POSIDONIA BENEFITS
CO2 sinks
One of the biological functions of Posidonia is the absorption of carbon dioxide. Part of the carbon will become part of the plant’s structures and biomass. Over time, a large part of this biomass dies and becomes buried in sediments under the prairie, within the plant. This carbon remains “sequestered” within the plant, accumulating over time. This helps mitigate the effects of CO2 as a greenhouse gas. “One hectare of Posidonia in Formentera sequesters as much carbon as 15 hectares of Amazon rainforest”.
Oxygenation
Posidonia meadows, as an ecosystem, generate high amounts of oxygen to the environment. Like any plant, they absorb CO2 and emit oxygen. It is estimated that one hectare of Posidonia in the Balearic Islands is capable of producing 5 times more oxygen than one hectare of the Amazon rainforest. It is the lung of the Mediterranean.
Transparent waters
The seagrass meadows prevent the lifting of sediment from the seafloor, stabilizing the substrate and maintaining clear, transparent waters. A large part of these substrates integrates with the rest of the dead rhizomes that accumulate over time and form the plant. In addition, their intolerance to changes that occur around them serves as an excellent indicator of water quality.
Biodiversity
The unique conditions of the Posidonia meadows provide essential habitats for a great diversity of marine species, including fish, crustaceans, mollusks, and other organisms. Many of these species take advantage of the nutrients and protection of the meadows to grow during their early life stages, when they are most vulnerable.
Dune Systems
The dunes define and protect the beaches from erosion. In winter, the accumulation of leaves along the beach, known as banquettes, stabilizes the sediment and reduces the effect of the waves on the coast. Additionally, the shells and carapaces of calcareous organisms and epiphytic algae on the leaves of Posidonia integrate into the accumulated substrate, creating whiter beaches.
Sand Generation
In the seagrass meadows, a large part of the white sand is produced. Much of it is formed by shells and calcareous structures of small organisms that live among the Posidonia. When these organisms die and settle in the meadow, over time they accumulate on the meadow itself or on the beach. The same meadow can form a small underwater reef elevation that forces the waves to break away from the beach, preventing erosion and keeping the sand from returning to the sea.
