsorption bacteria on catalyst occurred immediately solution, whereas it was delayed solution. also show rate cells onto positively correlated effect. Importantly, consistently associated a reduction loss bacterial...
Most of phytoplankton influence is barely understood at the sub meso scale and daily because lack means to simultaneously assess functionality, dynamics community structure. For a few years now, it has been possible address this objective with an automated in situ high frequency sampling strategy. In order study environmental short-term events (nutrients, wind speed, precipitation, solar radiation, temperature salinity) on onset bloom oligotrophic Bay Villefranche-sur-Mer (NW Mediterranean...
Abstract One pathway by which the oceans influence climate is via emission of sea spray that may subsequently cloud properties. Sea emissions are known to be dependent on atmospheric and oceanic physicochemical parameters, but potential role ocean biology fluxes remains poorly characterized. Here we show a consistent significant relationship between seawater nanophytoplankton cell abundances sea-spray derived Cloud Condensation Nuclei (CCN) number fluxes, generated using water from three...
The recent development of biological sensors has extended marine plankton studies from conducting laboratory bench work to in vivo and real-time observations. Flow cytometry (FCM) shed new light on microorganisms since the 1980s through its single-cell approach robust detection smallest cells. FCM records valuable optical properties scattering fluorescence cells passing a single file front narrow-collimated source, recording tens thousands within few minutes. Depending instrument settings,...
Abstract. Marine aerosol observations from 6 shipborne campaigns carried out in 2021 and 2023 the southwest Indian Ocean are presented. A set of instruments is used to study spatial temporal variability size distribution, cloud condensation nuclei (CCN), activation diameters, hygroscopicity (κ). Total number aerosols (Na) shows concentration above 1500 cm-3 polluted areas, between 100–1500 open ocean. CCN measurements (0.2 %, 0.4 % supersaturation) range 40 500 cm-3. At 0.2 (0.4 %)...
Assessing and understanding the factors that control biological carbon pump (BCP), i.e. transfer of organic biologically fixed by primary production (PP) from euphotic zone to deep ocean, remains a major challenge in marine biogeochemistry. Among these factors, intensity PP structure phytoplankton community play key roles biogeochemical fluxes BCP depend on physico-chemical conditions ocean. Although has received significant attention last decades, magnitude this process poorly quantified,...
The intricate relationship between trophic levels in marine ecosystems remains largely unexplored, particularly the Southern Ocean. To investigate complex composition of water constituents, notably phytoplankton community, we used machine learning techniques to classify six bio-optical classes from a comprehensive ocean-color data time-series. In situ Ocean further characterized these by predominant types. Biologging southern elephant seals revealed that 60% prey-catch attempts were...
Addressing hydrological, biogeochemical and biological variability in marine systems at different scales is essential for understanding their functioning fate the context of global change increasing anthropogenic pressure. Sub-mesoscale features processes are particularly relevant coastal, marginal shelf seas, frontal (such as Regions Of Freshwater Influence, tidal fronts, upwelling eddies), being sensitive to extreme events influencing human health, economy, well-being. Phytoplankton...
Phytoplankton observation is the product of a number trade-offs related to sampling processes, required level diversity and size spectrum analysis capabilities techniques involved. Instruments combining morphological high-frequency for phytoplankton cells are now available. This paper presents an application automated high-resolution flow cytometer Cytosub as tool analysing phytoplanktonic in their natural environment. High resolution data from temporal study Bay Marseille (analysis every 30...
Phytoplankton is a key component in marine ecosystems. It responsible for most of the primary production, particularly eutrophic lagoons, where it frequently blooms. Because they are very sensitive to their environment, dynamics these microbial communities has be observed over different time scales, however, assessment short term variability often out reach traditional monitoring methods. To overcome limitations, we set up Cytosense automated flow cytometer (Cytobuoy b.v), designed high...
Abstract. Phytoplankton observation in the ocean can be a challenge oceanography. Accurate estimations of its biomass and dynamics will help to understand ecosystems refine global climate models. Relevant data sets phytoplankton defined at functional level on sub-meso- daily scale are thus required. In order achieve this, an automated, high-frequency, dedicated scanning flow cytometer (SFC, Cytobuoy b.v., Netherlands) has been developed cover entire size range cells whilst simultaneously...
