Seagrass and Climate change.

HAVE YOU EVER HEARD OF SEAGRASS?

Seagrass is a wonder-plant that lives in shallow, sheltered areas along our coast. It is vital to the health of our seas and can help address environmental problems. Seagrass captures carbon up to 35 times faster than tropical rainforests and, even though it only covers 0.2% of the seafloor, it absorbs 10% of the ocean’s carbon each year, making it an incredible tool in the fight against climate change. Seagrass is vital for marine life, which depends on the meadows for food and shelter. A 10,000m2 area can support 80,000 fish and over a million invertebrates. Seagrass is an important nursery for endangered wildlife such as seahorses, as well as many of the fish we eat, including cod, plaice and pollock.

Restoration of these habitats can count towards national climate-change plans. Each signatory to the Paris Agreement is required to submit its plan, or nationally determined contribution, to the United Nations, with successive plans becoming more ambitious.

The potential for seagrass in nationally determined contributions is significant, as some 159 countries have seagrass on their shores. An analysis soon to be published by GRID-Arendal, a Norwegian foundation working with the United Nations Environment Programme (UNEP), found that 10 countries have included seagrass in existing nationally determined contributions. Five countries refer to its conservation and restoration in mitigation actions, while eight plan to use it in adaptation.

Seagrasses have survived, not just as species, but often as individual clones, for thousands of years. Scientists studying Posidonia oceanica meadows in the Mediterranean Sea estimate that the largest clone, which stretches more than nine miles, has been around, sending out slow-growing rhizomes, for tens of thousands of years, and possibly as many as 200,000 years. It could be the oldest-known organism on Earth.

seagrasses are capable of capturing and storing a large amount of carbon from the atmosphere. Similar to how trees take carbon from the air to build their trunks, seagrasses take carbon from the water to build their leaves and roots. As parts of the seagrass plants and associated organisms die and decay, they can collect on the seafloor and become buried, trapped in the sediment. It has been estimated that in this way the world's seagrass meadows can capture up to 83 million metric tons of carbon each year. The carbon stored in sediments from coastal ecosystems including seagrass meadows, mangrove forests and salt marshes is known as "blue carbon" because it is stored in the sea. While seagrasses occupy only 0.1 percent of the total ocean floor, they are estimated to be responsible for up to 11 percent of the organic carbon buried in the ocean. One acre of seagrass can sequester 740 pounds of carbon per year (83 g carbon per square meter per year), the same amount emitted by a car traveling around 3,860 miles (6,212 km).

Like many other ecosystems, seagrasses are also facing rapid decline. Approximately 7 percent of global seagrass coverage disappears each year, similar to the loss of coral reefs and tropical rainforests. This decline also threatens species that depend on seagrasses for food and habitat, including endangered manatees, green sea turtles, chinook salmons, and dugongs, and it serves as a warning of greater devastation to come.