Why are seagrasses important to the environment

Green sea turtle. Seagrasses stabilize sediments. Photo courtesy Florida Keys National Marine Sanctuary Seagrasses stabilize bottom sediments with their dense roots and rhizomes that form a secure mat.

Water Clarity Seagrass take up dissolved nutrients and trap sediments in the water resulting in high water clarity. Clear waters over seagrass habitat. Photo courtesy U. Further decomposition releases nutrients such as nitrogen and phosphorus , which, when dissolved in water, are re-absorbed by seagrasses and phytoplankton. Nursery areas: The relative safety of seagrass meadows provides an ideal environment for juvenile fish and invertebrates to conceal themselves from predators. Seagrass leaves are also ideal for the attachment of larvae and eggs, including those of the sea squirt and mollusk.

Much of Florida's recreationally and commercially important marine life can be found in seagrass meadows during at least one early life stage. Habitat: While seagrasses are ideal for juvenile and small adult fish for escape from larger predators, many infaunal organisms animals living in soft sea bottom sediments also live within seagrass meadows. Species such as clams, worms, crabs, and echinoderms, like starfishes, sea cucumbers, and sea urchins, use the buffering capabilities of seagrasses to provide a refuge from strong currents.

The dense network of roots established by seagrasses also helps deter predators from digging through the substratum to find infaunal prey organisms. Seagrass leaves provide a place of anchor for seaweeds and for filter-feeding animals like bryozoans, sponges, and forams. Water Quality: Seagrasses help trap fine sediments and particles that are suspended in the water column, which increases water clarity. They can filter pathogens, bacteria, and pollution out of seawater, and are home to endangered and charismatic species such as dugongs, seahorses, and sea turtles.

Since the late 19th century, almost 30 per cent of known seagrass area across the globe has been lost. The main threats to seagrass meadows include urban, industrial, and agricultural run-off, coastal development, dredging, unregulated fishing and boating activities, and climate change. The report, launched on World Oceans Day , finds that seagrass ecosystems play an outsized role in combatting the climate crisis.

Though they cover only 0. Countries aiming to do their part under the Paris Agreement can include seagrass protection and restoration in their nationally determined contributions NDCs to help reduce the amount of heat-trapping carbon in our atmosphere. As the global community works to build back better and strengthen economies and societies in the wake of the devastation wrought by this pandemic, preserving and restoring seagrass ecosystems can be a highly effective way to protect food chains and create jobs in industries such as fishing and tourism.

The well-being of human communities all around the globe is closely tied to the health of seagrass meadows. In Tanzania, a decline in seagrass was found to have a negative impact on the livelihoods of women who collect invertebrates, such as clams, sea snails and sea urchins, from seagrass meadows.

In the North Atlantic, seagrass provides critical habitat to juvenile Atlantic cod, a major commercial species that is fished by fleets from more than a dozen nations.