Most of us don’t think much about seagrass. Sure, it helps stabilize the ocean floor, maintains water quality, and houses and feeds a ton of marine life, but since we can’t use seagrass to wrap a spicy-tuna roll most people never come into contact with it. Robert Orth, a marine biologist at the Virginia Institute of Marine Sciences, or VIMS, is not like most people. He’s been thinking about seagrass daily for over 20 years, and for good reason: seagrass captures and stores a massive amount of carbon. And, as you may have heard, excess carbon in the environment is resulting in deteriorating ecosystems and climate chaos across the globe.
According to the UN Environment Programme, although seagrass only occupies 0.2% of the ocean floor, it accounts for 10% of the ocean’s capacity to store carbon. In fact, it’s such an effective carbon sink, that it’s estimated to be 35x more efficient than tropical rainforests. Simply put, the more seagrass there is, the less carbon there is circulating freely in the ocean. Given its carbon sequestering capability, planting more seagrass could be an effective way of combating climate change.
“Great,” you’re probably thinking. “Let’s plant more seagrass and put an end to this whole climate chaos thing in a few weeks.” The problem is seagrass can be highly vulnerable if water quality conditions aren’t met. For example, in the 1930’s a disease caused by slime mold swept the eastern seaboard and decimated large amounts of a type of seagrass called eelgrass. That loss had radical implications on the ecosystem and its biodiversity, removing species like bay scallops from the biome. For decades scientists believed the eelgrass couldn’t be regrown, but in 1990 small patches of it were discovered off the coast of Virginia.
This discovery led Robert Orth to start a series of experiments in collaboration with the University of Virginia, first transplanting eelgrass from other areas into the bay in 1999. Once the eelgrass survived, Orth and his team began scattering seeds across a total of four bays: South Bay, Cobb Bay, Spider Crab Bay, and Hog Island. Not only did the seeds grow into plants, the plants thrived and spread. South Bay even successfully reintroduced bay scallops for the first time in nearly a century.
In the years since that first experiment, Orth’s operation has grown significantly. Aided by volunteers, his team has sown nearly 75 million seeds, blanketing six thousand acres of coastal bay in eelgrass and earning Orth a moniker: “The Johnny Appleseed of seagrass.” Ocean restoration groups across the world have looked to VIMS for guidance. Groups in other countries that have experienced similar seagrass loss, like the UK, Denmark, and Australia, are using VIMS research to guide their own restoration projects. Given how delicate seagrass life can be, not every experiment is likely to succeed, but, according to Orth, even the experiments that fail “help us move closer to our ultimate goal, which is not just getting seeds from a single species of seagrass to grow into adult plants, but rather to restore a community of plants and animals that persists through time.”
Meanwhile VIMS is hoping to build on their established success and restore all of the Eastern Coastal bays to their pre-1930 conditions. Doing so would mean cleaner, clearer oceans with more biodiversity, as mollusks, crustaceans, sea turtles, bottle-nosed dolphins and many more marine animals rely on seagrass to live. It would also mean much less carbon in the environment, and better defense from extreme weather, since coastal beds with seagrass are much less vulnerable to wave action from ocean currents and storms. Planting seagrass may not get us to carbon neutrality alone, but innovations like Orth’s, which protect and restore our environment, are essential contributors in the fight against climate change.
