ABSTRACT
Abstract Two major factors influencing the performance of in-field irrigation are volume and timing of water delivery. Both of these factors can be fixed or adjusted to meet crop water demands. Irrigation delivery scheduling with a supply-oriented approach often results in large losses of water because it does not reflect the actual crop water requirements. This paper discusses the application of the delivery scheduling module of SIMIS (for Scheme Irrigation Management Information System), developed by FAO, to irrigation systems in Argentina and Thailand, with their very different environments, in a check of its capabilities. Simulation of different delivery scheduling options was done for comparison of their results so that potentials and limitations of demandoriented management can be clearly understood. Keywords: Demand management, irrigation delivery scheduling, water saving
1 Introduction
From the point of water delivery to farmers' fields, it is very important to supply the appropriate amount of water at right timing so that optimum agricultural production can be obtained. The timing or interval and volume of water supply to the field can be defined by irrigation scheduling at farm level. Scheduling can be very flexible when both variables (timing and volume) are changeable, and can be very rigid when both are fixed. The complexity of operation and the burden of operator increase as the freedom of water use increases. Which scheduling methods to adopt in an irrigation system depends on the infrastructural setup and managerial capabilities as well as local conditions surrounding an irrigation system/irrigated agriculture.
