Abstract:

According to the climatic data in summer-maize growing season and the corresponding meteorological observation data at Qihe County of Shandong Province from June to September in 2016, the temperature variation characteristics in the summer-maize field under different sky conditions were analyzed. The relationship between the minimum, maximum temperatures and meteorological elements at Qihe observation station was studied using the method of correlation and multiple linear regression analysis, and the minimum and maximum temperatures prediction equations were established. The results are as follows: (1) The temperature in the summer-maize field had obvious diurnal variation, which was most obvious on sunny days and gentlest on cloudy days. Air temperature was lowest during 05:00-06:00 and highest at 15:00. Maximum absolute value of temperature difference between that of summer-maize field and meteorological observation was 2.1 ℃ and appeared during 14:00-15:00. (2) Correlation coefficients between the minimum and maximum temperatures in summer-maize field and all forecast factors varied with the sky conditions. The minimum temperature, the maximum temperature and average temperature of the same day and the day before at meteorological observation station were the main influencing factors. Correlation coefficients were higher between the minimum temperature in summer-maize field and that at observation station on the same day which ranged from 0.956 to 0.994, and correlation coefficients between the maximum temperature in summer-maize field and that at observation station on the same day ranged from 0.825 to 0.981. (3) Forecast equations were established and they passed the test of significance. Fitting degree of the minimum and maximum temperatures forecast equations was higher. The prediction effect showed that the average relative error of the minimum temperature forecast equation at late jointing and maturity stages on overcast days was 0.4%, the average absolute error and root mean square error was 0.1 ℃, respectively.

Key words: summer-maize, farmland temperature, variation characteristics, minimum and maximum temperatures forecast

摘要：

根据2016年6—9月夏玉米生长季的气候资料和齐河国家气象观测站的同期观测资料，分析不同天空状况下农田的气温变化特征，利用相关和多元线性回归方法，研究农田最低、最高气温与观测站各要素的关系并建立高低温预报方程。结果表明：（1）农田温度有明显日变化，晴天最为明显，阴天最为平缓， 05:00—06:00（北京时，下同）气温最低,15:00气温最高，农田与观测站温差绝对值晴天最大，14:00—15:00差值绝对值最大达2.1 ℃；（2）农田气温与各预报要素的相关程度受天空状况影响，主要影响因子为观测站当天和前一天最低、最高及平均气温等，农田最低气温与观测站当天最低气温相关系数为0.956～0.994，农田最高气温与观测站当天最高气温相关系数为0.825～0.981；（3）构建的预报方程通过了显著性检验，最低、最高气温预报方程的拟合程度均较高，夏玉米拔节后期—成熟期阴天时最低气温预报效果最好，平均相对误差为0.4%，平均绝对误差和均方根误差均为0.1 ℃。

关键词: 夏玉米, 农田气温, 变化特征, 高低温预报