Taiga

Boreal forests are estimated to store twice as much chemically pure carbon per unit area as tropical forests.

An excerpt from the article 19 facts about Taiga
According to scientists, the North's ecosystem has bound and stored 208 billion tons of chemically pure carbon, including 71 billion tons in boreal forests and 137 billion tons in peatlands. This amount of clean carbon equals the total of all industrial gases emitted globally into the atmosphere in 26 years. Moreover, one hectare of boreal forest sequesters almost twice as much chemical clean carbon as a hectare of forest in the tropics.