Seagrass, in particular Posidonia oceanica, plays an important role in the ecosystem and provides several services. It ensures the maintenance of physical, chemical and biological conditions. It provides a habitat for many different species, is a nursery, hunting and predator area. Furthermore, it mediates flow, is a coastal erosion protection by stabilizing the sea beds and it decreases the water power and current. Seagrass provides regulation and maintenance services like water purification by filtration, sequestration of nutrients and contaminants (Campagne, Salles, Boissery, & Deter, 2014). Because of its ecological importance and vulnerability to a variety of anthropogenic influences, there is an increasing interest in using P. oceanica as an indicator of the health of the Mediterranean coastal systems (Balestri, Cinelli & Lardicci, 2003).