Impacts of climate change on winter wheat production in China

Climate is changing due to increasing concentration of greenhouse gases, affecting many economic sectors, e.g. agriculture and forestry. Agriculture is a basic sector, especially to China with the most population. Wheat is the second most important staple crops in China. Therefore, assessment of the impacts of climate change on winter wheat is essential for policy maker and wheat producers for adapting to climate change. CERES-Wheat, a dynamic process crop growth model, that had been tested in assessing the impact at three sites in the major winter wheat growing regions of China was linked with Regional Climate Model (RCM)-PRECIS to simulate the change of the production under the IPCC SRES greenhouse gases emission A2 and B2 scenarios. Changes in rainfed and irrigated winter wheat under the changing climate without and with CO₂ fertilization effect were simulated respectively. The results of the study are summarized as following: (1) the output of the regional climate model -PRECIS- can be directly used to drive the CERES-Wheat model that has been effectively validated in China. (2) If the CO₂ fertilization effect was not included, the average and total yield of rainfed and irrigated winter-wheat would decrease in Northwest China under both A2 and B2 scenario. If the CO₂ fertilization effect was included in the simulation, the rainfed and irrigated winter wheat yield will increase to some extent in all over China under both A2 and B2 scenarios. (3) The rainfed wheat would be more sensitivity than the irrigated wheat to climate change and hence should receive more attention.