What are forest carbon sinks and sources?
Forests are composed of many stands (areas dominated by trees of similar characteristics and age). A stand is considered a carbon sink when its uptake of carbon dioxide from the atmosphere through photosynthesis exceeds its release of carbon dioxide through processes such as decomposition and burning. It is considered a carbon source when carbon release is greater than carbon uptake. The carbon balance of a forest is the sum of the contributions of its individual stands. A forest can be a carbon sink even if some individual stands are carbon sources, and vice versa. Whether a forest stand is a sink or source at a particular time depends on natural processes as well as management. The rate of carbon uptake due to tree growth is fastest when the trees are young and it slows as the trees become old. Very young stands growing after fire or harvesting are carbon sources because the carbon removal by regrowing trees has yet to catch up with emissions from the decomposition of dead organic ma
