Models of relations between bacteria and plankton, and regeneration processes in marine planktonic ecosystem.

In order to study bacteria-plankton relationships, experimental and mathematical models were used to stimulate biological processes implicated in plankton ecosystems and to analyze community relationships. The model components are phytoplankton, zooplankton, autotrophic and heterotrophic bacteria, ciliates, nutrients, organic matter and phytoplankton antibiotics. This study shows the importance of some factors affecting bacteria communities dynamics and the bacterial activity in mineralization process. Bacterial populations seem to be controlled essentially by the concentration and chemical composition of organic substrates. Antibiosis and predation show a lesser importance on changes in bacteria communities.