SAZOOTOX 1
| Type | Oceanographic cruise |
|---|---|
| Ship | Sepia II |
| Ship owner | CNRS |
| Dates | 24/05/2004 - 27/05/2004 |
| Chief scientist(s) | SOUISSI Sami |
LABORATOIRE D'OCÉANOLOGIE ET DE GÉOSCIENCES - UMR 8187 28 avenue Foch BP 80 62930 Wimereux +33(0)3 21 99 29 00 |
|
| DOI | 10.17600/4440010 |
| Objective | A multidisciplinary group was recently created in the framework of the Seine-Aval program. It is working on the biological model Eurytemora affinis. This copepod species can reach high densities, exceeding those in other European estuaries by an order of magnitude. This key species of the estuarine ecosystem appears to be well adapted for life in an environment with strong hydrodynamics, and is capable of staying in the very highly contaminated oligo- and mesohaline zone of the estuary (on the margin of the turbidity maximum). Our recent results show that the preservation of the E. affinis population in the Seine estuary involves overlapping of several processes taking place on different space and time scales. The survey's objectives are to conduct high frequency studies of the couplings between physical, chemical and biological processes in this estuary. The main aim is to study the principle patterns of variability of the species with respect to tide and depth. We also divided the population into two stages: i) young stages which behave like passive particles, and ii) older stages which show migratory behavior in the vertical plane. Thus, all the processes highlighted should influence both the 1) contamination dynamics and ii) the food web and bioaccumulation dynamics. On a seasonal scale, the maximum abundance of E. affinis observed in the months of May-June corresponds to a rise in temperature. That is why we targeted that time of year for this application. Along with the novel approach of the planned studies, enabling three teams from different fields to work in collaboration, several scientific results are expected. We hope to provide a more complete image of biophysical and chemical interactions and contribute to improving process models. |
