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A landscape scale valley confinement algorithm: Delineating unconfined valley bottoms for geomorphic, aquatic, and riparian applications

Informally Refereed

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.
Citations
https://www.fs.usda.gov/research/treesearch/45825