The response of spring temperature, last frost and winter wheat growth to climate warming was analyzed based on meteorological data and fields experiment data in Xifeng station Gansu province.The results showed that the average spring temperature increased at the rate of 1.2℃/10y, average spring minimum temperature increased at the rate of 1.1℃/10y, and extreme minimum temperature in May increased at the rate of 1.2℃/10y from 1981.The extreme minimum temperature in April has changed in fluctuation since 1997, the extreme minimum occurred in 2001 and 2006.The date of last frost advanced at the rate of 3.2d/10y, and surface minimum temperature changed in fluctuation.The jointing date of winter wheat advanced at the rate of 4.5d/10y from 1981 ( P ＜ 0.01 ) and more early from 1997.The jointing date advancing rate of winter wheat was greater than that of last frost, which indicated that winter wheat could faced more freezing risk during jointing to booting stage in spring.%利用位于黄土高原中部的甘肃西峰试验田资料和当地平行气象观测资料,分析了春季气温、终霜冻和冬小麦生长发育对气候变暖的响应特征.结果表明:1981年以来,春季平均气温和平均最低气温分别以1.2℃/10a和1.1 ℃/10a的速率升高,5月的极端最低气温以1.20C/10a的速率升高;1997年以来4月极端最低气温波动幅度增大,在气候变暖大背景下2001年和2006年出现了最小值,属于反常年份,冻害严重;终霜日期提前的气候趋势比较明显,速率为3.2d/10a,终霜日地面最低温度表现为波动变化,个别年份出现反常的重霜冻灾害;终霜冻过程的持续日数表现出阶段性增加规律,地面最低温度负积温在反常年份2005-2006年有增强变化;1981年以来冬小麦拔节期以4.5d/10a的速率极显著提前(P<0.01),1997年以来提前趋势更加明显,1997-2008年平均拔节期比1981-1996年提前9d.气候持续变暖,冬小麦拔节期提前的速率大于终霜日提前的速率,表明冬小麦春季拔节-孕穗期遭受终霜冻危害的气候风险在增大.
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