Studies on Evaluation Method for Clod Size Distribution of Soil Layer after Tillage (Part 1)

Approximation by Rayleigh's Distributoin to Clod Size Distribution

Abstract

In order to judge the result of tillage, we bust establish the test methods for evaluating the change of soil conditions. We unst numerize the state of soil clods or the state of turning over soil layer. But many problems are stacked on clod size analysis.
There are no standard methods, such as sampler sizes, system of openings of sieves and so on. No valuable method how to express the sieved clod size is generally found.
In this report, the following properties were clarified. The clod size distribution can be well approximated with Rayleigh's distribution and by using the two parameters of Rayleigh's distribution, the followings can be obtained easily; the mean clod diameter in weight, its standard deviation and so on. By this method, the parameters were obtained regardless of the series of openings of sieves. So this method can be recommended for valuable clod size analysis.