Submitted to: Society for Range Management Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 2/17/2001
Publication Date: N/A
Technical Abstract: Due to the great diversity and complex interactions of vegetation, soils, and climate on rangelands, process-based models designed to evaluate rangeland hydrology and erosion must include sophisticated plant and animal components that simulate changes in vegetation and soil conditions over space and through time. To provide the framework for future model enhancement and investigation of the impacts of management on rangeland ecosystems, several upgrades were made to the SPUR model. First, an infiltration-based hydrology submodel similar to that used in WEPP was dynamically linked to the SPUR2.4 rangeland ecosystem model. The USLE-based erosion component in SPUR was enhanced by incorporating the RUSLE model and dynamically linking the cover factor to estimated changes in soil and vegetation parameters. Further improvements to SPUR's erosion prediction capabilities were accomplished by incorporating WEPP overland flow and erosion algorithms. Initial testing has shown improved sensitivity of runoff and erosion predictions to variations in vegetation parameters. The improved model did a better job of predicting individual thunderstorm runoff events, and estimated 15-year runoff within 12% compared to SPUR2.4. Additional research is needed to develop better, community-based, estimation equations for effective hydraulic conductivity which will further strengthen the vegetation-hydrology linkage within the model.