Land
Threats to forested land extend from site-specific concerns to threats across landscapes. From 1953 to 1997, most States (26) had a loss in forest area, according to periodic surveys by the USDA Forest Service (e.g. Smith and others 2004). Nine States had net losses of at least 1 million acres each, ranging up to 6.3 million acres. Five categories of significant changes affecting forest area are afforestation, deforestation, forest fragmentation, forest parcelization, and increased numbers of structures, such as houses, on forest land. Conversions of forestland are also proving to be a significant environmental threat. The wildland loss section quantifies these threats to land.
Even lands that remain in forest are threatened. Wildfire and various management activites can adversely affect soil quality and function. Growing evidence from around the globe indicates that anthropogenic factors including pollution-induced acidification, associated aluminum mobility and nitrogen saturation are disrupting natural nutrient cycles and depleting base cations such as calcium from forest ecosystems. The soil quality section explores the threats to this fundamental feature of healthy forests.
To further review landscape management, consider reading the following Environmental Threats Case Studies:
- Wildland Loss : Forestland conversion leads to ecological effects, (e.g., changes in water quality and wildlife habitat) and socio-economic effects; (e.g., expanding urban-forest interface, reduced long-term timber production possibilities and loss of open space).
- Soil Quality : Explore effects of management and calcium depletion on soil quality.
Encyclopedia ID: p3264
