How many times have we found Posidonia lying in the sea like a prairie and how many times dry on the beach?

Every time we have to drop the anchor, I, who am at the bow of the boat, look under the sea to see if there is Posidonia in order to find a space free from it to be able to start the descent of the anchor. This attention is also part of our eco-sustainable philosophy.

Posidionia Oceanica represents an endemic species of the Mediterranean Sea of great ecological value and constitutes one of the most important and biodiversity-rich ecosystems of our sea. Posidonia is a source of oxygen and a refuge for numerous marine species; they constitute precious areas of reproduction, development, nourishment and refuge for a large number of marine organisms that feed, reproduce, lay their eggs and grow here.

Furthermore, being a plant, it produces oxygen , offers refuge to numerous species as well as slowing down the wave motion, protecting both the seabed and the coasts from erosion.

It can colonize large areas of seabed generally between 30 and 50 m deep.

It tolerates notable temperature variations between 10°C and 28°C but is particularly sensitive to variations in salinity. For this reason it is also considered a fundamental ecological indicator for the study of variations in environmental conditions.

This is why it is essential to preserve it.

Nowadays the presence of Posidonia banks on the beach is associated with an obstacle for tourists, which is why it is often removed without due precautions. It is not taken into account that in addition to protecting the sandy coasts, the banks of Posidonia are real plant structures that host complex ecosystems.

Posidonia is the subject of laws for its protection:

• Posidonia has been considered a priority ecosystem by the European Community with Directive No. 43/92 EEC relating to the " conservation of natural and semi-natural habitats and wild flora and fauna ", implemented into Italian law by Presidential Decree No. 357 dated 09/08/1997.
• Posidonia oceanica is a protected species as it is included in Annex II (published in the ordinary supplement to the official gazette SG n° 146 dated 24/06/99) to the Bern Convention of 19/11/1979 relating to the " Conservation of wild life of the natural environment in Europe ” ratified in Italy with law n° 503 of 05/08/1981 (published in the official gazette n° 250 of 11/9/1981).
• Posidonia oceanica is included in Annex II to the 1995 Barcelona Convention for the protection of the Mediterranean from pollution, ratified in Italy with law no. 175 of 05/27/99.

The protection of Posidonia is of considerable importance because:

• preserves fish productivity
• preserves the seabed and sandy coasts from erosion
•  

Some of the threats to Posidonia meadows are obviously represented by human interventions such as:

• the scraping of the anchors of pleasure boats which are thrown onto the seabed covered with posidonia
• trawling , capable of removing and destroying entire pieces of prairie; 
• the concreting of the coasts (construction of roads, ports, consolidations, sand extraction);
• pollution from chemicals spilled into the sea
• climate change which brings variations in the sea to which the plant is sensitive

This is why Lasca la Randa with Vela Trekking is committed to preserving the Posidonia meadows.

Mare Vivo has raised considerable awareness about the protection and safeguarding of Posidonia, with targeted activities starting in 1990 which have contributed to making it a protected species (infographic image by Marevivo.it).