宁乡烟区界限气温及生育期气温变化特征研究

Study on the variation characteristics of boundary temperature and growth period temperature in Ningxiang tobacco area

以1991-2020年宁乡市逐日气象观测数据为基础资料,采用趋势分析和Mann-Kendall突变检测等方法,分析宁乡烟区界限气温和生育期气温的变化特征。结果表明:(1)近30年来,气温稳定通过8、13℃的初日显著提前,日均温小于8和13℃的日数显著减少;最高气温超过35℃的首日显著提前,且出现35℃气温的日数呈增加趋势。(2)伸根期、旺长期和成熟期日均温均呈升高趋势,线性拟合倾向率每10年分别达1.51、0.57和1.18℃,其中伸根期和成熟期日均温变化达显著水平,分别于1999和2007年后发生突变。总体上宁乡烟区烤烟伸根期气温升高和通过8、13℃初日提前有利于烤烟早生快发,而成熟期气温升高和35℃首日提前会增加烤烟高温逼熟的风险。根据以上变化,有必要在试验的基础上优化烤烟生产的物候期。

Based on the daily meteorological observation data of Ningxiang from 1991 to 2020,the variation characteristics of boundary temperature and growth period temperature in Ningxiang tobacco region were analyzed by trend analysis and Mann-Kendall mutation detection.The results show that:(1)In recent 30 years,the first day when the temperature was stable through 8 and 13℃is significantly advanced,and the number of days when the daily average temperature is less than 8 and 13℃was significantly reduced;The first day when the maximum temperature exceeded 35℃was significantly advanced,and the number of days when 35℃appears is increasing.(2)The average temperature in the root extension stage,the long-term average temperature and the mature stage average temperature all showed an increasing trend,and the linear fitting tendency rates per 10-year reached 1.51,0.57 and 1.18℃respectively.Among them,the average temperature changes in the root extension stage and the mature stage reached a significant level,and mutations occurred after 1999 and 2007 respectively.In general,the rise of temperature in the root extension period and the advance of the first day through 8 and 13℃in Ningxiang tobacco area will be conducive to the early growth and rapid development of flue-cured tobacco,while the rise of temperature in the maturity period and the advance of the first day of 35℃will increase the risk of high temperature forced ripening of flue-cured tobacco;According to the above changes,it is necessary to optimize the phenological period of flue-cured tobacco production on the basis of experiments.