Revealing the diversity of hydro-geomorphic settings in a Dry Summer Subtropical region with DEM-based modeling

Abstract:

Channel geomorphic settings- characterized by variables such as channel slope, morphology, bankfull width, sediment composition, and valley confinement - play a well-established role in the resulting availability and quality of riparian and aquatic habitat provided by a particular flow regime. However, few attempts have been made to incorporate these variables into predictive models of reach-scale geomorphic setting, presumably because sufficient field measurements over appropriate geographic distributions are not readily available. Coupling terrain analysis with an existing hydrologic classification system provides an opportunity to extend the range of such geomorphic predictive models across spatially-explicit hydrologic classes via a hydrologically stratified sampling campaign to reduce field data requirements. Furthermore, terrain indices can serve as proxies for field measurements, providing first-order predictions of reach-scale geomorphic setting and associated aquatic and riparian habitat to extend the range of the model. This study integrates terrain analysis and classification techniques for the development of a reach-scale hydro-geomorphic classification of a Dry Summer Subtropical region with steep environmental gradients.