Carbon dioxide (CO2) is the most important anthropogenic greenhouse gas. As forests grow, they absorb CO2 from the atmosphere, in a process called sequestration, while deforestation and forest degradation release it back into the atmosphere. Therefore, the amount of carbon stored in forests is of great scientific, economic, and political interest.
The effects of deforestation are often dramatic. Forest carbon stores can drop from 300 tons per hectare to 20 tons per hectare, says Alessandro Baccini, an assistant scientist at the Woods Hole Research Center. Deforestation in the tropics alone is equal to all of the transportation sources of carbon dioxide globally combined, according to Greg Asner, a staff scientist in the Department of Global Ecology at the Carnegie Institution for Science. Conversely, “if forests are managed productively and not converted to other uses, if the wood is utilized in long term products and for energy in a substitution benefit, one can use forests to take some carbon out of the atmosphere,” says Jeremy Fried, Research Forester at the U.S. Forest Service Pacific Northwest Research Station in Portland, Oregon.