All over the world, seagrasses have been estimated to cover between 0.15 and 4.6 million square kilometers, an area ten times bigger than the Red Sea. The Red Sea itself hosts 12 of the 60 species of seagrasses present all over the world, and together these seagrasses form an area that extends for more than 100,000 square kilometers, similar the total size of Portugal.
Seagrass meadows, with their leaves extending toward the seawater surface, slow down the marine currents that transport sediment and other particles and allow the settling of this sediment among the roots and leaves of the seagrass. By doing this, seagrasses help to form new layers of sediment on top of the older ones. But how do seagrasses avoid being buried? The trick is in their extraordinary level of adaptation, acquired by living in this constantly changing ecosystem: thanks to rhizomes, each single seagrass plant can adjust its growth and keep pace with sedimentation. By helping sediment to accumulate, seagrasses protect the coastline from erosion and therefore protect houses, roads, and cities built near the shore.

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