Skip to main content
ARS Home » Pacific West Area » Pullman, Washington » Northwest Sustainable Agroecosystems Research » Research » Publications at this Location » Publication #197549
Title: WEPP WITH ENERGY-BASED WINTER ROUTINE FOR SIMULATING WINTER HYDROLOGIC PROCESSES IN THE PACIFIC NORTHWEST, USA

Author
item GREER, R. - NRCS
item LIN, CHUN-HSU - INST OF ENVIRON/RES TAIPE
item SINGH, PRABHAKAR - WASHINGTON STATE UNIV
item DUN, SHUHUI - WASHINGTON STATE UNIV
item WU, JOAN - WASHINGTON STATE UNIV
item McCool, Donald

Submitted to: ASABE Annual International Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 3/17/2006
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: The unique winter climate of the Northwestern Wheat and Range Region (NWRR) of the Pacific Northwest USA produces high erosion throughout the winter season. The unique winter rain and snow season, steep slopes, intermittent freeze and thaw of soils, and improper management practices contribute to the excessive soil loss. During thawing periods, soil strength is reduced and storm events can easily detach and transport the soil. To better understand the winter hydrology and erosion processes in the Pacific Northwest (PNW), a combination of field experimentation and mathematical modeling was implemented. The specific objectives of our study were to evaluate (i)the effect of no-till and conventional tillage on winter hydrologic (including snowmelt, soil frost and runoff) and erosion processes and (ii) the performance of the USDA’s WEPP (Water Erosion Prediction Project) model with modified energy-based winter routines in predicting erosion and hydrologic processes. Surface runoff and sediment were collected for three paired field plots under conventional tillage and no-till, respectively. For two selected plots, soil moisture and temperature were continuously monitored at several depths. Suitability and performance of the modified WEPP model were assessed under PNW winter conditions. Field observations revealed that minimal erosion was generated on the no-till plots, whereas erosion from the conventional tilled plots largely exceeded the tolerable rates recommended by the Natural Resources Conservation Service. The modified WEPP model could reasonably reproduce the winter processes (e.g., snow and thaw depths and runoff).