Impact of Kinetic Energy of Failing Drops upon Soil lnfiltrability.

A Laboratory experiment was carried out on long column of clay loam soil exposed to sprinkler (rain) simulator to study the effect of kinetic energy of falling drops (K.E.) on soil infiltrability which was represented by time of surface ponding (ts) and water penetration depth (ls). A range of raindrop kinetic energies was created by changing failing distance (5-200 cm) and sprinkler intensity (3.3-6.5 cm h-1). A concept of threshold kinetic energy (K.Eo). which was defined as a minimum energy needed to initiate surface ponding, was introduced into a proposed model to estimate ts and Ls. A simple model was also proposed to estimate K.Eo. The study showed that K.Eo was linearly related to sprinkler intensity (R). and both ts and Ls were decreased exponentially as K.E was increased. The results supported the model which was of the form ts = to s - Ct (K.E - KEo)n, where tos is time for surface ponding produced by KEo. Ct is a parameter depending on R, and n is an exponent equal to 0.65 which is an entity for the soil