Effects of Climatic Change on Maize Varieties Distribution in the Future of Northeast China

Rising ground temperature as a part of climate change has a considerable influence on the climate and environment. Northeast China, as one major grain area ensuring the food security in China, suffers serious impacts of the climate change. Traditional cultivation ways cannot adapt the new situation, leading to an increasing instability of the agricultural system. The planting system, structure and layout cannot match the original climatic resources. The research adopts the RCPs situation instead of the original SRES scenarios data, to provide a reasonable variety selection, and a scientific basis for dealing with the climate change in the future. To explore effects of future climate change on maize varieties and climatic potential productivity in Northeast China, simulations are carried out with regional climate model, using two emission scenarios RCP4.5, RCP8.5 during 2011-2099, and daily observations of 91 stations during 1961-2010. A series of analysis are carried out on the temporal and spatial distribution of maize variety, climatic potential productivity, resource utilization ratio under the situation of climate change in the future. The result shows that in the baseline scenario (1961-2010), the late maturing varieties can be planted in smaller southern areas, while they cannot grow in northern areas. Under the condition of RCP4.5 and RCP8.5(2011-2099), suitable areas for late maturing varieties will expand, and in RCP8.5, the suitable areas are the largest. The climatic potential productivity in Northeast China is high in the south while low in the north. In the baseline scenario, the annual production is 10492.54 kg·hm^-2, and in RCP4.5 it increases to 10697.16 kg·hm^-2, while in RCP8.5 it drops to 9410.17 kg·hm^-2. The maize potential productivity increases with this climate change trend in the whole area. In the baseline scenario, the radiation suitability is highest but the temperature suitability is lowest for maize production. With the climate change, the radiation suitability and temperature suitability both increase, but the water suitability will decrease to 0.63 and 0.48 in scenarios of RCP4.5 and RCP8.5, which will become a main factor that restricts the production of crop in Northeast China. In the baseline scenario, the resource utilization rate is 0.826, and its growth rate is 0.009/(10 a). In the situation of RCP4.5, RCP8.5, they are 0.804 and 0.647, and growth rates are 0.010/(10 a) and -0.002/(10 a). Suitable areas for late maturing varieties expand evidently, but the potential productivity of maize and resources utilization declines. It should also be noted that the regional climate model may bring uncertainties to results.