In situ determination of the soil surface crust hydraulic resistance

This paper proposes a new method to determine the soil surface crust resistance in situ. The method is based on the assumption that the crust is well established prior to the infiltration. In this case, and for steady infiltration regime the hydraulic resistance of the crust, can be inferred from the infiltration rate and the relationship between soil conductivity and water pressure head. The proposed method combines two types of in situ experiments: (i) rain simulation experiments; and (ii) single ring infiltration tests on the same soil after removal of the crust in order to assess the soil hydraulic properties. The effectiveness of the proposed methodology was tested by reproducing numerically the experiments. The comparison of the numerical results with observations was satisfactory. Further validation and tests on other soil types are required in order to confirm our results.