THE OCEANIC POSIDONIA
The largest and longest living organism in the world
An essential marine plant
Although its appearance and its location at the bottom of the sea could make us think that it is an algae, Oceanic Posidonia is a superior plant and probably the most important plant in the Pitiusas marine ecosystem.
If something stands out above all in the landscape of the coast of Formentera, it is the crystalline waters that surround the island and this is thanks to the presence of the immense meadow of Oceanic Posidonia that plays the role of natural purifier. Its ecological importance is such that in 1999 it was declared World Heritage by UNESCO.
Unlike algae, it has leaves, stem and roots, in addition to producing flowers and fruits. It grows both in rocky funds and in mobile funds, that is, sandy, while algae only do so in hard or rocky bottoms.
We can find it between the surface level up to 30-40 meters deep depending on the transparency of the waters, occupying large areas in the Mediterranean coast.
The Balearic Islands have an area of 55,795 hectares of Posidonia grassland, of which 7,650 hectares correspond to the waters of Formentera. This translates into 76.5 million square meters to protect only in Formentera.
One of the most outstanding characteristics of this plant is that it is fixed to the substrate through rhizomes capable of extending several kilometers, producing millions of plants from the same clone. Posidonia specimens separated more than 15 kilometers from the same plant have been found, which has led scientists to estimate the age of this plant at 100,000 years, being the longest living being on the planet.
This plant plays an important role in sedimentary dynamics, since they keep the sediment still with its roots and creates important areas of oxygen production, breeding and refuge of many animal species. Its presence allows many marine species to establish their home in the waters of Formentera. It is estimated that more than 400 plant species and 1,000 animals inhabit the posidonia meadows. On the other hand, the prairies function as large filters, helping to keep the sea water clean and transparent. Likewise, the posidonia berms in the sand prevent erosion of the beaches.
Posidonia, so essential to maintain the biodiversity of the Mediterranean Sea, is cataloged by CITES and included in the List of Wild Species under Special Protection Regime in the Mediterranean.
Unfortunately, the Mediterranean Sea is the most overexploited on the planet and scientists keep asking themselves, what can we do to ensure its survival? The Posidonia, an endemic aquatic plant of Mare Nostrum, could be the key to its recovery.