Posidonia, a marine plant
Posidonia oceanica is not an alga, but a marine flowering plant that lives only in the Mediterranean Sea. It forms meadows, real underwater forests that can be found at depths of up to 40 meters.
A major role against erosion
The banquettes that form on the beaches from dead Posidonia leaves deposited by the sea support biodiversity and play a major role in limiting beach erosion.
An ecosystem on its own
Posidonia meadows offer support, shelter, spawning grounds and nurseries for many species. More than 400 different plant species and several thousand animal species live there