Forestry and global warming
Forestry plays a crucial role in the context of global warming, acting as both a source and a sink for carbon. Sustainable forest management is key, as it aims to balance the regeneration and utilization of forest resources while preserving their ecological integrity. This management involves careful consideration of factors such as timber production, wildlife habitats, and non-timber resources, ensuring that the benefits derived from forests do not compromise their health over time. Forests are significant carbon stores, capturing carbon in various forms, from living trees to soil. However, disturbances like forest fires, pests, and deforestation can lead to substantial carbon emissions, exacerbating climate change. As global temperatures rise and precipitation patterns shift, forests may face challenges in adapting to new environmental conditions. The need for sustainable practices is emphasized, as they help maintain forest health and resilience, ultimately contributing to global carbon balance. The future of forestry will likely involve increased demands for sustainable wood production and ecosystem services, highlighting its importance in addressing climate change.
Subject Terms
Forestry and global warming
Definition
Forests are both sources and sinks for carbon. Forest management therefore has the potential to be a means to either increase or decrease forest-based carbon storage. Forestry is a practical science concerned with creating, managing, using, and conserving forests and associated resources in a sustainable manner that meets societal goals. Forest management involves the regeneration, management, utilization, and of forests to meet goals and objectives of society while maintaining the productive potential of the forest. The products, services, and values obtained from a forest include wood, water, wildlife, recreation opportunities, food products, aesthetic beauty, and many others.
A central tenet of forestry is sustainability—ensuring that the products, services, values, and inherent productivity of the resources are sustained over time. An old concept in forestry is sustained yield, meaning that the amount of resources removed from a forest is equal to the amount grown or produced in that forest. This concept has traditionally been most used to define the limits of sustainable timber production: No more timber should be removed from the forest than is grown in any given cycle. Similar concepts apply to the production of wildlife, grasses for forage or livestock, and nontimber such as berries, floral greenery, mushrooms, and so on.
Forest stands in which trees are roughly the same age are typically managed over rotations of twenty to over one hundred years, depending on species, site quality, and specific management objectives. Multiaged stands—which include multiple age classes of trees—are managed over cutting cycles that may range from five to over fifty years. Ideally, stands are maintained at different stages of development, so the forest as a whole may include a variety of stand ages and stand structures.
Many stands are managed to form simple structures that consist of a single tree species planted at consistent spacings and possibly with similar genotypes. Other stands are grown to have many species and multiaged structures. A regulated forest has an arrangement of stand structures that yields a constant production over time. This arrangement represents an ideal that is rarely met, because, over the long time span of forest growth, there are often changes in land ownership patterns, management directives, and regulations that affect how and which lands are managed, as well as disturbances such as fire.
Significance for Climate Change
Forestry also involves the management of fuels and their arrangement in forest stands. Forest fires occur over broad areas every year in both temperate and tropical forests and result in massive carbon emissions. Insects and represent another potential hazard to forests that may increase fuels and fire hazards, lead to large-scale carbon emissions, and reduce the ability of the forest to meet other needs. Forests that are resistant to disturbance present an opportunity to conserve carbon on a large scale. Forests with natural functions and processes, endemic levels of insects and pathogens, and normal levels of are said to be healthy. Regardless of specific objectives for any forest land, maintenance of forest health is a common, overriding objective for managed forests.
Forests store large amounts of carbon in living, above-ground stems, branches, and foliage; below-ground root structures and fine roots; dead, woody objects, such as logs, decomposing foliage, and twigs; and soil. Forest management activities affect these components and therefore affect a site’s carbon balance. A clear-cut harvest will remove all stems but will typically not remove branches, foliage, some stemwood, or any below-ground components. A selection treatment to create a multiaged stand structure would remove a smaller number of trees. Other regeneration methods that remove intermediate amounts of trees produce intermediate results.
In addition to these direct effects on forest carbon, treatments and related soil disturbance may affect the rate of decomposition of plant materials and soil carbon. Disturbances such as fire, wind, or insect or pathogen attack can cause similar effects. Following treatment or disturbance, stands regrow, replacing trees and carbon. A forest managed on a sustainable basis would have a relatively constant level of carbon present, as well as wood fiber and other resources. Permanent removal of forests, or deforestation, generally results in reduced carbon storage. When wood and other forest products are removed and put into long-term use sustainably, however, they represent an additional source of carbon storage that supplements the forests. Likewise, wood used for energy production results in temporary carbon loss in the forest but in a net carbon savings through offsets of nonrenewable fuels.
Forests represent both a source and a sink for atmospheric carbon. Under global warming climate scenarios, forests will experience greater concentrations of atmospheric carbon dioxide (CO2), rising temperatures, and altered precipitation patterns. These changes may result in greater growth rates in some cases. Given the long life span of trees, however, they may have poor evolutionary adaptability to changing climatic conditions in their native ranges. Species can be moved to more suitable climates, but species are adapted to both climate and photoperiod.
Future forests are likely to receive greater pressure to produce wood and other ecosystem services including using wood as energy. D remains another threat to global carbon balance, as forests are replaced with agricultural lands or converted to other uses. Forests are an integral part of the global carbon equation and heavily subject to human influence. Management of forests to offset carbon losses, meet demands for wood and other forest products, cultivate ecosystem services, reduce losses to fire, provide biodiversity, and promote healthy forests all indicate the continued great importance of forestry in the future.
Bibliography
"Climate Change Impacts on Forests." US Environmental Protection Agency, 22 Oct. 2024, www.epa.gov/climateimpacts/climate-change-impacts-forests. Accessed 17 Dec. 2024.
Freer-Smith, P. H., M. S. J. Broadmeadow, and J. M. Lynch, eds. Forestry and Climate Change. Oxfordshire, England: CABI International, 2007.
Kohm, K. A., and J. F. Franklin, eds. Creating a Forestry for the Twenty-first Century. Washington, D.C.: Island Press, 1997.
Puhe, J., and B. Ulrich. Global Climate Change and Human Impacts on Forest Ecosystems. Ecological Studies 13. Berlin, Germany: Springer, 2001.