The impact of climate variability on water footprint components of rainfed wheat and barley in the Qazvin province of Iran*

Abstract

AbstractDue to shortage of precipitation, rainfed farming in Iran is facing numerous challenges. Understanding the impact of climate variables on the production of rainfed crops in each region is of utmost importance for dry farming. Based on 11‐year (2004–2015) data from synoptic stations in the Qazvin province of Iran, a comprehensive simulation analysis was conducted with AquaCrop‐GIS to study the yield and the green and grey water footprint (WF) of the main rainfed crops (wheat and barley) along with the correlation of the target variables (yield and WF components) with the selected climate variables. Based on the estimated values of green and grey WFs, planting of rainfed wheat and barley at Qazvin and Moalem Kalayeh stations with lower total WF will be more beneficial than at other stations. Regression analysis showed that at most stations, reference evapotranspiration had a direct effect on wheat total WF (TWF), while precipitation has a positive effect on barley TWF at Qazvin and Moalem Kalayeh. The regression equation of barley green WF at the Qazvin station showed the highest correlation with climate variables (R2 = 0.98). TWF of wheat and barley at Buin Zahra had the highest correlation with climate variables (R2 = 0.73 and 0.85, respectively). Finally, it was concluded that in arid regions, the variability in TWF of rainfed products is greatly influenced by spatio‐temporal variations of climate variables. © 2020 John Wiley & Sons, Ltd.