Abstract
Valley confinement is an important landscape characteristic linked to aquatic habitat, riparian diversity, and geomorphic processes. This report describes a GIS program called the Valley Confinement Algorithm (VCA), which identifies unconfined valleys in montane landscapes. The algorithm uses nationally available digital elevation models (DEMs) at 10-30 m resolution to generate results at subbasin scales (8 digit hydrologic unit). User-defined parameters allow results to be tailored to specific applications and landscapes. Field data were sampled to verify geomorphic characteristics of valley types identified by the program, and a detailed accuracy assessment was conducted to quantify the reliability of the algorithm output.
Keywords
valley confinement,
valley bottom,
stream channel morphology,
fish habitat,
riparian habitat
Citation
Nagel, David E.; Buffington, John M.; Parkes, Sharon L.; Wenger, Seth; Goode, Jaime R. 2014. A landscape scale valley confinement algorithm: Delineating unconfined valley bottoms for geomorphic, aquatic, and riparian applications. Gen. Tech. Rep. RMRS-GTR- 321. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 42 p.