Approach
Species are vulnerable to stressors at different stages of their life cycle, such that even-aged stands are often more vulnerable to disturbances such as insect pests and disease. Likewise, greater compositional diversity may reduce vulnerability to disturbances. As one or more species are at risk for a given stressor, greater diversity reduces the likelihood that the entire systems will decline. Even as greater species and structural diversity confer reduced vulnerability to carbon losses from disturbance, particularly under a changing climate, these characteristics can also increase carbon density in forest ecosystems. Higher rates of carbon storage and annual carbon sequestration can result from resource-use efficiencies from increased diversity of tree species, while increased carbon stocks can be supported with a greater diversity of age classes and more vertical and horizontal structural complexity. Results from both modeling and experimental studies suggest that over longer time scales (e.g. 50-100 years) silvicultural practices that promote uneven-aged management in forests promote greater carbon stocks in forests. Carbon stocks in forests managed for increased structural and species diversity may increase over long temporal scales despite short-term reductions in carbon.
Tactics
- Forest management practices that emulate aspects of disturbance, such as variable density treatments.
- Smaller, more frequent management interventions to encourage the development of multiple age cohorts or greater species diversity.
- Silvicultural treatments that encourage diverse regeneration of native species, such as larger patch cuts.
- Using salvage methods that create desired residual stand structures following disturbance.
Strategy
Strategy Text
Climate change is projected to increase the potential for severe disturbance events that reduce forest ecosystems carbon stocks, while additionally affecting the growth and regeneration of extant species. Many forest management decisions aim to limit the negative impacts of disturbances while enhancing the growth of residual trees and the regeneration of desired species that represent the current and future capacity of the ecosystem to sequester carbon. Often these management actions aim to enhance existing forest conditions, such as species composition and stand structural diversity that are key to the desired services provided by the forest. Slight adjustments in forest conditions can improve the retention of carbon within various forest carbon pools or enhance the rate of recovery following a disturbance event without dramatically altering the character of forest ecosystems.
Todd A Ontl, Maria K Janowiak, Christopher W Swanston, Jad Daley, Stephen Handler, Meredith Cornett, Steve Hagenbuch, Cathy Handrick, Liza Mccarthy, Nancy Patch, Forest Management for Carbon Sequestration and Climate Adaptation, Journal of Forestry, Volume 118, Issue 1, January 2020, Pages 86–101, https://doi.org/10.1093/jofore/fvz062