Soil-water movement in water-saturated capillary porous media

Abstract

The movement of water through capillary porous media (soils) saturated with water is quantitatively described by the Darcy equation; its application to water flow and water-potential distribution for various configurations of soil samples is described. The Darcian approach to saturated soil-water movement assumes the porous space is fully saturated with water; the soil pores do not change their dimensions, and soil temperature is constant. Hydraulic conductivity and permeability of soils saturated with water are defined and a wide variety of its measurement methods is presented. The frequently used methods for the measurement of the saturated hydraulic conductivity of soil samples in the laboratory are described in detail. Field methods for the measurement of saturated hydraulic conductivity above the groundwater table are presented and discussed. Pedotransfer functions to evaluate hydraulic conductivity from available data are briefly discussed.