Seagrass meadows are key ecosystems in the Mediterranean coastal areas supporting rich biodiversity and providing numerous ecosystem services. However, these ecosystems are increasingly threatened by local anthropogenic pressures and climate change. Because their natural recovery after disturbance is slow, active restoration – increasingly incorporating innovative methodologies - has become an important tool for their conservation. In this context, we investigated a facilitation-based interaction technique through an experimental restoration intervention within the “Capo Gallo–Isola delle Femmine” Marine Protected Area. The transplantation was carried out on a Posidonia oceanica matte substratum and involved 16 one-square-meter grids, arranged into four experimental units and randomly assigned to one of the following treatments: Cymodocea nodosa only, P. oceanica only, a combination of both P. oceanica and C. nodosa shoots, and a control grid (matte only). Transplant performance is being monitored monthly using non-destructive methods, combining classical biometric techniques with metabolic measurements. This experiment represents an innovative approach to the restoration of P. oceanica meadows, leveraging the potential facilitative role of C. nodosa to enhance restoration effectiveness through interspecific interactions. In addition, traditional monitoring is complemented by metabolic measurements at both individual and community levels, providing functional performance metrics. Although results are still under evaluation, this study offers a potentially replicable and methodologically advanced model for future restoration efforts, aiming to strengthen the resilience of Mediterranean coastal ecosystems.

Keywords: ecological restoration, Posidonia oceanica, Cymodocea nodosa, metabolism, biotic interactions