Toward a simple real-time control system for efficient management of furrow irrigation

A simple real-time control system for furrow irrigation is proposed that predicts the infiltration characteristic of the soil in real time using data measured during an irrigation event, simulates the irrigation, and determines the optimum time to cut-off for that irrigation. The basis of the system is a new method for estimating the soil infiltration characteristic under furrow irrigation, previously developed by the authors, that uses a model infiltration curve, and a scaling process to predict the infiltration characteristic for each furrow and each irrigation event. Using the new method, infiltration parameters were calculated for two different fields. The SIRMOD simulation model was then used to simulate irrigation performance under different model strategies. These were framed to assess the feasibility of, and demonstrate the gains from, the real-time control strategy. The simulation results showed that the system is feasible. The scaled infiltration gave predictions of the irrigation performance comparable to the measured performance, clearly establishing the suitability of this method for use in real-time control. The results further indicated that under simple real- time control the irrigation performance for the two fields could be greatly improved with reductions in the total volume of water applied to the two fields of 20 and 60% respectively, indicating the scale of benefits that can be achieved in the irrigation sector by implementing simple real-time control. Copyright (c) 2007 John Wiley & Sons, Ltd.