Britannica Sources used in this answer

How do forests store carbon and influence the carbon cycle?

Created from Britannica articles using AI. AI can make mistakes, so verify using Britannica articles.

Tall giant sequoia trees with reddish bark and thick trunks rise closely together in a dense forest at Sequoia National Park, California. — Tree A stand of giant sequoia trees (*Sequoiadendron giganteum*) in Sequoia National Park, California.

Forests play a vital role in the global carbon cycle by acting as carbon sinks—reservoirs that retain carbon and prevent it from entering the atmosphere as carbon dioxide.1

How Forests Store Carbon

Forests sequester carbon primarily through photosynthesis, a process where plants remove carbon dioxide from the atmosphere to build their tissues. This carbon is stored in two main ways:21
* Aboveground Biomass: Carbon is held within the physical structure of trees, shrubs, and other vegetation.1
* Soil: Carbon that is not used directly by plants becomes litter and is eventually incorporated into soil humus.2

Influence on the Carbon Cycle

Forests regulate the global carbon budget by balancing uptake and release. While they sequester carbon, they can also become carbon sources if that stored carbon is released back into the atmosphere through decomposition or combustion (such as forest fires).21

Human activities, particularly deforestation, disrupt this cycle by removing the vegetation that captures carbon and causing the release of stored carbon as trees decay or burn. Conversely, reforestation and the preservation of existing forests are essential strategies for mitigating global warming by maintaining these critical terrestrial sinks.31