Riparian Land Cover Classification to Guide Conservation and Restoration of the Lower White River, Utah; William Macfarlane

Increasing human demands for water threaten rivers and their associated riparian and aquatic ecosystems across the western US. Channel narrowing, an ecological response to reduced streamflow, which is enhanced by nonnative plant invasions can greatly reduce channel complexity and aquatic habitat for endangered native fishes. Such degradation poses significant resource concerns and has necessitated the development of a new conservation and restoration plan on the lower White River, Utah to prioritize reaches and sites for a variety of restoration actions. A riverscape-wide land cover classification was developed in order to properly inform such restoration actions. This project resulted in a high resolution (0.6 m), highly accurate land cover map (77.6% accuracy) of 77 km of a section of the lower White River using a combination of field data, freely available imagery, Object-Based Image Analysis techniques and overflight imagery. The resulting land cover classification was used to guide large-scale restoration prioritization as well as nonnative vegetation eradication to reduce further channel narrowing and promotion of healthy cottonwood stands at specific geomorphic features for the formation and maintenance of complex instream habitats formed from wood jams. The cost effective high-resolution riparian land cover classification and conservation/restoration framework can be applied to other riverscapes in the western US.