Temperature increase may not necessarily penalize future yields of three major crops in Xinjiang, Northwest China

Abstract

Future food production is at risk due to climate change, particularly in arid regions with limited water resources and extensive irrigated agriculture. This study utilized the DSSAT model in conjunction with downscaled data from 21 global climate models (GCMs) under two shared socioeconomic pathways (SSP2–4.5 and SSP5–8.5) to assess the impact of projected climate change on irrigated crop phenology, yield, and evapotranspiration (ET_c) of cotton, maize, and winter wheat in the Shihezi region of Xinjiang, China. The results indicated that temperature and precipitation in the region were expected to increase gradually from 2021 to 2100. Climate change has resulted in earlier anthesis and physiological maturity of all three crops. Future climatic conditions could reduce maize yields to 16.02 %. Conversely, the yields of cotton and winter wheat increased, with cotton yields rising by 1.23–10.94 % and winter wheat yields by 3.19–14.07 %. Additionally, ET_c for cotton, maize, and winter wheat could rise in the future. The irrigation water demands could increase by 41.1–96.4 mm for cotton and 27.3–37.9 mm for maize, while the demand for winter wheat could decrease by 0.5–36.2 mm. Warming was significantly correlated with the changes in the yield and water use efficiency (WUE) of cotton, maize, and winter wheat. The temperature increases of +0.5°C to +3.0°C (relative to baseline) at 0.5°C intervals were analyzed to evaluate their effects on yield and WUE. The yields varied from −0.93 % to 6.15 % for cotton, −43.42 % to −7.99 % for maize, and 4.28–9.92 % for winter wheat. The WUE changes ranged from −29.03 % to −1.08 % for cotton, −43.06 % to −7.66 % for maize, and 0.69–3.47 % for winter wheat. Contrary to the common belief that rising temperatures generally harm crop yields, our study suggests that temperature fluctuations may benefit certain crops in specific regions. These results could provide theoretical guidance for implementing adaptive measures to future climate change in regions with conditions similar to Shihezi, Xinjiang, China, to ensure crop security and sustainable water management.