Today’s factismal: Seagrass absorbs more CO2 per square foot than rain forests do.
If you are an adult shark, you spend a lot of your time eating. But if you are a baby shark, you spend a lot of your time hiding from things that would like to eat you. And there are two places that sharks a(and other fish) hide best: in the roots of mangrove forests and in thick seagrass. If you’ve never heard of seagrass, don’t worry – you aren’t alone! It is one of those unsung heroes of the ecosystem that nobody (except marine biologists) notices until it is gone. And yet, seagrass is one of the most important things on Earth!
It provides a hiding place and food for mollusks, small fish, crabs, and even huge dugongs and manatees! Not only does seagrass provide a sanctuary for little fish, it also helps stabilize sea floors and provides food for many animals. Seagrass grows on shallow muddy and sandy bottoms, changing them from places filled with muck to havens filled with life. Seagrass slows down the water that washes over it which causes the sediment to fall to the bottom where it is anchored by the seagrass roots. That sediment is mostly mud and fine sand that would choke the gills of small fish and cut off the light from small plants if it weren’t turned into useful sea bottom.
And the root of that bounty is the photosynthesis that seagrass does. By living in the shallow water, it is able to take advantage of the abundant sunlight and nutrients to grow rapidly. And that rapid growth means that it also stores CO2 rapidly; some biologists estimate that seagrass absorbs more than twice as much CO2 per square foot than a rain forest would. All told, seagrass absorbs about 1/8th of the CO2 that goes into the ocean, making it one of the world’s greatest tools for fighting climate change and species loss.
Unfortunately, we are losing seagrass. Overuse of fertilizers, soil loss from farming, and shoreline development have reduced the amount of seagrass by more than 12,000 square miles – that’s about the size of Maryland! Fortunately, there is a citizen science opportunity to help. Seagrass Watch is looking for people to report on the state of the seagrass that they see. To take part, head on over to: