1987-2016年石羊河流域太阳辐射及气温变化对春玉米产量的影响

Impact of Variation in Solar Radiation and Temperature on Potential Yield of Spring Maize in Shiyang River Basin in 1987-2016

【目的】更好地应对气候变化对西北春玉米生产的影响。【方法】通过全局组合方法,基于30 a历史气象资料,将每年生育期内的气象因子分为日平均气温(Ti)、日太阳辐射(Si)及其余气象因子(Xi)3个独立的时间序列,第i年气象资料可看作集合[Ti,Si,Xi],然后分别对集合[Ti,(X,S)i]及[Si,(X,T)i]中的因子进行年际组合,进而生成1800个气候情景,借助RZWQM2模型对各情景下的作物潜在产量进行模拟,研究分析了石羊河流域1987-2016年春玉米生育期内(5-9月)平均日太阳辐射、日最低气温、日最高气温及日均气温的年际变化趋势。【结果】①生育期内平均日最高、最低及平均气温,均呈显著上升趋势,增加速率为0.04、0.14、0.09℃/a。②生育期内日太阳辐射在14.6~17.4 MJ/(m^2·d)间波动,变化趋势不明显。③1987-2016年该地区春玉米潜在产量(不含水分)在7261~11248 kg/hm^2波动变化,随时间先增加后减小,最大值出现在2002年左右。【结论】气温是影响玉米产量的主导因子,气温的持续性升高已造成潜在产量的降低,其中,日最高气温对潜在产量的影响最为显著。

【Objective】In order to improve our understanding of the impact of climate change on spring maize production in northwest China,this study analyzed the trend of daily solar radiation,daily minimum air temperature,daily maximum air temperature and daily average air temperature during the growth season of spring maize(May-September)in Shiyang River Basin from 1987 to 2016.【Method】The meteorological data during maize growth season in each year were divided into three time series:Daily average air temperature(Ti),daily average solar radiation(Si)and daily average meteorological factor(Xi).Inter-annual combinations of[Ti,(X,S)i]and[Si,(X,T)i]generated 1800 climate scenarios,and the potential crop yield in each scenario was simulated with the RZWQM2 model.【Result】①The daily maximum air temperature(TH),daily minimum air temperature(TL)and daily average air temperature(TM)all trended upwardly,rising at annual rate of 0.04℃,0.14℃and 0.09℃respectively.②The daily solar radiation fluctuated between 14.6 and 17.4 MJ/(m^2·d).③In 30 years period,the potential yield of spring maize in this region fluctuated between 7261 and 11248 kg/hm^2,increasing initially followed by decline after peaking in 2002.【Conclusion】Temperature is the most important factor affecting maize yield and the continuous rise in temperature had led to a decrease in potential yield.Among all meteorological factors,the daily maximum air temperature affected the potential yield most.