Qualitative Approach of Plankton Communities Behaviour in a Mediterranean Bay : a Contribution to Some Biological and Mathematical Aspects

Seasonal variations of the plankton community (phytoplankton and zooplankton) in the Toulon Bay (Var, France) have been studied since 1995 [1, 2]. Plankton samplings have been carried out regularly in two sites (little bay and large bay) differently affected by anthropogenic inputs of Toulon area. The abundance and the diversity of plankton community during annual cycles have provided some data which exhibit inherent features as the pattern shape of limit cycles as well as the apparent period of intrinsic evolution of phytoplankton and zooplankton separately considered. We have also some data of average concentrations of nitrates and orthophosphates in the bays.