Applying the economic water use efficiency concept to determine the optimal cropping pattern in Rayen City

Despite of having a favorable condition for many agricultural crops, Iran faced severe water shortage due to improper cropping pattern in many parts of the country. In this study, the concept of water use efficiency (WUE) and economic water productivity (WPe) was applied to prioritizing four common cultivated crops in Rayen city; including wheat, corn, alfalfa and barely. Crop water use was calculated by multiplying the crop coefficient by the reference evapotranspiration during the growing season. Having yield at final harvest and the net income per unit produced crops, the WUE and WPe was calculated for all crops. Results showed that the lowest and the highest WUE was for wheat (0.94 kg m-3) and alfalfa (1.56 kg m-3), respectively. Also, corn with net income of about 75 million Riyal ha-1 and barely with net income of about 40 million Riyal ha-1 took the first and the last place, respectively, with respect to net income. Thus, corn WPe was higher than wheat and barley. So that corn cultivation would led to higher benefits in compare with the other crops in the study area. Based on the results, corn cultivation is encouraged due to high net income, WUE and WPe.

Alfalfa, Barely, Corn, Wheat, Water Use Efficiency, Optimal Cropping Pattern