Mangroves are a massive storehouse of carbon. The mangroves of Indonesia, with its vast expanse of islands and coastlines, cover an area of around 3 million hectares. These tangled trees and the swampy soil they grow in store approximately 3.14 billion tons of carbon, hence they play an important role in climate change mitigation. Indonesia is home to about 1/3rd of the global storage of mangroves, CIFOR scientist Daniel Murdiyarso says. In North Sumatra, scientists measured the amount of carbon in both protected and degraded mangrove forests lining the province.