Assessing the climatic risk to crop yield of winter wheat using crop growth models

Based on validation of two crop growth models (WheatSM and APSIM-Wheat) for the winter wheat yield simulation of Beijing, winter wheat yields of multi-years were simulated by day step. According to the relationship among temperature, rainfall and simulated yields, different year types were defined and climatic risk to winter wheat production in different types of year was analyzed. Using WheatSM simulated yields, the high temperature risk to winter wheat production was assessed: when average temperature in May is over or equal to 21℃, the year of this phenological season is attributed to high temperature type and the yield will be reduced at least by 13.1% by high temperature disaster. Drought risk to wheat production was assessed using APSIM-Wheat simulated yield: when rainfall for a whole growing period is less than 100 mm and water shortage for a whole growing period is over 169.40 mm, the year is attributed to severe drought type and the yield is lower than 3.5 t·hm^-2. This study shows that the advantage of applying crop growth models to assessing climatic risk to crop production. The information obtained by climatic risk assessment provides valuable scientific basis and technological support for dynamic decision-making, and relieving the losses of winter wheat yield caused by high temperature and drought disasters, which ensures sustainable production of winter wheat in Beijing.