Blue carbon refers to the carbon captured and stored by oceans and coastal ecosystems such as mangroves, seagrasses, and tidal marshes. These ecosystems are highly effective at sequestering carbon dioxide from the atmosphere and storing it in the form of organic matter in the soil and plant biomass. Blue carbon ecosystems can sequester carbon up to 10 times more efficiently per unit area than terrestrial forests, and their conservation and restoration can help mitigate climate change. The term "blue" carbon is used to emphasize the role of these ecosystems in capturing and storing carbon in the marine environment.