The effect of allocation schedules on the performance of irrigation systems with different levels of spatial diversity and temporal variability

Abstract This paper quantitatively examines the effect of spatial diversity and temporal variability on the performance of an irrigation system. The Irrigation Land Management (ILM) computer model was used to simulate over a 20-year period the response of four test systems constructed with different levels of spatial diversity and temporal variability to three schedules representing different levels of management flexibility. From the simulation runs it is apparent that the need for more flexible schedules becomes greater as the irrigation system becomes more spatially diverse and its climate becomes more variable. Choosing the right schedules depends not on maximizing production, but rather on optimizing production given the costs of management and the context within which the system operates.