Laboratory evaporation experiments in undisturbed peat columns for determining peat soil hydraulic properties

Hydraulic properties of mineral and organic soils differ in several aspects. Due to the high amount of organic components, strong heterogeneity, and shrinkage and swelling of peat, accompanied by changing soil volume and bulk density, modelling of water flow in peat soils with Richards' equation and the commonly applied van Genuchten-Mualem (VGM) parameterization is difficult. We determined hydraulic properties from various peat soils, covering a broad range of degradation states and land use histories, by laboratory evaporation experiments and evaluated the applicability of VGM to describe measured water content and pressure head data by inverse modelling of the experiments.