The Colorado River is a vital resource in the United States and Mexico but is susceptible to detrimental salinity levels with salinity-related damages estimated at $385 million per year. �Over 55% of sediment and salts entering the Colorado River is of natural origin with a significant contribution from accelerated soil erosion on federal rangelands. This suggests a significant potential to reduce dissolved-solids loading to the Colorado River through land and water-management activities on rangelands. In this study, we aim to develop parameter estimation equations that are valid on saline rangeland sites for use in the Rangeland Hydrology and Erosion Model (RHEM). ). Data from rainfall simulation experiments were used to develop these predictive equations. Along with traditional soil erosion measurement data, information on soil salinity and sodicity represented by Electrical Conductivity EC and Sodium Adsorption Ratio (SAR) were included in the parameter estimation equations to improve runoff and erosion modeling in salt-affected conditions. Runoff and soil loss prediction performances were assessed with the Nash-Sutcliff Efficiency (NSE), the coefficient of determination (R2) and the percent bias (PBIAS). These new developments will provide a physically-based modeling scheme to land managers for predicting rainfall-driven soil and salt load to surface waters of the Upper Colorado River Basin.
Oral presentation and poster titles, abstracts, and authors from the Society for Range Management (SRM) Annual Meetings and Tradeshows, from 2013 forward.