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A determina on of the parameters describing the soil hydraulic proper es of matrix and macropore domains and mass exchange between these domains is crucial when preferenal water fl ow in structured soils is simulated using the dual-permeability model. This study focused on es ma ng the parameters of the radially symmetric dual-permeability model from cumula ve infi ltra on measured in the surface horizon of a Haplic Luvisol. While parameters obtained from the numerical inversion of the tension disk infi ltra on, using the single-porosity fl ow model in HYDRUS 2D/3D, were used to describe the matrix domain, the parameters characterizing the macropore domain and mass exchange between domains were es mated using the Guelph permeameter infi ltra on and the dual-permeability fl ow model in HYDRUS 2D/3D. The mass transfer coeffi cient between the two pore domains aff ected the simulated water regime considerably, and subsequently, the calibrated value of the saturated hydraulic conduc vity in the macropore domain, K sf . A less signifi cant impact of the aggregate shape factor was observed due to a low range of possible values compared with the other two parameters, which either varied within orders of magnitude (the eff ec ve saturated hydraulic conduc vity of the interface between the two pore domains, K sa ) or were squared (the characteris c length of an aggregate, a). The K sf values increased when mass exchange decreased (when a increased and K sa decreased). Since both parameters are mutually correlated and therefore have a similar impact on simulated data, we suggest that a be determined independently, and K sa and K sf should be simultaneously op mized when the parameters of the dual-permeability model are evaluated using the presented experimental procedure.Abbrevia ons: MSO, mul step ou low; PI, ponding infi ltra on. Soil and groundwater contamina on by various chemicals used in agricul-ture and industry present a serious environmental problem that has been widely studied. b) have summarized and documented that water fl ow and contaminant transport in soils is frequently infl uenced by either water and solute temporal immobilization or preferential fl ow. Many numerical models have been developed to describe such nonequilibrium water fl ow and solute transport in soils. Commonly used physically based models simulating water fl ow and solute transport in soils use either single continuum or bi-and multicontinuum approaches. Bi-and multimodal concepts assume that the soil porous system is divided into two (or more) domains, while each domain is characterized by its own set of transport properties and equations for describing local fl ow and transport processes. Only two-domain models have been widely tested, however.Th e dual-porosity (mobile-immobile) approach (Philip, 1968;Šimůnek et al., 2003) describes water fl ow and solute transport in systems consisting of domains with both mobile and immobile water. Th e dual-porosity formulation is based on a set of equations describing water fl ow and solute transpor...

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