2009 Annual Report 1a.Objectives (from AD-416) 1. Define end-user requirements for the GIS-based RUSLE2 interface and establish evaluation criteria for the final product. 2. Establish clear objectives and guidelines for use and development of the tool based on input from key agency partners. 3. Identify and evaluate existing methodologies for using high-resolution DEMs to calculate slope length and steepness, as well as determine the most appropriate aggregation of soil loss calculations across a field landscape. 4. Develop a working prototype of a GIS-based RUSLE2 template. 5. Optimize the current RUSLE2 application to handle multiple calculations. 6. Provide demonstrations for GIS-based RUSLE2 template to SWCDs statewide. 7. Provide training and support for statewide use of the GIS-based RUSLE2 template. 1b.Approach (from AD-416) Develop a summary report of end-user requirements and agency objectives based on stakeholder meetings and interviews. Prepare a list of final evaluation criteria for the GIS-based RUSLE2 template. Prepare a report on most appropriate methodology for using DEMs to interact with RUSLE2 and most appropriate application of RUSLE2 soil loss calculation across a field landscape. Document functional requirements for a GIS-based tool for statewide application. Evaluate slope length and steepness algorithms for applying LiDAR-derived DEMs to RUSLE2 model. Prepare a beta version of GIS-based RUSLE2 for stakeholder evaluation and obtain feedback on the proposed tool. Proivde trainings for beta users on operation of GIS-based RUSLE2 template and and develop a written survey tool for stakeholder evaluation as a precursor to a summary report of stakeholder evaluation results. Prepare an enhanced GIS-based RUSLE2 template based on end-user experiences and requirements. 3.Progress Report The project with the Iowa Department of Agriculture and Land Stewardship and the Agricultural Research Service (ARS) compliments the research project 3625-13000-009-00D. This project is focused on the development of a Geographic Information System (GIS)-based platform for RUSLE2 (Revised Universal Soil Loss Equation, version 2). Estimations of soil erosion through the RUSLE2 model are required for conservation planning; however, there is no geographic platform that can combine the current topographic and soils information into a useable process for easier use of the RUSLE2 model. This project was undertaken to identify and evaluate existing methodologies for using high-resolution digital elevation maps (DEM's) to calculate slope length and steepness, as well as determine the most appropriate aggregation of soil loss calculations across a field landscape. Progress has been made in the integration of the DEM's as part of a GIS platform and an evaluation of landscapes for slope length and slope that can be derived from the DEM's. The initial coding of the model has been completed and efforts are underway to evaluate how the model can be made user-friendly so that the model can be widely used by different individuals. Project progress has occured through quarterly reports.