For some people forests are measured in board-feet of lumber. For others, they are a source of spiritual renewal. But scientists are finding that protecting ancient trees could also be an important new strategy in the fight against global warming.
In the carbon cycle, it's not just the individual tree -- the entire forest plays a role. Leaves take in carbon dioxide, converting it to sugar, which is carbon-based. Some of the sugar is used immediately for energy, converted back to CO2, and released into the atmosphere. The rest is stored in living wood or dead matter, such as fallen leaves and branches. Old-growth forests, in particular, store vast amounts of carbon while continuing to absorb CO2.
The illustration below, by Mieke Roth, is available as a full-size print-quality PDF file here.
Want to do your part? Plant some trees! If you invest in planting new trees, realize that it takes about 20 years for newly forested clear-cuts to start sequestering more carbon than they release. Choose projects that won't cut down the trees as soon as they mature or, even better, that allow trees to see their centennial. Another option: put your money towards saving forests that would otherwise be cut down. Check out World Land Trust, at www.carbonbalanced.org, which is working to conserve forests in Latin America.