Potential impact of climate change on rainfed wheat production in Iran

Abstract

Mean monthly weather data values from 1968 – 2000 for 12 major rainfed wheat production areas in north-west and western Iran were used with a climate model, United Kingdom Meteorological Organization (UKMO), to predict the impact of climate change on rainfed wheat production for years 2025 and 2050. The crop simulation model, World Food Study (WOFOST, v 7.1), at CO₂ concentrations of 425 and 500 ppm and rising air temperature of 2.7 – 4.7°C, projected a significant rainfed wheat yield reduction in 2025 and 2050. Average yield reduction was 18 and 24% for 2025 and 2050, respectively. The yield reduction was related to a rainfall deficit (8.3 – 17.7%) and shortening of the wheat growth period (8 – 36 d). Cultivated land used for rainfed wheat production under the climate change scenarios may be reduced by 15 – 40%. Potential improvements in wheat adaptation for climate change in Iran may include breeding new cultivars and changing agronomic practices like sowing dates.