CO2 and temperature dominate the variation characteristics of wheat yield in China under 1.5 °C and 2.0 °C warming scenarios.

Under the 1.5 °C and 2.0 °C warming scenarios, few studies have explored the different influences of CO2, temperature, and precipitation on wheat yield in China. Hence, we analyzed the different influences of above factors on wheat yield after analyzing the wheat yield change. Results show that (1) the wheat yield of China would increase under the two warming scenarios. The spring wheat yield of the Northeast Spring Wheat Region (DB_S) and the Northwest Spring Wheat Region (XB_S) would increase more than that in the other two spring wheat-planting subregions. The winter wheat yield of the Southwest Winter Wheat Region (XN_W) and Middle and Lower Yangtze Winter Wheat Region (CJ_W) would increase more significantly compared with that in the other three winter wheat-planting subregions. (2) CO2 fertilization was identified as the main factor leading to a wheat yield increase, with an estimated increase of 12–18% under the 1.5 °C warming scenario and 18–21% under the 2.0 °C warming scenario. (3) Without considering CO2 fertilization, compared with precipitation, temperature dominated the spatial patterns of the wheat yield responses to climate change. Temperature influence on wheat yield was mainly reflected in the amplitudes of yield increase, while precipitation mainly affected the proportion of yield-increasing area. For wheat-planting regions with less precipitation, such as the North Spring Wheat Region (BB_S) and the Huang-Huai Winter Wheat Region (HH_W), the wheat yield increase caused by precipitation was usually more pronounced. Our findings would help inform policy decisions related to wheat production in China to better cope with future climate warming. [ABSTRACT FROM AUTHOR]