MODELING SURFACE-ROUGHNESS BY A BOOLEAN APPROACH

A model for simulating surface roughness of an agricultural bare soil is described. The model used a random Boolean function. The primary fu nction was a sphere with radius r lying on a plane. The intensity func tion, a(r), of the distribution of the sphere radius was described by a(r) = alpha r(beta)exp(lambda r). Microtopography data were collected during two sets of field experiments. The distribution of experimenta l heights was used for fitting the three parameters, (alpha, beta, lam bda) of the intensity function a(r) with a pseudo-likelihood method. C omparisons between experimental and simulated soil surfaces indicated that the simulated roughness was not unrealistic. However, they also s howed that the model is currently limited by the primary function and the intensity function that were chosen.