New method for quantifying water stability of soil aggregates from air bubbling after immersion

Abstract Existing methods for estimation of water stability of aggregates suffer from intrinsic uncertainties and are not more than semi-quantitative. New method for quantitative measurement of aggregate destruction rate in water was developed basing on monitoring of air bubbling after aggregate immersion by recording a decrease in buoyancy of the aggregate during air evolution. The method allows to estimate destruction mechanism and to calculate kinetic parameters of the destruction process. The rate of the destruction of spherical aggregates made from 2-mm sieved soil material was successfully fitted to a shrinking sphere model. The time of the complete destruction divided by the initial surface of the aggregate was constant for a given soil regardless the aggregate size and it was used as a parameter distinguishing different soils. The proposed method allows for studying rapidly destroyed aggregates for which all available methods generally fail.