An Infiltration-Runoff Model for Cultivated Soils

ABSTRACT A model was developed for predicting transient infil-tration into, and runoff from, freshly cultivated and tilled agricultural soils. The proposed model represents the various steps in the generation of surface runoff and was tested by comparing observed and predicted runoff from 13 plots on a Barnes loam soil. The effects of three different tillage treatments were examined; unplowed, plowed and plowed and disked. Using only measured parameters as model inputs produced fair results. However, good to excellent results were achieved follow-ing limited fitting of the three surface sealing parameters. Observed runoff was highly variable, even from plots subjected to the same tillage treatment. This made simulation difficult.