Effect of sediment transport, flow depth and infiltration on soil moisture profiles in irrigation furrows

Abstract

A numerical model was used to analyze the effect of sediment transport and flow depth on soil moisture profiles from a simulation of the hypothetical irrigation furrows. The Saint Venant and sediment continuity equations were solved by using MacCormack scheme based on finite difference method to analyze the overland flow and sediment transport, and Richards equation was used to analyze the subsurface flow, which was solved by using a mass conservative fully implicit finite difference method. Flow depth significantly affected the moisture profiles in irrigation channels while the effect of sediment-laden water on the moisture profiles was observed insignificant. The model was used to study the effect of infiltration on moisture profiles and soil water retention curve (SWRCs) in irrigation furrows. It was observed that infiltration significantly affected and altered the moisture profiles and soil water retention curve (SWRC). Among the different soil parameters (av and nv ) and saturated hydraulic conductivity () significantly affected the moisture profiles, while and influenced the soil water retention curve (SWRC) as compared to other retention parameters.