Fig. 4

Drying and wetting retention curves of two sandy soils: Edosaki soil with initial dry density of 1220 kg m^–3 (a) and with initial dry density of 1350 kg m^–3 (b); Chiba soil with initial dry density of 1250 kg m^–3 (c) and with initial dry density of 1420 kg m^–3 (d) with medium capillary radii, r_i and the corresponding water contents, Δθ_i, i = 1.2,…,5, and with linear equations fitted into the individual zones with a boundary effect stage, a transition stage with an inflection point, and a residual stage. The experimental data are derived from Gallage et al.⁴⁵.