吉林省玉米干旱风险对产量的影响分析

Analysis of influence of drought risk on maize yield in Jilin Province

气候增暖背景下,干旱对吉林省玉米生产影响最大,准确评估玉米干旱风险,能够为保障吉林玉米生产安全提供科学参考。基于吉林省1961—2020年逐日气象数据、玉米发育期和产量资料,构建干旱风险指数,分析其空间分布特征,探讨其与相对气象产量的响应关系。结果表明:吉林省玉米各发育阶段干旱风险指数由西北向东南递减,播种至出苗期干旱风险最高,乳熟至成熟期干旱风险最低。干旱风险指数与相对气象产量呈负相关关系,且在抽雄至乳熟期相关系数绝对值最大。吉林西部最大综合干旱风险指数普遍在2.5以上,能够造成7成玉米减产;吉林中部最大综合干旱风险指数在2.0左右,灾损率可达5成。在吉林省西部和中部,抽雄至乳熟期干旱风险指数、综合干旱风险指数与相对气象产量均呈开口向下的抛物线关系。当综合干旱风险指数较小(0.0~2.0)时,相对气象产量正负值不确定性较大。当综合干旱风险指数较大(2.0~4.0)时,相对气象产量呈明显下降趋势,玉米灾损率明显增大。

Under climate warming,drought is still the most serious agro-meteorological disaster affecting maize production in Jilin Province.Accurately assessing drought risk and grasping the quantitative relationship between drought risk and yield could provide sci⁃entific reference for ensuring the safety of maize production.Based on the daily meteorological data,maize developmental stages and maize yield data from 1961 to 2020 in Jilin Province,the drought risk index of maize was constructed,its spatial distribution character⁃istics were analyzed.Moreover,the response relationship between relative meteorological yield and drought risk index was discussed.The result show that drought risk index of maize at each developmental stage decreased successively from northwest to southeast in Jilin Province.During maize growing season,drought risk was the highest at the stage from sowing to seedling,while it was the lowest at the stage from milking to maturing.Drought risk index had negative correlation with relative meteorological yield of maize.Furthermore,ab⁃solute value of correlation coefficient was the largest at the stage from tasseling to milking.The maximum comprehensive drought risk index was generally above 2.5 in the west,which might cause nearly 70%loss of maize yield.Besides,maximum comprehensive drought risk index in the middle was about 2.0,and disaster loss rate could reach 50%.In the western and central parts of Jilin Prov⁃ince,relationship between drought risk index from tasseling to milking and relative meteorological yield was a parabola going down⁃wards,as well as the relationship between comprehensive drought risk index and relative meteorological yield.If comprehensive drought risk index was between 0.0 and 2.0,relative meteorological yield might be positive or negative.If comprehensive drought risk index was between 2.0 and 4.0,relative meteorological yield showed a downward trend,and disaster loss rate increased obviously.