Using Two Pedotransfer Functions to Estimate Soil Moisture Retention Curves From One Experimental Site of ​​South Moravia

Abstract

The soil moisture retention curves (SMRCs) were measured in laboratory conditions. The sand table and pressure extractor method were used to obtain a 9-point SMRCs for undisturbed soil samples taken from 20 cm depth. The data points of the individual retention curves were parameterized using the RETC computer program. For the same soil, the SMRCs were estimated by two models of pedotransfer functions (PTFs). In the first part of the study the Rosetta program with the model of artificial neural network (Schaap et al., 1998) was used. The PTFs derived by Wösten et al. (1998) were used in the second part of the study. The reliability of selected PTFs models were tested on local soils from one site of the South Moravia. The quality of estimated retention curves was evaluated using the coefficient for correlation R between the measured and the estimated soil water content at several pF values and the root mean squared error RMSE. Of the two models of PTFs, which have been tested in the study, Wösten’s model showed better agreement with the measured retention curves (RMSESch = 0.0383 (cm3.cm−3), RMSEW = 0.0264 (cm3.cm−3)).

Keywords

• soil moisture retention curve
• soil hydraulic properties
• pedotransfer functions
• artificial neural networks