Axis 4: Impact of deposition of mineral atmospheric dust on marine ecosystems

Some elements (N, Fe, P, Si, Co, Zn...), essential to the development of phytoplankton, are sometimes limited in the marine environment. Therefore, in some remote ocean areas, the atmospheric deposition is a major source of these nutrients. Knowing the chemistry of these metals and metalloids is critical to accurately estimate their bioavailability in the marine environment, that is, the fraction which is solubilized. After having extensively documented this chemistry in clouds, our priorities concern now the fate of atmospheric deposition in the oceans.

The studies, conducted in collaboration with the oceanographic community, are primarily based (i) on experimental approaches in the laboratory whose goal is to study the dissolution process of mineral aerosols and (ii) on field campaignsin which the main physico-chemical characteristics of aerosols and the atmospheric deposition are measured. The marine regions studied in priority are the Austral Oceans and the Mediterranean Sea.

The study of the role that mineral aerosol play as a source of nutrients (Fe, P) for the marine environment and the quantification of their contribution compared to other types of aerosols (aerosol from pollution, biomass burning …) is one of our objectives in the Mediterranean CHARMEX project.

=> Study of the dissolution process of the nutrients in contact with water

=> Evaluation of the deposition fluxes to the oceans and its variability