Modelling of biological and physical processes influencing biogenic sinking particles in the San Jorge Gulf (Patagonia, Argentina)

NOCERA, A.C.; DUMONT, D.; SCHLOSS, I.; FERREYRA, G. A.

Rimouski

Workshop; Workshop on the PROMESSe project: results and opportunities; 2017

UQAR-ISMER

Marin processes, such as the biological pump, modulate and influence the particulate organic matter (POM) flux towards seabed. Although the San Jorge Gulf (SJG) is one of the most productive areas of the world, only few works focused on vertical transport and carbon flux. In order to clearly understand organic matter production and its export in the water column of the SJG (Patagonia, Argentina), this thesis addressed two main questions: what is the influence of migrating organisms, such as zooplankton, and the influence of aggregation and transformation processes of particulate organic matter in the vertical carbon flux. The general hypothesis proposed here is that carbon flux will be affected by detrital dynamics, modifying ecosystems interactions and that this is strongly influenced by zooplankton active transport, as the main contributor of detritus. The use of numerical simulation gained a great interest in scientific research community for studying marine ecosystems dynamics and as a management tool. The first chapter presents the effect of a new parameterization of zooplankton diel vertical migration (DVM) in a 1D, coupled NPZD model. Both phytoplankton and detritus results show an increase in their concentrations, while zooplankton concentration decreases with the addition of the migration behavior. The second chapter presents a conceptual model of principal processes affecting different detritus types and the formulations, which will after allow coupling it with an Eulerian biogeochemical model to better simulate organic carbon flux and its role in the biological pump in the SJG.