Figure 3: Examples of varying
landscape subdivision (A and B; Deer Creek, OR), channel edge density (B
and C; North Fork Teanaway River, WA), and class level subdivision of
wood (D and E; Snoqualmie River, WA). Multiple metrics show differences
in spatial configuration between contrasting reaches, all with slightly
differing utility and interpretation.
Landscape level spatial configuration metrics (i.e., those computed across multiple geomorphic unit classes) can be a proxy for characteristics that can be difficult to directly measure. For instance, if lacking quantitative bathymetric data, one could use aerial imagery to map the channel using a geomorphic unit schema defined by units with varying relative elevations (e.g., pools, chutes, riffles, and bars, in order of increasing relative elevation). The subdivision or edge density of those units could indicate variability in channel bed elevation and resulting hydraulic roughness.