北方旱作农区农业气候资源时空变化特征

Spatiotemporal changing characteristics of agricultural climate resources in northern dry crops farming area

利用北方旱作农区317个气象台站1961—2010年地面气象观测资料,分析和比较了1961—1990年(时段Ⅰ)和1991—2010年(时段Ⅱ)农业气候资源变化特征。结果表明:全区日照时数总体呈降低趋势,时段Ⅱ较时段Ⅰ平均减少了92.9h;研究区域近50年年降水量变化呈现西部增加东部减少的特征;与时段Ⅰ相比,时段Ⅱ研究区域年均气温增加了0.97℃,高于全国平均水平,日平均气温稳定通过0℃、10℃的持续日数普遍呈增加趋势,喜凉作物生长期内≥0℃积温和喜温作物生长期内≥10℃积温分别平均增加198.6℃·d和197.3℃·d;研究期间全区气候变化西部地区总体呈暖湿趋势,东部地区总体呈暖干趋势。

Based on the meteorological observed data from 317 climate stations during 1961 to 2010 in northern dry crops farming area ,analyzed and compared the change characteristics of agricultural climate resources in 1961 to 1990 （periodⅠ） and 1991 to 2010 （period Ⅱ） .The resuls showed that ：The sunshine hours in total region presented a de-creasing trend on the whole ,compared with periodⅠ ,the average has been reduced 92 .9h in period Ⅱ .The precipita-tion in whole region showed an increasing trend in west part and a decreasing trend in east part during recent 50 years . As compared with periodⅠ ,the mean annual temperature has been increased 0 .97℃ in period Ⅱ ,which was higher than the national average level .Besides ,duration of daily mean temperature steadily passed 0℃ and 10℃ showed a gen-erally increasing trend ,the ≥0℃ active accumulated temperature in the growth periods of chimonophilous crops and the≥10℃ active accumulated temperature in the growth periods of thermophilic crops increased averagely by 198 .6℃ and 197 .3℃ ,respectively .The climate change in whole research region ,presented a warm and wet tendency in the west , but warm and dry tendency in the east .