Capillary rise from saline groundwater in clay soil cores

Abstract

The rate of salinization by capillary rise from a saline water table in wet clay soil cores, 0.60, 0.75 and 0.90 m long, and 0.25 m in diameter, is described. Tensiometer-pressure potential and electrical conductivity were measured as a function of time at vertical spacings of 0.15 m. Initially a relatively rapid rise of saline water occurred to a height of 0.30 m above the water table, but subsequent movement was very slow. Although the potential evaporation rate was only 1.0 mm/day, drying of the surface occurred quickly, and proceeded down the cores, reducing the upward moisture flux to a very low value. The salinization hazard of such a soil is low, but the possibility of application of the measurement to more permeable soils, in which salinization may be more likely, is discussed.