Analysis of Hydraulic Resistance of Soil Surface Seals in Relation to Sediment Particle Size

Surface sealing, and their role in runoff and erosion, especially, in agricultural fields have been recognized as major set-backs to irrigation operations. Though the process is restricted to only the topmost soil layer of some few millimetres in depth, surface sealing can substantially impede the infiltration of water into the soil. However, information on this process is much less documented. The aim of this study was to investigate the possible relationships between seal type and hydraulic resistance. The paper presents a simple theoretical approach which allows the estimation of changes in hydraulic resistance at the soil surface as a function of time following the formation of surface seals formed from different sediment particles at different concentrations in suspension. A laboratory column studies was designed to investigate the effects of water quality on infiltration rate. Clear water, and muddy water comprising sand, silt and clay at different concentrations of 10, 20, 30 and 40 g in 400 cm3 of water were used as the test fluids.