Spatial heterogeneity as a component of river geomorphic complexity

One component of geomorphic complexity results from spatial heterogeneity in river corridors. The characteristics of this form of complexity have important implications for habitat and biodiversity, attenuation of downstream fluxes, resistance and resilience of river ecosystems, river processes, ability to characterize patterns and changes through time, and river management and restoration. Numerous measures of complexity have been applied to heterogeneity from spatial scales of bed grain size distribution to entire river networks. Studies explicitly incorporating geomorphic complexity have increased substantially since 2000, but there is no single, widely used metric of complexity. Despite increasingly explicit scientific appreciation of the importance of complexity in river corridors, public attitudes toward rivers continue to emphasize an attractive appearance, which commonly equates to a physically simple and homogeneous river corridor.