The first 6 months will be dedicated to the organization of the workshops in the estuary of Bach Dang.
The 1st workshop will be carried out in the rainy season (July/August 2008) and the 2nd workshop in the dry season (February/March 2009). These approaches will aim to identify the polluting sources, to characterize the processes of transport and to characterize the microbial communities (phytoplankton, bacteria, viruses) in relation to the physical (circulation) and environmental (nutrients, contaminants, particles) constraints.
A monthly survey of the anthropogenic contaminants and microbial communities (phytoplankton, bacteria, and viruses) will be carried out from April 2009 to April 2010 in order to characterize these parameters on an annual basis. The stations will be defined according to the spatial characterization carried out during the 2 workshops. It will be carried out either under the responsibility of IRD personnel in Vietnam, or under that of the Vietnamese partners after formation.
Experiments to describe the potential variations of the processes of aggregation/sedimentation along the gradient of salinity, and that so as to determine the fate of elements associated with the aggregates.
Experiments in controlled conditions (bioassays) will be carried out to evaluate if it is possible to determine the impact of the contributions of particles, nutrients and xenobiotics on the structure and the activity of the microbial communities.
Lastly, the measurements carried out during the 2 workshops will make it possible to validate a hydro-sedimentary 3D model from the estuary to the coastal zone, which will be used as support for the analysis of the fate and the transformation of the particles in the salinity gradient (flocculation and settling). It will allow later testing of scenarios of hydrological and anthropogenic changes in the estuarine hydrosystem.