Clay Activity Index as an Indicator of Soil Erodibility

Abstract

Activity index (AI) value characterizes the relationship between the plasticity indexand clay content. In this study, AI value was investigated to determine whether it mightbe used as an indicator of soil structural stability or not. The AI values of 75 soilsamples gave the significant negative correlations with their dispersion ratio (DR), soilerodibility factors (K) and erosion ratios (ER). Also, the AI values of the soils includingclay and sandy clay loam textural class showed significant positive correlation with soilstructural stability index (SSI). It seems that the AI value may be used as an indicator ofsoil structural stability.