Seagrasses and mangroves can suck carbon from the air

OFF THE coast of Formentera, an island in the Spanish Mediterranean, lives an organism that stretches 15km from one end to the other. , more prosaically known as seagrass, spreads by sending shoots out beneath the sediment. Entire meadows, covering several hectares, can thus be made up of a single organism. The grasses are long-lived, too. The vast meadow in Formentera is thought to have been spreading for tens or hundreds of thousands of years.But the seagrass is more than just a biological curiosity. Along with two other kinds of coastal ecosystem—mangrove swamps and tidal marshes—seagrass meadows are particularly good at taking carbon dioxide from the air and converting it into plant matter. That makes all three ecosystems important for efforts to control climate change.