If you’ve ever stumbled knee-deep into the brown muck around a mangrove forest, a salt marsh, or a batch of sea grass, then you’ve sunk into what scientists call a blue carbon sink — the carbon that’s stored by plants and trees along the edges of our coastal ecosystems.
And blue carbon sinks could be just as important as forests when it comes to managing our global carbon emissions, according to a new study by Nature Conservancy scientist Elizabeth Mcleod and published in the journal Frontiers in Ecology and the Environment. But Mcleod and her co-authors say science needs to learn a lot quickly about blue carbon sinks — because they’re disappearing fast.
Approximately one-third of the world’s mangrove, sea grass, and salt marsh areas have been lost over the past several decades. Because they hold so much carbon, say the researchers, destroying them could turn these blue carbon sinks into carbon sources.
Why are the briny plants and trees of these coastal habitats so good at storing carbon? Because the root systems of mangroves, salt marshes, and sea grasses have adapted to constant exposure to the tides by “learning” to build and maintain carbon-rich sediment — a process that doesn’t occur on land.
But Mcleod and her co-authors say too little is known about blue carbon for it to be accurately accounted for in global carbon markets. They call for science to measure and map blue carbon sinks and how they store carbon differently, so that conservationists and communities prioritize areas for conservation and protection.
“We see all the potential, but we can’t over promise until we address these knowledge gaps,” said Mcleod. “ Blue carbon could provide incentives to protect coastal ecosystems and improve the lives of local communities, but we need to do it right, with the right science backing it.”
(Image:Spanish Harbor Key: Mangrove Ecosystem, Florida Keys. Image credit: 1stpix /Flickr through a Creative Commons license.)