Farmerless Profit-Oriented Irrigation Scheduling Strategy for Solid Sets. I: Development

Abstract

Liberalization of agricultural markets is changing the irrigation focus from maximizing yields to maximizing profits. This study was conducted to develop a self-programmable irrigation scheduling strategy for solid sets aimed at improving profits. It is based on simulation models and water and crop prices. The economic optimization of solid-set irrigation is constrained by the fact that the efficiency is not previously known because of the unpredictability of seasonal weather and the accumulated effect of nonuniform irrigations in the soil water depletion (SWD) uniformity. Consequently, seasonal revenue and cost functions cannot be determined. The strategy addresses this constraint by (1) refilling SWD under weather conditions that minimize water losses when crop is not water stressed and SWD is high and uniform enough to prevent percolation; and (2) estimating revenue and cost functions for each irrigation event in order to determine the economically optimal water depth when SWD uniformity is so low that percolation and/or crop water stress are unavoidable. The strategy is presented in this paper and assessed under different conditions in the companion paper.