From year to year, any number of events can alter landscapes in and around North Coast and Cascades Network parks, including landslides, fires, clearcuts, and human development. These landscape changes occur at a wide variety of scales of time, extent, and magnitude, from a small flood that scours a riparian zone to a large fire that burns thousands of acres. Regardless of size and severity, each event can have lasting effects on the rest of the ecosystem, which include changes in hydrologic regimes, nutrient cycling, water quality, distribution of exotics, and quality of wildlife habitat. The Landscape Change monitoring program detects and maps where these landscape changes occur, how severe they are, and how long they last. The goal of this program is to document current rates of landscape change providing a baseline against which human-induced change can be compared in the future.
- Provide knowledge about trends in the size, frequency, or severity of landscape change events for land management and facilities planning.
- Provide a landscape-scale context for interpreting trends documented in other North Coast and Cascades Network monitoring projects.
By documenting landscape change over long periods, North Coast and Cascades Network National Parks can better assess the risks of climate change to natural and cultural resources.
The Great Coastal Gale of 2007
Tracking natural landscape change over long periods of time can help us in predicting the effects of climate change on park natural and cultural resources. Explore this story map to learn how the landscape change caused by several very large storms in 2007 affected the resources at Lewis and Clark National Historical Park, and how mapping the extent of these changes assists park managers in decision-making. Click here, or on the image to the left, to view the story map.
The Landscape Change monitoring program uses satellite imagery, Geographic Information System, and statistical analysis to evaluate landscape changes in and around network parks. The program tracks the size, duration, and intensity of each landscape change. The specific objectives are to:
- Detect and map landscape changes that are larger than 0.8 ha (2 ac) resulting from an avalanche, clearing, development, fire, mass movement, progressive defoliation, riparian flooding, or tree toppling.
- Determine trends in the size, magnitude, location, and spatial distribution of each landscape change category.
Each year, Landsat images undergo analysis using a program called Landsat-based Detection of Trends in Disturbance and Recovery (LandTrendr) to detect new areas that have changed compared to the previous year. Individual patches larger than 0.8 ha (2 acres) and where at least 10 percent of the vegetation has been removed are delineated. Next, the patches are labeled with a change agent, such as fire, mass movement, clearcut, or riparian flooding. To create the label, a statistical model combines information about the patch’s shape, size, and location on the landscape with the information about the event duration and magnitude from the Landsat images. For example, a square-shaped patch outside the park boundary in which a tall forest canopy has been removed and only bare ground remains is likely to be a clearcut. Maps of the change areas are created for each park every three years.
Reports and Publications
Last updated: August 24, 2023