Posidonia oceanica is a seagrass endemic to the Mediterranean Sea, where it forms extensive meadows of high ecological value, providing key ecosystem services such as biodiversity maintenance, coastal protection and carbon sequestration. In recent decades these meadows have undergone a marked regression due to cumulative anthropogenic pressures and environmental changes, making effective conservation and restoration strategies increasingly urgent.
Among active restoration actions, the transplantation of P. oceanica cuttings has been tested using different anchoring techniques. However, restoration interventions based on similar techniques have often produced very different outcomes depending on the transplantation site, in terms of shoot density, anchoring stability and survival. These differences suggest that restoration success does not depend only on the adopted technique, but also on the environmental suitability of the selected site, intended as the combination of ecological and physical conditions that allow transplanted cuttings to remain stable, develop new roots and expand. Besides parameters that can be directly assessed, such as depth, substrate type or protection level, less readily observable hydrodynamic and physical factors, including bottom currents, storm-induced stress and seabed stability, may represent important mechanical constraints, especially during the early post-transplant phase.
This study proposes a preliminary hydrodynamic modelling approach aimed at supporting site selection for P. oceanica restoration. Using GIS tools, bathymetric and spatial data were processed to build input grids in Delft3D. Sanremo site was selected as the first case study due to the availability of data from previous restoration actions and monitoring activities. The proposed workflow aims to include quantitative hydrodynamic descriptors in restoration planning, helping to distinguish between ecological habitat suitability and the physical stability required for transplant persistence. This approach may support the selection of sites and anchoring techniques more consistent with local physical conditions, improving the use of resources and the effectiveness of restoration actions.