Theoretical Relationship between Saturated Hydraulic Conductivity and Air Permeability under Dry Conditions: Continuum Percolation Theory

The saturated hydraulic conductivity, Ks, is a fundamental characteristic of subsurface flow and the hydrologic cycle. However, direct measurement of Ks is time consuming. Recently, air permeability measurements at 50 and 100 cm of H2O tension, a relatively dry condition in coarse and medium‐texture...

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Bibliographic Details
Main Authors: Behzad Ghanbarian, Allen G. Hunt, Robert P. Ewing, Thomas E. Skinner
Format: Article
Language:English
Published: Wiley 2014-08-01
Series:Vadose Zone Journal
Online Access:https://doi.org/10.2136/vzj2014.03.0029
Description
Summary:The saturated hydraulic conductivity, Ks, is a fundamental characteristic of subsurface flow and the hydrologic cycle. However, direct measurement of Ks is time consuming. Recently, air permeability measurements at 50 and 100 cm of H2O tension, a relatively dry condition in coarse and medium‐textured soils, have been used to estimate Ks. In this short communication, we present a theoretical framework for relating Ks to ka(ϕ), the air permeability as a function of porosity, ϕ, under completely dry conditions. We used power‐law scaling from continuum percolation theory to develop a theoretical relationship between Ks and ka(ϕ). Our result, similar in form to a published logarithmic equation with empirical coefficients, gives a physical interpretation to these empirical coefficients.
ISSN:1539-1663