Location: Great Basin Rangelands Research2009 Annual Report
1a. Objectives (from AD-416)
This research will improve our knowledge-base regarding contributions that different vegetation plant communities play in producing surface runoff and soil erosion rates in rangeland watersheds. We hypotheses that alternative stable vegetative states (i.e., cheatgrass dominated sites) will have different hydrologic responses (i.e., infiltration rates, peak discharge rates, and sediment loads) than historical Wyoming sagebrush plant communities. We further hypotheses that sites that have been revegetated will be intermediate in hydrologic response to the historical and disturbed site conditions.
1b. Approach (from AD-416)
The majority of the state of Nevada is rural and limited hydrologic studies have been carried out to investigate surface water hydrology in remote upland regions of the state. For rainfall, there is a limited network of meteorological stations for which data are available through the National Weather Service. Thus the measurement of surface water contributions in small rangeland catchments with intermittent surface runoff is very limited. We propose to investigate the feasibility of instrumenting existing wildlife guzzlers in Nevada to provide data on precipitation and surface runoff in remote catchments. By using a simple water balance approach with appropriate monitoring equipment for precipitation and water levels in the guzzler storage tanks, the amount of surface runoff generated by a particular natural storm can be determined. The second phase will be to estimate the hydrologic response of the different vegetative states within these catchments with a rainfall simulator (2 m wide x 6 m long) at rates 5, 10, 12.5, 15, 17.5 cm per hour. This will provide the baseline data for the watershed analysis of hydrologic response of specific vegetative states at the hillslope scale. Data from these experiments will be used to validate and improve the Rangeland Hydrology Erosion Model and the Soil Water Assessment Tool and will provide benchmark information for the USDA Conservation Effects Assessment Project. Documents SCA with U of NV-Reno.
3. Progress Report
This project documents research conducted under Specific Cooperative Agreement between ARS and The University of Nevada at Reno. Scientists working on the Conservation Effects Assessment Project have developed a new rangeland hillslope soil erosion model entitled Rangeland Hydrology Erosion Model (RHEM). This model introduces a new paradigm for estimating and reporting soil erosion on rangelands. This new technology will replace the Universal Soil Loss Equation technology that estimates average annual soil loss. The project sponsored a symposium at the annual Society for Range Management Conference on Rangeland Hydrology and Erosion Technology Advancements where ARS presented this new rangeland soil erosion technology to over 250 people who attended this 4 hour symposium. Up to date information, publications, and links to soil erosion and watershed models developed and enhanced by the CEAP project team may be found at http://www.nrcs.usda.gov/TECHNICAL/NRI/ceap/index.html. Additional details for the research can be found in the report for the parent project 5325-11220-006-00D integrated invasive species control, revegetation, and assessment of Great Basin rangelands. In addition, the University PI sends monthly emails describing progress on the project and prepares agenda for quarterly meetings held to discuss the project. The ADODR has quarterly meetings with University partners to assess status of the project and make corrections to the research approach as required to meet the goals of the project.