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ARS Home » Pacific West Area » Pullman, Washington » Northwest Sustainable Agroecosystems Research » Research » Publications at this Location » Publication #92794
Title: SUPPORT PRACTICE FACTOR (P)

Author
item Foster, George
item WEESIES, G - NRCS
item Renard, Kenneth
item YODER, D - UNIV. OF TENNESSEE
item McCool, Donald
item PORTER, J - NRCS

Submitted to: Predicting Soil Erosion by Water A Guide to Conservation Planning
Publication Type: Government Publication
Publication Acceptance Date: 1/1/1997
Publication Date: N/A
Citation: N/A

Interpretive Summary: Erosion prediction is used to develop and evaluate crop management systems and is of national and world-wide importance if we are to protect our natural resource base and provide food and fiber for a growing population. This handbook reports major revisions and improvements to the most widely used erosion prediction model world-wide, the Universal Soil Loss Equation. The chapter on support practice factors will improve erosion prediction on the over 400 million acres of cropland in the United States, and ensure better use of federal funds spent on application of conservation practices. The revision is applicable to cropland, rangeland, and forest land and will improve land use and crop management systems planning throughout the world.

Technical Abstract: The Revised Universal Soil Loss Equation (RUSLE) is an erosion model predicting longtime average annual soil loss (A) resulting from raindrop splash and runoff from specific field slopes in specified cropping and management systems and from rangeland. Widespread use has substantiated the RUSLE's usefulness and validity. RUSLE retains the six factors of Agriculture Handbook No. 537 to calculate (A) from a hillslope. Technology for evaluating these factor values has been changed and new data added. The technology has been computerized to assist calculation. Thus soil-loss evaluations can be made for conditions not included in the previous handbook using fundamental information available in three data bases: CITY, which includes monthly precipitation and temperature, front- free period, annual rainfall erosivity (R) and twice monthly distributions of storm erosivity (E); CROP, including below-ground biomass, canopy cover, and canopy height at 15-day intervals as well as information on crop characteristics; and OPERATION, reflecting soil and cover disturbances that are associated with typical farming operations. Chapter 6 covers the support practice factor (P) and changes from previous versions of the USLE that will improve erosion prediction.