Division of Agricultural Physics, IARI, New Delhi, 110 012.
*Water Technology Centre for Eastern Region, Chandrasedharpur, Bhubaneswar-751023.
Hydraulic characteristics of 26 dominating soil sub-groups were determined. It was observed that most of the fine textured soils belonged to Inceptisols, Vertisols and Mollisol and the coarse textured soils to Alfisols and Entisols sub-groups. Soil water retention (Ψ-θ), penetrability (P), intrinsic penetrability (Pi), sorptivity (s), weighted mean diffusivity (D) and intrinsic weighted mean diffusivity (Di) of water in the soils were determined. Out of 26 soil sub-groups, 14 had very high, 8 high, 2 medium and 2 had low water storage capacity. Very high profile water storage capacity was observed in Aeric Tropaquept, Aeric Haplaquept, typic Ustochrept, Vertic Haplaquept, Typic Ustropept, Typic Tropaquept, Vertic Haplustept, Aeric Ochraqualf, Typic Haplustalf, Aeric Fluvaquent, Lithic Ustorthent, Typic Chromustert, Typic Haplustert and Lithic Haplustoll. High profile water storage capacity was observed in Vertic Ustochrept, Typic Haplustept, Typic Paleustalf, Typic Rhodustalf, Typic Ochraqualf, Kandic paleustalf, Typic Ustorthent and Chromic Haplustert. The storage capacity was medium in Ultic Paleustalf, Rhodic Paleustalf and low in Vertic Tropaquept and Typic Ustipsamment. Water transmission properties of the soils under unsaturated condition, viz. D (θ) and K (θ), were evaluated in specially designed plexiglass columns. Scaled soil water diffusivity, D* (Θ) and pressure head, h* (Θ) versus reduced soil water content, (Θ) were developed to estimate D (θ) and h (θ) values.
Available water, Diffusivity, Scaling technique, Unsaturated hydraulic conductivity