Location: Southwest Watershed Research2009 Annual Report
1a. Objectives (from AD-416)
Objective 1. Provide data bases, knowledge, and information of rangeland erosion at a range of spatial scales for the development, validation, and implementation of erosion decision tools. Objective 2. Develop decision tools including a rangeland specific hydrology and erosion model for the planning and evaluation of sustainable rangeland management.
1b. Approach (from AD-416)
This project addresses the lack of rangeland specific decision tools to quantify the climatic and management effects on the sustainability of rangelands as affected by runoff and erosion. In particular, the Natural Resources Conservation Service (NRCS) and other action agencies have requested a hydrologic and erosion model to contribute to the ecological site description and National Resource Inventory data bases, to assess the efficacy of conservation practices for the Conservation Security Program, and to provide estimates of runoff and erosion for rangeland monitoring and ranch planning. To address this, two objectives were identified: Objective 1. Provide data bases, knowledge, and information on rangeland erosion at a range of spatial scales for the development, validation, and implementation of erosion decision tools and Objective 2. Develop decision tools including a rangeland specific hydrology and erosion model for the planning and evaluation of sustainable rangeland management. Objective 1 consists of three elements on Erosion Processes, one on Conservation Structures, and one on Remote Sensing. The Erosion Processes elements addresses the quantification of the rates and amounts of erosion, sources and sinks of sediment, and biotic and aboitic influences on sediment yield at scales ranging from plot to small watershed. The resulting data and knowledge will be used to validate hydrologic and erosion relationships and for parameter estimation equations for the erosion model. The Conservation Structures element addresses delivering design criteria for local ranchers and provide the erosion model with data on conservation practices. The Remote Sensing element addresses providing parameter estimation for large scale applications of the erosion model and rangeland health assessments. Objective 2 consists of one element on an Erosion Model and one element on an Economic Decision Support System (EDSS). The Erosion Model will be developed for a wide range of erosion related applications, ranging from parameterizing the NRCS ecological site descriptions to ranch planning. The EDSS will be used to calculate the cost benefit ratios of upland conservation management. Formerly 5342-66000-004-00D & 5342-12660-003-00D (4/07).
3. Progress Report
Significant progress was made in the implementation of the newly developed Rangeland Hydrology and Erosion Model (RHEM). A beta version web-based user interface was made accessible on the internet for testing. The interface uses simple inputs including a geographic location, soil type, slope type, and vegetation type and ground cover to parameterize the model. The output includes amounts of runoff and erosion presented as event return periods and up to 5 different management scenarios can be compared with each other. Data from the National Resource Inventory (NRI) in Arizona are being used to parameterize RHEM in order to test if the model reproduces expected trends of runoff and erosion from the NRI sites. Sites in central Arizona (MLRA 38) were selected for rainfall simulator experiments collaboration with NRCS, USFS, the University of Arizona, and private ranchers. In addition, rainfall simulator experiments using the experimental protocol developed by the MU were conducted in central Nevada in collaboration with ARS-Reno, Nevada NRCS, and the owners of the Smith Creek Ranch. Work on a CSREES funded CEAP related project with the MU, University of Arizona, Tucson and University of Wyoming, Laramie included development and parameterization of RHEM and WEPP/KINEROS in Tucson and GIS data base development, vegetation characterization and watershed instrumentation, and AGWA calibration and validation in Wyoming. A new CEAP related project, Evaluation of Soil and Water Conservation Practices on Southwestern Rangelands, with Co-PI’s including scientists from the MU and the University of Arizona was funded by CSREES. The MU has made significant contributions to technology transfer in the form of WEB based natural resource tools including WEPPCAT (effects of climate change on erosion rates) and Facilitator (a multi-objective decision support system) for use by the scientific community, educators, land-use agencies, and policy makers. International activities included continuing collaboration with INIFAP in Mexico on the application of decision support systems in natural resource management and a three month visit to Australia to collaborate with CSIRO in erosion measurement and modeling. The MU sponsored and hosted a program for local teachers in the ARS/Texas A&M program for training future scientists. Using hands-on, inquiry-based activities and seminars from ARS scientists, the project helps introduce actual USDA research into local schools and communities as it helps to inspire the next generation of research scientists. A scientist participated in the 2009 Natural Resources Conservation Workshop for Arizona Youth. A NASA Space Grant Student completed a research project mentored by a scientist and presented the results at the Space Grant Symposium at Arizona State University in May. One PhD and two Master's students at the University of Arizona completed their degrees on research mentored by scientists from the MU.
1. Web-based Rangeland Hydrology and Erosion Model. There are no readily available tools for predicting the effects of climate and management on the amounts of runoff and erosion from U.S. rangelands. To meet this need, a web-based user interface has been implemented by ARS scientists in Tuscan, AZ as a beta version for the newly developed model, Rangeland Hydrology and Erosion Model (RHEM). The interface uses four categories of input including a geographic location, soil type, slope characteristics, and vegetation type and amount of cover to parameterize the model. The resulting output is presented as amounts of runoff and erosion for different return periods and is structured so that different management scenarios can be easily compared. The model will be used by National Resources Conservation Services (NRCS) and land use agencies in assessing the impact of erosion on the sustainability of U.S. rangelands.
2. Ground Based Ultra High Resolution Imagery as a Tool for Managiing Rangeland. Documenting change in vegetation using imagery has been a trade-off between the area covered by the image and image resolution. ARS scientists in Tuscan, AZ used a new robotic camera mount integrated with off-the shelf digital cameras to produce a ground based system for producing very-high-resolution panoramic photographs. This project was initiated to integrate very-high-resolution panoramic images with conventional rangeland monitoring methods addressing three resource management categories: riparian areas, wildlife, and invasive species. It provides another low cost and easy to use tool to assess the sustainability of U.S. rangelands.
3. Low-tech Erosion Control Structure Design. The impacts of low cost erosion control structures on onsite soil moisture have not been well studied. A field experiment was completed by ARS scientists in Tuscan, AZ to quantify the impacts of low-tech erosion control structures on soil moisture and sediment retention. Two types of structures were evaluated in comparison with untreated control sections and results indicated that soil moisture is increased by increasing the time runoff is retained onsite. These results are important for quantifying impacts that heretofore have been anecdotally described and may impact the viability of revegetation efforts on degraded rangelands.
Sanchez-Cohen, I., Moreno, J., Spring, U., Heilman, P., Barrios, J., Padilla, G., Valle, M. 2008. Integrated water management research in Mexico: Opportunity for North American collaboration. Journal of Soil and Water Conservation. 63(6): 212A-213A.