The Relation between Fine Pores and Water Retentivity of Decomposed Granite Soil

Abstract

In order to clarify the effect of fine pores on the water retentivity of the decomposed granite soil “Masa, ” the authors have examined the relationship between porosity and water retentivity in terms of specific surface for eight samples, in various stages of weathering, stages taken from two outcrops in Shimane Prefecture.
A fine pore is first formed in specified sizes; with weathering its size becomes more variable in decomposed granite soil. At the high potential value over -1×10⁵ Pa, the fine pore content calculated from the water retentivity curves agrees approximately with that measured by the mercury injection method.