Author
Weltz, Mark | |
NOUWAKPO, SAYJRO - University Of Nevada | |
Nesbit, Jason | |
MCGWIRE, KENNETH - Desert Research Institute |
Submitted to: World Conference Soil and Water Conservation Under Global Change (CONSOWA)
Publication Type: Proceedings Publication Acceptance Date: 5/25/2017 Publication Date: 6/12/2017 Citation: Weltz, M.A., Nouwakpo, S.K., Nesbit, J.E., Mcgwire, K.E. 2017. New Tools to Estimate Runoff, Soil Erosion, and Sustainability of Rangeland Plant Communities. World Conference Soil and Water Conservation Under Global Change (CONSOWA). 144. Interpretive Summary: Rangelands are the largest land cover type in the world. Degradation from mismanagement, desertification, and drought impact more than 50% of rangelands across the globe. The USDA Agricultural Research Service has been evaluating sustainability of rangeland for over 40-years by using rangeland rainfall simulation experiments (>100 plant communities) across the U.S.A. The data from these experiments has been assembled into a relational database (Agricultural Runoff Erosion, and Salinity - ARES). This database is being used to understand impacts of land management practices on hydrologic processes and rangeland sustainability. Results from analyzing the data in central Colorado, U.S.A. indicate that long-term heavy grazing does increase runoff rates and volumes. The database was also used to evaluate salt transport and soil erosion processes in central Utah, U.S.A. with the Rangeland Hydrology and Erosion Model (RHEM). RHEM did an excellent job in predicting runoff at the Utah, U.S.A. sites over all rainfall intensities applied. The model did a good job of estimating sediment yield for saline and sodic sites. There was a very strong correlation between observed sediment yield and observed total dissolved solids. The ARES database and REHEM decision support tool can be used to quantify sustainability of rangelands in relation to land management practices impacts on rangeland hydrologic and soil erosion processes and salt transport processes that impair water quality. Technical Abstract: Rangelands are the largest land cover type in the world. Degradation from mismanagement, desertification, and drought impact more than 50% of rangelands across the globe. The USDA Agricultural Research Service has been evaluating sustainability of rangeland for over 40-years by conducted rangeland rainfall simulation experiments (>100 plant communities) across the U.S.A. The data from these experiments has been assembled into a relational database (Agricultural Runoff Erosion, and Salinity - ARES). This database is being used to understand impacts of land management practices on hydrologic processes and rangeland sustainability. Results from analyzing the data in central Colorado, U.S.A. indicate that long-term heavy grazing does increase runoff rates and volumes. The database was also used to evaluate salt transport and soil erosion processes in central Utah, U.S.A. with the Rangeland Hydrology and Erosion Model (RHEM). RHEM did an excellent job in predicting runoff at the Utah, U.S.A. sites (R2 0.90) over all rainfall intensities applied. The model did a good job of estimating sediment yield (R2 0.58) for saline and sodic sites. There was a very strong correlation (R2 0.84) between observed sediment yield and observed total dissolved solids. The ARES database and REHEM decision support tool can be used to quantify sustainability of rangelands in relation to land management practices impacts on rangeland hydrologic and soil erosion processes and water quality. |