Size distribution of aggregates

Abstract

The size distribution of soil aggregates is important because the size of the aggregates determines their susceptibility to movement by wind and water, and because their size is important in determining the dimensions of the pore space in cultivated soils. Mechanical disruption during the course of preparing and sieving the sample is used to break the soil mass into “aggregates” in this procedure. The wetting process usually causes considerable disruption of dry aggregates. The size of the aggregates after this disruption is apparently an important soil parameter. Several methods have been devised to obtain a quantitative measurement of the size distribution of these aggregates. A study concerning the reproducibility of aggregate-size distribution values was reported by the Soil Science Society of America Committee on Physical Analysis. Aggregate-size distribution often is measured to gain information on the size of the aggregates as they exist in the mass of soil.