黄淮麦区冬小麦拔节后霜冻温度出现规律研究

Occurrence of frost temperature in Huanghuai wheat production zone after winter wheat elongation

用37个农业气象观测站20年逐日最低气温资料,统计出现<0℃和<-1.4℃的累积频率,它们随时间的变化可用指数方程来描述。分析了表征方程特点的参数b、<0℃和<-1.4℃基本终止日期的地区分布规律。根据遭遇霜冻温度的累积频率和拔节期,找出霜冻的可能多发区,并讨论了b值在制定防御霜冻对策中的应用。

Data on minimum day air temperature after wheat elongation was collected over a period of 20 years from 37 agro-meteorological observation stations in Huanghuai wheat production zone and the environs. Using the data, cumulative occurrence probability of temperatures lower than 0℃ （G〈0℃）and - 1.4℃ （G〈- 1.4℃ ） were statistically analyzed. Results indicate variations in G 〈0℃ and G 〈 - 1.4℃ with time are well described by exponential functions. Variations in area of b value, function characteristic parameter, and approximate termination dates of air temperatures lower than 0℃ and -1.4℃ were also analyzed. Based on the occurrence probability of low temperatures and spatio-temporal variations in wheat elongation time, potential areas of frequent frost occurrence were delineated. Finally, application of b value in frost prevention strategies was discussed.