Impact of Future Climate Change on Wheat Production: A Simulated Case for China's Wheat System

With regard to global climate change due to increasing concentration in greenhouse gases, particularly carbon dioxide (CO2), it is important to examine its potential impact on crop development and production. We used statistically-downscaled climate data from 28 Global Climate Models (GCMs) and the Agricultural Production Systems sIMulator (APSIM)-Wheat model to simulate the impact of future climate change on wheat production. Two future scenarios (RCP4.5 and RCP8.5) were used for atmospheric greenhouse gas concentrations during two different future periods (2031-2060 referred to as 40S and 2071-2100 referred to as 80S). Relative to the baseline period (1981-2010), the trends in mean daily temperature and radiation significantly increased across all stations under the future scenarios. Furthermore, the trends in precipitation increased under future climate scenarios. Due to climate change, the trend in wheat phenology significantly advanced. The early flowering and maturity dates shortened both the vegetative growth stage (VGP) and the whole growth period (WGP). As the advance in the days of maturity was more than that in flowering, the length of the reproductive growth stage (RGP) of spring wheat was shortened. However, as the advance in the date of maturity was less than that of flowering, the RGP of winter wheat was extended. When the increase in CO2 concentration under future climate scenarios was not considered, the trend in change in wheat production for the baseline declined. In contrast, under increased CO2 concentration, the trend in wheat yield increased for most of the stations (except for Nangong station) under future climatic conditions. Winter wheat and spring wheat evapotranspiration (ET) decreased across all stations under the two future climate scenarios. As wheat yield increased with decreasing water consumption (as ET) under the future climatic conditions, water use efficiency (WUE) significantly improved in the future period.