Southern California, one of the most biodiverse regions of the United States, faces unprecedented threats to its natural resources. It is particularly vulnerable to climate change because of the way in which the region’s mountains and coastlines affect the timing and distribution of precipitation. More frequent drought and fire, encroaching urban development, and overuse of recreational resources are taking a toll on the unique chaparral and oak and pine woodlands in the region. Four national forests in southern California provide key ecosystem services (water, recreational opportunities, habitat, etc.) that may be threatened by these stressors. To determine the extent of vulnerability, Forest Service scientists are conducting a biophysical and socioeconomic vulnerability assessment of ecosystem services to landscape-level disturbance in the Los Padres, Angeles, San Bernardino, and Cleveland National Forests.
This project quantifies and economically values the following ecosystem services on the landscape: 1) Water quantity and quality, including watershed capacity to regulate erosion and sedimentation 2) Recreation opportunities 3) Carbon sequestration The project also evaluates the legal obligations and responsibilities of the Forest Service pertaining to air quality, biodiversity, energy and minerals, and cultural, tribal, and spiritual services. An economic valuation will be undertaken to assess the impacts of wildfire smoke on human health.The San Gabriel Mountains (left) in the Angeles National Forest; one of four national forests included in a Forest Service-led biophysical and socioeconomic vulnerability assessment of ecosystem services in southern California. USDA Forest Service photo.