Assessing the spatial and temporal trophic properties of the Marano and Grado Lagoon, Italy with the coupled physical-biogeochemical model SHYFEM-BFM

Coastal and transitional areas worldwide are affected by a range of human pressures and are subjected to high natural variability. In the Marano and Grado lagoon, located in the densely anthropized north-eastern coastal area of Italy, the conservation of biodiversity and the presence of important socio-economic activities require planning and management tools and measures. Coupled physical and biogeochemical models are useful tools to support trophic studies in complex systems such as the Marano and Grado lagoon by integrating field information with relevant hydrodynamic and biogeochemical processes shaping the system. The coupled SHYFEM–BFM model was applied to the Marano-Grado lagoon, adding new features to account for the contribution of macrophytes (such as seagrasses). Results were validated against available in situ observations, and trophic properties were investigated using trophic state indices that allow to reproduce spatial and temporal variability under different scenarios.