Project Number: 5325-11220-005-08
Project Type: Specific Cooperative Agreement

Start Date: Sep 30, 2008
End Date: Sep 30, 2010

Objective:
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.

Approach:
During the last 2 decades the rangeland profession has been striving to develop new theories and concepts of how ecological processes function on rangelands and how to quantify the health of rangelands. State-and-transition models to describe vegetation dynamics on rangelands are now being developed to address the multiple stable states that can exist within an ecological site. In conjunction with describing these states, the natural and anthropogenic processes required to facilitate a plant community moving from one state to another state are being described. However, there is minimal quantitative information on the biotic attributes (i.e., canopy cover, ground cover, plant height, plant density and gap frequency) and hydrologic function and response within each of these states and no quantitative information on the hydrologic response after the state has been altered. Monitoring sites will be established across the interface of sagebrush steppe plant communities in varies stable states to document ecological process and quantify change in plant community structure and function. 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.