关键词: 冬小麦, 气候变化, 灌浆期, 干热风

Abstract: According to the meteorological occupation standard for dryhot wind hazard of winter wheat, daily meteorological element data from 1961 to 2007 in later growth stage of winter wheat at 118 stations in Henan province was taking used for analyzing the variation of range and frequency, et al for high temperature and low humid type of dryhot wind hazard. The results showed that： in the recent 47 years, the wind speed at 14:00, which was closely relate to the hazard declined conspicuously, and a climatic mutation point was found near 1983, while other meteorological elements varied insignificantly. In view of the overall weakening trend of the hazard, the range and days that different grades of the hazard occurred was increasing after 1990s, especially the increasing speed of ratio of stations that light hazard occurred reached to 2.01%,and the days that the hazard happened reached to 0.07. According to running mean statistic，the frequency of all grades of dryhot wind hazard was decreasing, however, it showed a trend of accelerating in the late 30 years.

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