The measurement of stability of soil micro-aggregates in water

Abstract

The value of aggregation (0.05 mm.) corresponding to some specific shaking time is a satisfactory index of structure stability. Where the effects of different cultural treatments on the structure of a soil were being considered, shaking for short periods showed to advantage over long periods. The results obtained by shaking end-over-end for a short period were reproducible. There is an approximate exponential relationship between time of shaking and aggregation (0.05 mm.). The slope of the line obtained by plotting aggregation (0.05 mm.) against logarithm of time was considered as a supplementary index of stability but it appeared to give little additional information. Comparisons were made between hand and machine shaking and between capillary and flood wetting. Capillary wetting was found more satisfactory than flood wetting. The effect of altering the volume of suspension contained in a given cylinder was examined.