The Effects And Countermeasures Of Future Climate Change On Maize Yield In China

Based on the future climate scenario data,this paper analyzed the relative changes of various meteorological elements in the Huang-Huai-Hai Plain of China,and used CERES-Maize model to calibrate and validate the genetic parameters of summer maize in 9 stations and 5 sub-regions in the Huang-Hua-Hai Plain,then simulated the impact of future climate change on maize yield in the Huang-Huai-Hai Plain.In order to evaluate the contribution of countermeasures on summer maize yield under the background of climate change,the adjustment of summer maize sowing date would be taken as the main agricultural management measures in the future.It provided theoretical basis and guidance for making full use of climate resources and actively coping with the adverse effects of climate change on agricultural production.The main conclusions are as follows:?1?In the future,the precipitation in the growth period of summer maize would decrease compared with that under the Baseline period in the whole region of Huang-Huai-Hai Plain,especially in the southwest region;the solar radiation would increase relatively,especially in the west region;the maximum temperature would increase relatively,especially in the southwest region;the minimum temperature would increase relatively,especially in the northeast region.?2?Climate change would shorten the growth period of maize in the Huang-Huai-Hai Plain.The days from sowing to anthesis were 3.6d,5.4d,3.8d and 6.4d shorter than the Baseline period,under the scenarios of RCP4.5,RCP8.5 in 2030 s,2050s respectively;the days from anthesis to maturity were 8.4d,11.2d,10.6d and 13.4d shorter than the Baseline period,under the scenarios of RCP4.5,RCP8.5 in 2030 s,2050s respectively.Compared with the anthesis stage,the impact of climate change on the maturation stage was more serious.?3?Climate change had reduced summer maize yield in most areas of the Huang-Huai-Hai Plain.Under the scenarios of RCP4.5,RCP8.5 in 2030 s,2050s respectively,the yield of summer maize decreased by 19%,31.78%,35.83% and 40.95%,which compared with the Baseline period.Correlation analysis found that the future warming is the main reason for the reduction of summer maize yield,especially the maximum temperature.?4?Maize yield reduction was alleviated on the effect of CO₂ Fertilizer in the Huang-Huai-Hai Plain.Under the scenarios of RCP4.5,RCP8.5 in 2030 s,2050s,considering the effect of CO₂ fertilizer,the relative yield reduction of summer maize in the whole region were 13.49%,24.46%,30.34% and 34.61% respectively,the relative yield increased 5.51%,7.32%,5.49% and 6.34% respectively under the condition of no CO₂ fertilizer effect.The results showed that the increase of CO₂ concentration could alleviate the negative impact of climate change on yield to some extent.?5?Delaying sowing date could alleviate the yield reduction of maize in Huang-Huai-Hai Plain.This paper took the adjustment of sowing date as the main countermeasure,Under the scenarios of RCP4.5 in 2030 s,the optimal sowing date was delayed by 9d,5d,3d,4d and 1d respectively compared with Baseline period.It was mainly due to the climate warming,proper late sowing prolonged the suitable growing season for summer maize,the temperature increased at the end of maturity period,and the time of maturity period was relatively longer,which effectively alleviated the yield reduction of summer maize.