Challenges to managing forests for carbon sequestration, bioenergy production, and natural adaptation (Invited)

Managing forests for increasing carbon sequestration and bioenergy product is often cited as a way to mitigate greenhouse gas emissions, although the consequences to ecosystems are often unclear or overlooked. Forest carbon sequestration could be maintained or increased by avoided deforestation and forest degradation, afforestation and reforestation. There is much interest in bioenergy production by thinning existing forests and land-use conversion to plantations. Regional analysis in the western U.S. shows that thinning to prevent fire emissions or to provide stock for bioenergy from existing forests results in a decrease in forest carbon stocks and net biome production (NBP) and increased emissions. A separate DGVM model analysis predicts declines in water availability to some forests, leading to large increases in forest area burned and severity by the end of the 21st century with climate change, and suggests those forests could be thinned to reduce competition for water and minimize impacts. Land-use conversion and broad-scale repeated thinning ignores the potential consequences to habitat, species migration (natural adaptation), and other ecosystem services. To facilitate adaptation of forests to climate change, there is a need sustaining genetic and species diversity through forest preservation and landscape connectivity for migration of plant and animal species. Improved high-resolution regional analysis is needed to include these effects on potential future distribution of species in addition to carbon, water and nutrient cycling in the face of climate change.