Objective
TO QUANTIFY THE INFLUENCE OF METABOLIC ACTIVITIES OF PRINCIPAL CONSTITUENTS OF THE MICROBIAL COMMUNITIES ON THE DYNAMICS OF DIFFERENT FORMS OF NITROGEN AND CARBON IN MARINE ECOSYSTEMS.
THE BACTERIAL PARTICIPATION TO THE BIOGEOCHEMICAL CYCLES ON N AND C IN THE WATER AND THE SEDIMENTS OF MARINE ECOSYSTEMS WILL BE STUDIED ESTABLISHING EXPERIMENTAL ECOSYSTEMS OF MORE AND MORE COMPLEX STRUCTURE.
THE RESEARCH PROGRAMME WILL BE CARRIED OUT IN 3 PHASES:
1. DEFINITION OF THE STRUCTURE AND FUCTION OF BACTERIAL COMMUNITIES IN THE AQUATIC PHASE OF THE ECOSYSTEMS ONLY. DURING THIS PHASE EXPERIMENTS WILL BE DONE IN 350 L TANKS TO DEFINE METABOLIC POTENTIALITIES BY PURE CULTURE STRAIN STUDIES, HETEROTROPHIC ACTIVITIES USING 14C COMPOUNDS (RESPIRATION, ASSIMILATION, EXCRETION) AND THE EVOLUTION OF DIVERSITY OF BACTERIAL COMMUNITIES.
AT THE SAME TIME THE N CYCLE WILL BE FOLLOWED USING 15N AND SPECIFIC BACTERIAL ACTIVITIES (E.G. PROTEOLYSIS, AMMONIFICATION AND NITRIFICATION).
THE PRIMARY PRODUCTIVITY WILL BE CHARACTERISED BY STUDYING THE POPULATION OF THE DOMINANT ALGAE, THE PLANCTONIC BIOMASS (ATP, CHLOROPHYLL A) AND THE INDEX OF PIGMENTAL DIVERSITY. THE CELL ACTIVITY WILL BE MEASURED BY THEIR ELECTRICAL CHARGE AND BY THE AUTOTROPHIC POTENTIALITY (14BICARBONATE).
EACH STEP WILL BE SUBJECTED TO MATHEMATICAL MODELLING AND TECHNICS SUCH AS CONTINUOUS CULTURE WILL BE USED TO DEFINE PARAMETERS.
2. IN THE SECOND STEP THE EXPERIMENTAL DESIGN WILL BE REFINED, INTRODUCING SEDIMENTS INTO THE MODEL ECOSYSTEM. SAME KINDS OF ENRICHMENT EXPERIMENTS WILL BE CARRIED OUT. THIS WILL SHOW THE INFLUENCE OF THE SEDIMENT ON BACTERIAL ACTIVITIES AND THEIR EFFECTS ON N AND C CYLCES..
3. THE LAST STEP OF WORK WILL BE TO FOLLOW THE ACTIVITY OF BACTERIAL COMMUNITIES IN SEMI-NATURAL ECOSYSTEMS LIKE AQUACULTURE SYSTEMS.
Topic(s)
Data not availableCall for proposal
Data not availableFunding Scheme
CSC - Cost-sharing contractsCoordinator
75794 PARIS
France