ARS | Publication request: Current water erosion studies at Pullman, WA, USA

Submitted to: International Soil Conservation Organization Conference Proceedings
Publication Type: Proceedings
Publication Acceptance Date: April 15, 2008
Publication Date: N/A

Interpretive Summary: Movement of water through the soil during natural freezing and thawing in cold regions can have a major effect on infiltration and permeability, and is difficult to measure as well as model. Long-term studies on extensively instrumented experimental plots at the USDA-ARS Palouse Conservation Field Station near Pullman, WA, USA are targeted toward obtaining a better understanding of water movement into and through the soil under freeze/thaw conditions, with the objective of improving winter process modeling. Two treatments, continuous tilled fallow and long-term no-till winter wheat after spring barley, provide a wide contrast in management and in runoff and erosion results as well. Instrumentation includes soil water probes and temperature sensors installed incrementally to a depth of 1 m. Weather data include temperature, precipitation, wind speed and direction, solar radiation, and relative humidity. Runoff and soil loss are measured throughout runoff events. These data are currently being used to validate an energy-budget-based winter process module recently implemented in the USDA-ARS Water Erosion Prediction Project (WEPP) model. Data and results from the first four years of the study are presented, along with results of using the data to test the modified WEPP winter process module.

Technical Abstract: Long-term studies on extensively instrumented experimental plots at the USDA-ARS Palouse Conservation Field Station near Pullman, WA are targeted toward obtaining a better understanding of water movement into and through the soil under freeze/thaw conditions, with the objective of improving winter process modeling. Two treatments, continuous tilled fallow and no-till winter wheat after spring barley, provide a wide contrast in management and in runoff and erosion results as well. Instrumentation includes soil water probes and temperature sensors installed incrementally to a depth of 1 m. Weather data include temperature, precipitation, wind speed and direction, and relative humidity. Runoff and soil loss are measured throughout runoff events. These data are currently being used to validate a new energy-budget-based winter process module recently implemented in the USDA-ARS Water Erosion Prediction Project (WEPP) model. The data can be used in development and validation of other models as well. Data and results from the first four years of the study will be presented, along with results of the new winter process module in WEPP with current and historical data.