ABSTRACT
Unsaturated hydraulic conductivity – the pressure head relationship K(h) – is one of the basic functions connected with water flow and pollution transport in soils. Many methods – both in the field and laboratory – have been developed and tested over time for the direct determination of this curve (e.g. Gardner 1956, Hillel et al. 1972, Stephens 1985, Stolte et al. 1994, Butters & Duchateau 2002, Fujimaki & Inoue 2003, Meadows et al. 2005), but they are expensive and timeconsuming (e.g. Russo & Bresler 1981, Vereecken 1995, Chen & Payne 2001, Minasny et al. 2004, Lazarovitch et al. 2007). Hence, estimation methods for the determination of K(h) based on more easily measured soil parameters has gained popularity and have been developed in parallel with the direct methods.
