关键词: 冬小麦, 冬小麦, 抗寒性, 成活率, 半致死温度

Abstract: Air temperature change is one of the important issues of the global climate change, it has significance to ecological environment construction and protection, agricultural production and meteorological disaster prevention and reduction. The annual mean temperature and change characteristic of air temperature of each season of Ankang City were analyzed by the method of climatic trend rate, sliding average method, the M-K trend test and mutation analysis method based on the data of the daily and annual average temperature from 1951 to 2010. The results showed that: (1) the annual average air temperature of Ankang City in nearly 60 years showed an increasing trend with the climatic trend rate of 0.05℃/10 a, and it experienced three stages as“warm-cold-warm” , before the mid-1960s was warm stage, between mid-1960s to mid-1990s was cold stage and then was warm stage; (2) the decadal variability of annual average temperature showed a“gently increasesignificantly decrease-significantly increase”trend, the period of 1980s was cold stage, but the mutation was not found; (3) the average air temperature of spring, autumn and winter showed an increase trend, it was warm stage after the 1990s, and the change was obvious in winter and spring, followed by autumn, a decrease trend was showed in summer, the decrease trend was obvious after mid-1990s, which turned into cold stage; (4) the average air temperature of summer and winter in nearly 60 years had obvious mutations in 1974 and 1991, but there was no obvious mutation in spring and autumn. The temperature showed a warming trend in winter and spring and a cooling trend in summer.