Simple models of the role of forests and wood products in greenhouse gas mitigation

The exchange of carbon, primarily as the greenhouse gas carbon dioxide, between forests and the atmosphere, gives forest managers opportunities to limit greenhouse gas emissions through forest management. Options available to forest managers to reduce greenhouse gas emissions include 1) storing carbon in landscapes, 2) storing carbon in wood products, and 3) providing society with a low-emissions resource (wood products) to substitute for alternative materials associated with larger emissions. To evaluate the trade-off between storing carbon in forests and providing society with wood products, the dynamics of each option must be understood. Here, the above options are explained using simple models analogous to reservoirs and safes. Reservoirs are used to represent dynamic systems, such as forest and wood product carbon stocks, and the irreversible substitution effect, where emissions are avoided through the use of wood, is shown as analogous to placing avoided emissions in a safe.