Seagrasses are a vital part of the solution to climate change and, per unit area, seagrass meadows can store up to twice as much carbon as the world's temperate¹ and tropical forests. So report researchers publishing a paper this week in the journal Nature Geoscience.

The paper, "Seagrass Ecosystems³ as a Globally Significant Carbon Stock," is the first global analysis of carbon stored in seagrasses.

The results demonstrate that coastal⁴ seagrass beds store up to 83,000 metric tons of carbon per square kilometer, mostly in the soils beneath them.

As a comparison, a typical terrestrial（陆地的） forest stores about 30,000 metric tons per square kilometer, most of which is in the form of wood.

The research also estimates that, although seagrass meadows occupy less than 0.2 percent of the world's oceans, they are responsible for more than 10 percent of all carbon buried annually⁵ in the sea.

"Seagrasses only take up a small percentage of global coastal area, but this assessment⁶ shows that they're a dynamic ecosystem² for carbon transformation," said James Fourqurean, the lead author of the paper and a scientist at Florida International University and the National Science Foundation's (NSF) Florida Coastal Everglades Long-Term Ecological⁷ Research (LTER) site.

The Florida Coastal Everglades LTER site is one of 26 such NSF LTER sites around the world in ecosystems from forests to tundra⁸（苔原） , coral reefs to barrier islands.

"Seagrasses have the unique ability to continue to store carbon in their roots and soil in coastal seas," said Fourqurean. "We found places where seagrass beds have been storing carbon for thousands of years."

The research was led by Fourqurean in partnership⁹ with scientists at the Spanish High Council for Scientific Investigation¹⁰, the Oceans Institute at the University of Western Australia, Bangor University in the United Kingdom, the University of Southern Denmark, the Hellenic Center for Marine¹¹ Research in Greece, Aarhus University in Denmark and the University of Virginia.

Seagrass meadows, the researchers found, store ninety percent of their carbon in the soil--and continue to build on it for centuries.

In the Mediterranean¹², the geographic¹³ region with the greatest concentration of carbon found in the study, seagrass meadows store carbon in deposits many meters deep.