MODEL FOR OPTIMAL CROPPING PATTERNS WITHIN THE FARM BASED ON CROP WATER PRODUCTION-FUNCTIONS AND IRRIGATION UNIFORMITY .1. DEVELOPMENT OF ADECISION-MODEL

A model has been developed to determine optimal irrigation strategies for a single season. This has been achieved by using a simple relation between yield and amount of irrigation water which takes into account the effect of uniformity of water application. The main objective of the model is to provide a procedure by which farms can evaluate and co mpare alternative assumptions on expected water regimes for the follow ing year in order to optimize crop rotations, crop production and farm incomes and to attain the optimum use of irrigation works, farmland a nd other resources. The method requires data that are readily availabl e to the farmer.