Experimental Verification of the Recently Proposed Calculation Methods for the Two Parametric Diffusivity—Water Content Functions

Recently proposed nomographic interpretation of the water absorption data in terms of the two parametric diffusivity water content functions was tested experimentally for clay, sandy loam and loamy sand soils. Experimental values agreed well with the values calculated using the nomographs. The constants in the D (diffusivity)-θ (water content) relationship as a power function were also calculated according to the modification of the nomographic interpretation suggested by Parlange. Parlange's theory of horizontal infiltration was tested by back calculating the λ (Boltzmann variable)-θ curves from the experimental D-θ values. The K (conductivity)-θ relations were calculated using the D-θ values and the pF curves of the soils. The K-θ values thus found were compared with those expected from the recently proposed scaling technique of Reichardt et al.