气候变化对河北省宁晋县夏玉米产量的影响

Effects of climate change on yield of summer maize in Ningjin County of Hebei Province

利用M-K检验和Sen斜率对河北省宁晋县1982—2018年的气象数据和对应年份的玉米产量数据进行分析,并利用HP滤波法将夏玉米产量分离为气候产量和趋势产量,进而分析气候产量与气候变化的关系,筛选产量变化较大的年份,分析气象因子的变化特征,进而解释夏玉米生产主要的气象影响要素。结果表明:夏玉米种植季总日照时数、相对湿度以及风速呈显著下降趋势,下降幅度分别为3.76 h·a^(-1)、0.10%·a^(-1)和0.01 m·s^(-1)·a^(-1),平均气温和最低气温呈显著上升趋势,上升幅度分别为0.03℃·a^(-1)和0.05℃·a^(-1);玉米实际产量和趋势产量均呈显著上升趋势,实际产量多年平均值为4997 kg·hm^(-2),气候产量变化范围为^(-1)649~932 kg·hm^(-2);分析典型高产年和低产年气候要素得出,降水不足,尤其是抽雄~成熟期降水不足,及播种~拔节期极端高温会造成玉米减产,如1986年和1991年抽雄~成熟期降水量比多年平均值少32%和43%,造成减产56%和29%,2009年播种~拔节期(6月24—29日)日最高气温为40℃左右,8月20日以后,降水量达到了207 mm,苗期过高的气温以及生育后期过多的降水也使得产量降低了25%。玉米生育期稍微偏低的气温,尤其是拔节~成熟期偏低的气温以及充足的降水有利于玉米高产。

The impact of climate factors on summer maize yield in typical years in plain area of Hebei Province,especially the impact of extreme climate factors,plays an important role in stable yield and high-yield management of summer maize.In this study,M-K test and Senslope were used to analyze the climateand yield data of summer maize growth period from 1982 to 2018 in Ningjin County of Hebei Province.The summer maize yield was separated into climatic yield and trend yield by using HP filter.Then the relationship between climatic yield and climate change was analyzed.The years with large yield changes were selected,and the main climate factors were revealed.The results showed that the total sunshine hours(3.76 h·a^(-1)),relative humidity(0.10%·a^(-1))and wind speed(0.01 m·s^(-1)·a^(-1))in maize planting season decreased significantly,and the average temperature(0.03℃·a^(-1))and minimum temperature(0.05℃·a^(-1))increased significantly.The annual average of actual maize yield was 4997 kg·hm^(-2),and the range of climatic yield was^(-1)649~932 kg·hm^(-2).The actual yield and trend yield showed a significant upward trend.Analysis of the impact of climate factors on summer maize yield in typical high yield and low yield years indicated that insufficient precipitation,especially at tasseling-maturity period,and extreme high temperature at sowing-jointing period significantly affected maize yield.In 1986 and 1991,the precipitation from tasseling to maturity was 32%and 43%less than the annual average,resulting in 56%and 29%yield reduction.From June 24 to 29 of 2009 during sowing to jointing period,the daily maximum temperature was about 40℃.After August 20,the precipitation reached 207 mm.The high temperature at seedling stage and excessive precipitation at later growth stage also reduced the yield by 25%.In summary,the slightly lower temperature during maize growth period,especially at jointing-maturity period and sufficient precipitation were beneficial to maize yield.