Particles are important in geochemical fluxes in the shelf margin in the North Western Mediterranean Sea. The microbial population attached to the particles are the major mediators of these biogeochemical processes. In order to understand the biogeochemical processes it is important to study the microbial processes occurring on particles in the natural environment.
The overall objective of this project is to investigate the microbial population dynamics on particles and the role of specific microbial processes in the biogeochemisrty of the water column. The spatial and/or temporal evolution of particle-attached bacteria will be measured in terms of budgets and fluxes in the ocean interior. The relative biomasses, the specific and physiological diversity of natural communities, and the autotrophic and heterotrophic bacteria activities in the particulate system will be compared with those of free-living microorganisms. Theoretical studies will be devoted to increasing the knowledge of the microbial mechanisms governing the dynamics of particulate systems, and reciprocally, to the protective role of particles. All data will be used for modelling the impact of attached microorganisms and aggregates on carbon flux in the water column, and on the particle distribution and remineralization.
The specific objectives of the research are:
1. Determination of microbial activates influencing biogeochemical cycles, and measurement of their rates.
2. Estimation of bacteria metabolic activities affecting the physical and chemical composition of particles (production of polymers, hydrolysis of macromolecules such as the degradation of chitin).
3. Determination of the composition of particulate matter.
4. Measurement of the vertical and horizontal distribution and associated changes in the state of activity of the attached microorganisms.
5. Assessment of the relative importance and taxonomy diversity of microbial communities colonising particulate material, according to the abundance, origin, chemical nature and spatial distribution in the water column of the particles.
6. To develop a model of studied processes related to the microbiology of the particles which will include the effects of fluctuating physical changes on activity of attached microorganisms.
Funding SchemeCSC - Cost-sharing contracts
PL1 3DH Plymouth
AB25 2ZD Aberdeen
4020 Jupille - Liège