Furrow Irrigation Performance under Spatially Varying Conditions

A zero-inertia furrow irrigation model with specified space solution was used to investigate the effects of variability in furrow inflow rate and spatial variability in infiltration, geometry, and roughness on end-of-furrow advance, average infiltrated depth, and Christiansenʹs and distribution uniformities. Extensive field-gathered infiltration, geometry, and roughness data were used as input to the zero-inertia model. Simulations were performed on a single furrow as well as fieldwide. Variable furrow inflow was incorporated into the fieldwide analysis. Model simulations were evaluated to determine the importance to irrigation performance of variability in each input variable. Variability of furrow physical characteristics, in decreasing order of their relative impact on furrow irrigation performance, were furrow inflow rate, infiltration, geometry, and roughness for the conditions studied.