Measurement of soil dry aggregate size distribution using the laser diffraction method

Abstract Aggregate size distribution of soil is an important parameter to describe soil properties. For many years, the size of soil aggregates has been measured using the dry sieving method. During sieving, particularly less-stable aggregates may have broken down. However, apart from the sieve method, there was no method enabling direct measurement of aggregates on a dry basis. The modification of the measurement system presented in this paper allows such measurements to be conducted using the laser diffraction method. The average coefficient of variation of the proposed method was about 2.6 %.