Optimal Spatial and Temporal Allocation of Irrigation Water for Cotton In Texas High Plains

Optimizing the spatial and temporal allocation of irrigation water in cotton is critical for Texas High Plains’ cotton farmers who depend heavily on the Ogallala aquifer for irrigation needs.  Crop simulation models are an effective tool to simulate crop yield under various climate, soil, and management conditions. In this study, the synthetic weather data generator US-CLIMATE was used to simulate the possible weather conditions in Texas High Plains for 60 years. Cotton2K, a cotton growth simulation model, was then used to simulate the yield each year under 80 different irrigation strategies in a center pivot irrigated cotton field. The irrigation strategies combine 10 temporal allocation treatments and 8 spatial allocation treatments.  The resulting dataset was used in an economic model to determine the profit-maximizing spatial and temporal allocation of irrigation water. Additionally, a sensitivity analysis was conducted to examine the effect of cotton price on the optimal water allocation strategy.