A5058792942- Marine and coastal ecosystems
- Groundwater and Isotope Geochemistry
- Marine Biology and Ecology Research
- Methane Hydrates and Related Phenomena
- Ocean Acidification Effects and Responses
- Wastewater Treatment and Nitrogen Removal
- Microbial Fuel Cells and Bioremediation
- Hydrocarbon exploration and reservoir analysis
- Microbial Community Ecology and Physiology
- Geochemistry and Elemental Analysis
- Isotope Analysis in Ecology
- Geology and Paleoclimatology Research
- Mine drainage and remediation techniques
- Soil and Water Nutrient Dynamics
- Underwater Vehicles and Communication Systems
- Coastal wetland ecosystem dynamics
- Marine Bivalve and Aquaculture Studies
- Oceanographic and Atmospheric Processes
- Karst Systems and Hydrogeology
- Coral and Marine Ecosystems Studies
- Metal Extraction and Bioleaching
Université du Québec à Rimouski
2014-2017
Vrije Universiteit Brussel
2014-2015
Max Planck Institute for Marine Microbiology
2010-2012
Woods Hole Oceanographic Institution
2007-2011
Max Planck Society
2010
Skidaway Institute of Oceanography
2004-2008
Abstract Recently, a novel mode of sulphur oxidation was described in marine sediments, which sulphide deeper anoxic layers electrically coupled to oxygen reduction at the sediment surface. Subsequent experimental evidence identified that long filamentous bacteria belonging family Desulfobulbaceae likely mediated electron transport across centimetre-scale distances. Such long-range transfer challenges some long-held views microbial ecology and could have profound implications for cycling...
Filamentous sulfide oxidizing cable bacteria are capable of linking the oxidation free in deep anoxic layers marine sediments to reduction oxygen or nitrate surface by conducting electrons over centimeter-scale distances. Previous studies have shown that this newly discovered microbial process, referred as electrogenic (e-SOx), may alter elemental cycling sediments, but nature and rates resulting biogeochemical transformations their influence on benthic-pelagic coupling remain largely...
Porewater profiles and sediment-water fluxes of oxygen, nutrients, pH, calcium, alkalinity, sulfide were measured in intertidal sandflat sediments from the Oosterschelde mesotidal lagoon (The Netherlands). The influence bioturbation bioirrigation by deep-burrowing polychaete Arenicola marina on rates sources benthic alkalinity generation was examined comparing measurements intact defaunated sediment cores before after addition A. summer fall 2011. Higher organic matter remineralization...
To investigate diel calcium carbonate (CaCO 3 ) dynamics in permeable coral reef sands, we measured pore‐water profiles and fluxes of oxygen (O 2 ), nutrients, pH, (Ca 2+ alkalinity (TA) across the sediment‐water interface sands different permeability at Heron Reef, Australia. Background flushing rates were high, most likely as a result infaunal burrow irrigation, but flux chamber stirring enhanced exchange. Light advection fueled high benthic primary production calcification sunlit surface...
Abstract. The transformations of chemical constituents in subterranean estuaries (STEs) control the delivery nutrient loads from coastal aquifers to ocean. It is important determine processes and sources that alter concentrations at a local scale order estimate accurate regional global fluxes via submarine groundwater discharge (SGD), particularly boreal environments, where data are still very scarce. Here, biogeochemical nitrogen (N) species were examined within STE microtidal sandy beach...
RAO, A.M.F. and CHARETTE, M.A., 2012. Benthic nitrogen fixation in an eutrophic estuary affected by groundwater discharge.Anthropogenic nutrient loading of coastal aquifers has resulted the discharge nutrient-enriched to zone, with sweeping repercussions on aquatic community structure ecosystem function. Groundwater-derived is known initiate eutrophication, hypoxia, harmful algal blooms. However, most land-derived inputs ocean are thought be removed heterotrophic estuarine sediments, which...
Continuous, 7 year records of above‐water, near‐surface water column and near‐bottom measurements photosynthetically active radiation (PAR) were used in conjunction with situ chamber to estimate magnitude seasonal variations benthic primary productivity (BPP) on the Georgia continental shelf. Correlation between BPP PAR flux was established 19 light/dark at depths from 14 40 m. No substantial improvement relationship is observed by inclusion chlorophyll biomass temperature, apparently...
Abstract The paper presents evidence of the complexity describing carbon transport from submarine groundwater discharge and chemical reactions in subterranean estuary. Vertical horizontal profiles total alkalinity (TA) dissolved inorganic (DIC) concentrations were analyzed a cross-shore transect sandy beach an evaluation DIC TA fluxes to coastal waters is proposed based on velocities hydrogeology. study was conducted Magdalen Islands Gulf St. Lawrence (QC, Canada) where unconfined sandstone...
Measurements of porewater O2, pH, and H2S microprofiles in intact sediment cores collected a northern saltmarsh the St. Lawrence Estuary (Quebec, Canada) revealed occurrence electrogenic sulfur oxidation (e-SOx) by filamentous "cable" bacteria submerged marsh pond sediments high marsh. In summer, geochemical fingerprint e-SOx was apparent cores, while fall, cable were detected fluorescence situ hybridization characteristic signature observed only upon prolonged incubation. exposed,...
A numerical model of NaBr tracer transport in benthic flux chamber incubations has been developed to simulate temporal changes water concentrations and applied four deep sea locations: the California North Carolina margins, Ceara rise, Cape Verde plateau. Model variables include volume (which determines initial concentration), rates diffusive nonlocal exchange across sediment‐water interface. Chamber solute rate estimates were obtained by optimizing fit between observations results using a χ...
Abstract. The transformations of chemical constituents in subterranean estuaries (STE) control the delivery nutrient loads from aquifers to coastal ocean. It is important determine processes and sources that affect concentrations at a local scale order accurately estimate global fluxes via submarine groundwater discharge (SGD), particularly boreal environments, where data are still very scarce. Here, biogeochemical nitrogen (N) species were examined within STE microtidal sandy beach located...