By: Sowmiya,C. and Atshaya, S. *
Seagrass meadows benefit aquaculture systems by providing water filtration, biological controls, and regulation of dissolved gasses. In addition, the seagrass dominated system oxygenates the water by photosynthesis faster than the respiratory oxygen consumption, and it helps to maintain the aquaculture system above the minimum oxygen level.
Seagrasses encourage various kinds of biota by producing considerable organic matter and providing primary energy sources in the coastal marine food web, notably inshore stabilization and nutrient regeneration processes.
In flow-through systems, the incoming water to the coastal water bodies is usually polluted by nutrients, suspended solids, and microorganisms. It requires quality control methods and treatment.
Seagrass meadows benefit aquaculture systems by providing water filtration, biological controls, and regulation of dissolved gasses. In addition, the seagrass dominated system oxygenates the water by photosynthesis faster than the respiratory oxygen consumption, and it helps to maintain the aquaculture system above the minimum oxygen level.
“Worldwide, 13 genera and 58 species of seagrass are reported; 14 species belonging to 6 genera are in India; 13 species are found in the Gulf of Manner Biosphere Reserve.”
Seagrasses are one of the most productive ecosystems in the world. They provide a nursery and breeding ground for many marine organisms. Seagrasses might improve the water quality of the flowing water used in the aquaculture system, decreasing the costs for water treatment.
Habitat
Seagrass meadows give an ideal environment for juvenile fish and tuck away the invertebrates from predators. The larvae and eggs of sea squirt and mollusk are attached to the leaves of seagrass. They bear anchor for seaweeds and filter feeding animals like bryozoans, sponges, and forams. They also act as a home to sharks, fish, mollusks, crustaceans, sea urchins, sponges, polychaete worms, and endangered species such as dugongs, seahorses, and sea turtles.
Natural Based solution
Natural based solutions could benefit coastal aquaculture systems to over come the water quality challenges, for instance, through the filtering provided by coastal vegetated ecosystems.
In shallow coastal water, seagrasses and marine flowering plants form extensive meadows that play a vital role in their nutrients cycling and water purification by filtration and acting as a natural biofilter in oyster farming.
Coastal protection
Seagrasses alter the ecosystem and its surroundings in both physical and chemical ways. Therefore it is called “ecosystem engineers.” The long blades of seagrasses decrease the wave energy by slowing down the movement of water.
“Seagrass meadows benefit aquaculture systems by providing water filtration, biological controls, and regulation of dissolved gasses.”
It also prevents coastal erosion and storm surge. The roots and rhizome of seagrasses form an extensive underground network that helps to stabilize sediment.
Blue carbon
In a coastal ecosystem such as seagrass meadows, mangrove forests, and salt marshes, carbon is stored in their sediments hence known as “Blue carbon”.
A large amount of carbon from the atmosphere can be captured and stored by the seagrasses, and they also use carbon to build their leaves and roots.
“A highly effective way to protect food chains can be made possible by the restoration of seagrasses.”
It has been reported that 83 million metric tons of carbon can be captured by the world’s seagrass meadows each year.
Stabilization
Seagrasses help to stabilize the sea bottom by their extensive root system, which extends both vertically and horizontally. It also prevents soil erosion. One meter of Seagrasses can create 10 liters of oxygen per day through photosynthesis.
Hence it is known as the “lungs of the sea” added they expand their expertise by controlling nutrient pollution caused by exogenous feeding in aquaculture.
Threats to seagrasses
Human activities lead to the losses of seagrass beds directly and indirectly in recent decades. Propellers and boat anchors make scars in a seagrass bed, killing sections of the seagrass and fragmentation habitat.
- Physical disturbance includes wind driven waves, and storms can damage the seagrasses.
- Nutrients from fertilizers and pollution wash off the land and enter the water, creating algae blooms that block sunlight for seagrass growth. Also, it damages seagrass beds by smothering the seagrass.
- Furthermore, the introduction of invasive seaweed species can replace native seagrass species. For example, invasive species like Caulerpa toxifolia (killer algae) has been released into the Mediterranean in the 1980s. By 2000 it surrounds more than 131 square kilometers of the Mediterranean coastline, overgrowing and displacing the native Neptune seagrass (Posidonia oceanica) and reducing the ecosystem biodiversity.
Conservation
A highly effective way to protect food chains can be made possible by the restoration of seagrasses. Also, it creates jobs in industries like fishing and tourism. Only 26 percent of seagrass meadows have been included in Marine Protect Area. This report indicates that seagrasses are among the least protected coastal habitats.
Conclusion
Seagrasses are considered a super ecosystem of our ocean. Because it is providing an incredible range of benefits to people around the world, with this restoration in practice, we can contribute to the U.N SDGs, Paris Agreement, and the Convention on Biological Diversity.
By taking simple steps, everyone can protect seagrass and other marine habitats. Be cautious while anchoring and trawling, limit fertilizer and pesticides usage, do not dump anything, and support the local conservation effort. You are what you eat; remember, no one is safe unless nature is safe.
*Sowmiya, C. Research Scholar, M.F.Sc, Department of Aquaculture, TNJFU-FCRI, Tuticorin, India. csowmiyasow-miya@gmail.com (Corresponding author ) Atshaya.S. Research Scholar, M.F.Sc, FNBP Division, ICAR-Central Institute of Fisheries Education, Mumbai, India. References used by the authors available under previous request to our editorial team.
