Bayesian estimation of erosion parameters. Part II. Application

This is a second article of a two-part study to improve the estimation of erosion parameters using Bayesian methods. Here the general relationships developed in the first article are applied to interrill and rill erodibilities. Prior information is represented by regression equations of the WEPP data set. A normal distribution of interrill erodibility and a log-normal distribution of rill erodibility are assumed. These assumptions are shown to be reasonable. The proposed Bayesian technique is tested using the relatively large data base contained in WEPP and for three soils not included in the regression data base. Overall, the technique works very well resulting in a more reliable and usually smaller spread in the probability density functions. It appears to be a very useful procedure for combining site-specific information with that contained in a national data base.