How can plot-scale measurements of the hydrologic processes that link hillslopes to riparian areas be scaled up to whole catchments? How can reach-scale measurements of groundwater-surface water mixing in riparian and hyporheic zones be scaled up to entire stream networks? How can we transfer our small-catchment scale understanding to larger portions of the landscape or other catchments? What is the nature of hydrologic process scaling? These questions highlight our current inability to scale-up understanding of hydrological processes studied at the plot or reach scale to larger catchments. Answering them requires integrated, multi-scale approaches that combine landscape-level topographic analysis, process-based field investigations, and catchment-scale integration to identify the factors controlling the hydrologic connectivity between source areas generating runoff and the flow paths that link source areas to streams. This research will combine novel landscape and topographic analysis techniques with plot and reach-scale field research to provide context for field investigations, to develop a method for scaling process understanding to the catchment scale, and ultimately to transfer this understanding to other catchments for comparison and catchment classification. Three primary methods will be used: (1) landscape analysis to elucidate catchment scale patterns and organization and as a method to scale-up process study results to the landscape scale, (2) hillslope-riparian plot scale studies to determine first-order controls on connections and disconnections among dominant landscape units, and (3) reach scale process studies on stream-hyporheic zone dynamics to determine landscape controls on exchange and in-stream transport. Landscape analysis will then be used to link internal catchment dynamics to catchment outlet observations. Comprehensive uncertainty analysis of field tracers and landscape data will be incorporated into empirical and landscape analysis modeling. We will compare results of these empirical approaches to theoretical hydrologic and geomorphologic scaling relationships. The intellectual merit of this research will be manifested in the development and application of a method for linking process scale studies to the catchment and landscape scales. The broader impacts include graduate and undergraduate student involvement from study design through data collection, analysis, and presentation. Teacher training and linkages between research and K-12 education and the general public will be made through collaboration with the Big Sky Institute (BSI) for Science and Natural History and through the BSI Society and Science Graduate Fellows Program. In addition, this research will result in widely available landscape analysis software and a methodology for linking field measurements to the landscape scale. This will provide critical site context to inform stream and watershed restoration projects undertaken by federal and state land management and consulting agencies throughout the intermountain west and beyond.
