Project Number: 5342-12660-004-02
Project Type: Specific Cooperative Agreement

Start Date: Sep 03, 2003
End Date: Sep 02, 2008

Objective:
Develop a photogrammetric technique to generate high-resolution Digital Elevation Models (DEMs) for watershed applications. Evaluate existing soil erosion models for applicability and accuracy on rangelands.

Approach:
Identify the most adequate resolution of DEMs for process-based soil erosion models, and critically investigate the differences and benefits of using publicly available versus using self generated DEMs for small watershed assessment. Watersheds between 0.5 - 7.5 ha on the Walnut Gulch Experimental Watershed will be used for the analysis. This work involves four distinct operational steps for completion: 1) collection and assessment of existing erosion data, 2) model sensitivity analyses, 3) assessment of model accuracy for predicting the measured erosion, and 4) assessment of potential for practical and useful application of the models on rangelands across the U.S. Existing data from small watersheds, natural runoff plots, and rainfall simulator plots will be organized in a database for model evaluation purposes. Four models will be tested (RUSLE, WEPP, KINEROS2, and HEM). Relative accuracy of the models will be compared and documented, with results reported relative to those expected in the presence of data uncertainty. Documents SCA with U. of AZ. Formerly 5342-12660-003-02S; July 2007.