Multiscale modelling of hydro-biogeochemical fluxes along the Danube delta-Black Sea land-sea continuum

The Danube River is the second longest river in Europe. It passes through 10 countries before emptying in the Black Sea. The Danube Delta, largest nearly undisturbed wetland in Europe, plays a buffering role between the river and the sea. Eutrophication in the coastal zone due to the increase of nutrients coming from the river causes important biological and financial losses since the 1970s. However, despite this and the importance of the Danube-Danube Delta-Black Sea system, the hydro and biogeochemical fluxes in this system remain largely understudied. The main objective of this PhD is to model and quantify the interactions between the Danube delta and the Black Sea, from hourly to multi-annual time scales. More specifically, we aim to evaluate how the biogeochemical fluxes of the North-western shelf (NWS) (i.e. limited by the 100m isobath) impact and are impacted by the small-scale variability of the three branches of the Danube Delta (i.e. Chilia, Sulina and Sfântul Gheorghe).