Endemic sea plant of the Mediterranean Sea, it forms extensive underwater meadows that constitute one of the most important and productive ecosystems of the sea. In the Sinis Marine Protected Area, Posidonia oceanica meadows cover large areas in zones B and C and represent a priority habitat protected by Habitat Directive 92/43/EEC.
It produces oxygen, stabilises the seabed, protects the coast from erosion and provides shelter for numerous species of fish and invertebrates. The accumulations of leaves washed ashore (banquettes) play a fundamental ecological role.