In this study, the abundance and properties (size, shape, polymer type) of microplastics (MPs) in sea surface water samples, collected during two sampling campaigns over 2018–2019, four coastal areas Mediterranean Sea (Saronikos Gulf, LIgurian Sea, Gulf Lion, Gabes Gulf) were investigated. Coupled hydrodynamic/particle drift model simulations with basin-scale high resolution nested models used to provide a better understanding on variability abundance/size MPs, originating from wastewater...
Short-term variations of phytoplankton communities are poorly documented. To overcome these limitations and make observations on a short-time (hours) scale, we moored submersible flow cytometer (CytoBuoy b.v.) in the Bay Marseille. The CytoSub monitored every 30 min at fixed site (2 m depth) during summer 2005. data treatment, conducted basis pulse-shape analysis, resolved seven clusters. Daily sampling nutrients continuous information salinity, temperature wind speed allowed distinction...
Abstract Analytical flow cytometry (FCM) is well suited for the analysis of phytoplankton communities in fresh and sea waters. The measurement light scatter autofluorescence properties particles by FCM provides optical fingerprints, which enables different groups to be separated. A submersible version CytoSense cytometer (the CytoSub) has been designed situ autonomous sampling analysis, making it possible monitor at a short temporal scale obtain accurate information about its dynamics. For...
In this study, we examined the possibility of using FluoroProbe for monitoring dynamics Haptophyte Phaeocystis globosa in coastal waters eastern English Channel. The was recalibrated by recording a new fingerprint P. and use tested through series laboratory situ experiments. annual estimated flow cytometry were similar. A strong relationship found between estimates biomass expressed terms chlorophyll equivalent per litre (eq. µg L−1) cytometric cell counts (r = 0.889, P < 0.001, n 121). can...
Abstract. Fine-scale physical structures and ocean dynamics strongly influence regulate biogeochemical ecological processes. These processes are particularly challenging to describe understand because of their ephemeral nature. The OSCAHR (Observing Submesoscale Coupling At High Resolution) campaign was conducted in fall 2015 which a fine-scale structure (1–10 km∕1–10 days) the northwestern Mediterranean Ligurian subbasin pre-identified using both satellite numerical modeling data. Along...
Abstract. Ice-nucleating particles (INPs) have a large impact on the climate-relevant properties of clouds over oceans. Studies shown that sea spray aerosols (SSAs), produced upon bursting bubbles at ocean surface, can be an important source marine INPs, particularly during periods enhanced biological productivity. Recent mesocosm experiments using natural seawater spiked with nutrients revealed INPs are derived from two separate classes organic matter in SSAs. Despite this finding, existing...
Abstract. The organic mass fraction from sea spray aerosol (SSA) is currently a subject of intense research. majority this research dedicated to measurements in ambient air. However number studies have recently started focus on nascent aerosol. This work presents collected during 5-week cruise May and June 2017 the central western Mediterranean Sea, an oligotrophic marine region with low phytoplankton biomass. Surface seawater was continuously pumped into bubble-bursting apparatus generate...
Gross community production (GCP), dark respiration (DCR), and the biomass of different size classes organisms in microbial were measured northeastern Atlantic basin as part Programme Océan Multidisciplinaire Méso Echelle (POMME) project. The field experiment was conducted during three seasons (winter, spring, late summer–fall) 2001. Samples collected from four mesoscale structures within upper 100 m. GCP rates increased winter (101 ± 24 mmol O 2 m −2 d −1 ) to spring (153 27 then decreased...
Abstract. The basin-scale distribution of ultraphytoplankton (<10 μm) was determined in the upper 200 m eastern Mediterranean Sea during winter season. Four clusters were resolved by flow cytometry on basis their optical properties and identified as Synechococcus, Prochlorococcus, pico- (<3 nanoeukaryotes (3–10 μm). Synechococcus most abundant population (maximum abundance about 37 000 cells cm−3) contributed up to 67.7% overall ultraphytoplanktonic carbon biomass, whereas contribution...
Abstract The variability of phytoplankton distribution has been unraveled by high‐frequency measurements. Such a resolution can be approached automated pulse‐shape recording flow cytometry (AFCM) operating at hourly sampling resolution. AFCM records morphological and physiological traits as single‐cell optical pulse shapes that used to classify cells into functional groups (PFGs). However, the associated manual post‐processing data coupled with increasing size number datasets is...