Analysis and Future Study of 60-Year Temporal Variations of Water Use Efficiency of Irrigated Wheat in Tabriz Plain

Considering the importance of enhancing water use efficiency in the production of crops in the Iran; and due to the appropriateness of time series methods in the analysis and future studies of the behavior of water engineering phenomena, the aim of this study was to analyze and future study of water use efficiency in wheat production in Tabriz plain with suitable time series models. The modeling (based on 30 years data), test (based on 12 years data) and future study (based on 18 years data) were made with 60 years (from 1354/1975 to 1413/2034) water use efficiency in wheat production. Fourteen time series models were evaluated to determine the suitable model. Based on common statistics, ARIMA (1,0,1) was detected as the most suitable model for water use efficiency in wheat production in Tabriz plain. Results revealed that water use efficiency in wheat production had approximately an increasingly trend. This index was from 0.11 to 0.68 kg m-3 with an average of 0.32 kg m-3. Scenarios and various promotion conditions were also considered to improve the water use efficiency in wheat production. If the water use efficiency in wheat production is increased by as much as 10, 15, 20 and 25 percent, then the index in the year 1413/2034 will be respectively equal to 0.95, 0.98, 1.01, and 1.05 kg m-3. With the continuation of the current trend and without applying the any improvement plan, the value of this index will be 0.89 1.05 kg m-3 in 1413/2034. Applicable procedure and solutions were proposed to significantly enhance water use efficiency in wheat production in the east of Urmia Lake.