Prüfung von 3 Verfahren zur Vorhersage der hydraulischen Leitfähigkeit ungesättigter Böden aus Wasserretentionsdaten oder aus der Bodenart

Testing of three methods to predict unsaturated soil hydraulic conductivity from water retention data or from texture class Using 60 soils taken from UNSODA (Leij et al., 1996) the method proposed by Renger et al. (1999) and the prediction according to Mualem (1976)/van Genuchten (1980) were tested. The parameters of the Mualem/vanGenuchten model were estimated either from water retention data or from a table of reference values. Using the reference values requires only the knowledge of texture class (German classification system). An advantage of the method proposed by Renger et al. (1999) is its capability to predict saturated conductivity too. The model of Mualem/vanGenuchten using reference values of parameters yields the best results. The standard deviation between observed and predicted values of unsaturated hydraulic conductivity was 0.93 lg (K) for the Mualem/vanGenuchten model and 1.3 lg (K) for the Renger et al. (1999) predictions.