The soil aggregates stability index (ASI) and its extreme values

A method for determining maximum–minimum values of the soil aggregates stability index (ASI) is presented. This allows for the calculation of the range of variations of the soil aggregates stability index for destructive changes of soil aggregation and for assuming criterion of the soil aggregation stability evaluation. The data used for the calculations are distributions of soil aggregate frequencies before and after destruction. On the base of the ASI, determined for the tested soil and the range of its possible variations, other indices that characterise the relative nature of aggregate variations have been defined. The presented methodology for the analysis of the soil aggregation stability index has been illustrated for three soils and various methods of water stability determination.