Optimal intraseasonal irrigation water distribution

A dynamic programming model is presented to optimise the intraseasonal distribution of irrigation water to a single crop under the constraints of limited water available and predetermined irrigation timing. The system underlying the model is characterised by two discrete state variables: the available soil-water in the root zone and the net quantity of water to be transferred to the root zone of the crop. Transition equations from one state to another are used in response to irrigation decisions. A multiplicative yield function is employed for estimating the crop yield as it is influenced by soil moisture. A numerical example is presented to illustrate the proposed procedure.