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机构地区:[1]天津市气候中心,天津300074 [2]中国民航大学,天津300300
出 处:《安徽农业科学》2010年第10期5226-5228,共3页Journal of Anhui Agricultural Sciences
基 金:2007年北京区域气象中心科技创新基金项目(BRMCCJ200707)
摘 要:通过计算华北地区近50年的降水量、初霜日、终霜日及冬小麦各生育时期的积温等农业气象指标,对该地区冬小麦生产的气候资源变化趋势进行了分析。结果表明,近50年来,华北地区的积温增加,霜期缩短,关键季节降水总体减少,冬小麦各生育时期等日线在空间上北移,小麦返青和拔节期的变化较明显。The change trend of climatic resources for winter wheat production in north china was analyzed through calculating the agrometeorological indexes such as precipitation,the first and the late frost dates and the accumulated temperature in each growing stage of wheat in recent 50 years in this area.The results showed that the accumulated temperature in north china in recent 50 years was increased,the frost period was shortened and the precipitation in key seasons was generally decreased.The equal diurnal line in each growing stage of wheat was northward moved in space and the changes of green and jointing stages of wheat was obvious.
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