中文摘要：

本文基于陇东地区15个气象站点1971年-2010年的逐日气温和地温资料,采用相关分析、气候倾向率、MK突变检验法,结合GIS空间分析技术,对各站逐年的初、终霜日、无霜期及≥0℃、≥10℃和〈0℃积温与持续日数等进行定量化分析,并阐述其时空变化特征及相互关系。结果表明：陇东地区初霜日和无霜期分别与纬度和海拔呈负相关,与经度呈正相关,终霜日则与纬度和海拔呈正相关,与经度呈负相关;20世纪70年代和80年代初霜日偏早,终霜日偏晚,无霜期较短,自90年代以来呈反向变化;大部分地区初霜日后推,终霜日提前,无霜期延长,主要集中在中南部的镇原、崇信等地;初霜日和无霜期的突变年分别在1986年、1987年和1984年,终霜日无明显突变年。本区积温呈显著上升趋势,积温年均最大值与年均最晚初霜日、最早终霜日和最长无霜期都位于陇东南部地区;积温年均最小值与年均最早初霜日、最晚终霜日和最短无霜期则分布于西部和北部地区。

英文摘要：

Using daily air temperature and ground temperature data for 15 meteorological stations in eastern Gansu Province from 1971-2010 we conducted correlation analyses,determined the rate of climate tendency and moving t-test,and applied GIS spatial analysis techniques and mathematical statistics theory.Agro-climatic resources of the first frost date,the last frost date,the frost-free period and ≥0℃,≥10℃,and 0℃ accumulated temperature and number of days were quantitatively analyzed.Variations in temporal and spatial characteristics and the relationship between frost days and accumulated temperature were illuminated.Our goals were to fully understand and use the local agro-climatic resources,and guide the adjustment of local cropping systems,agricultural production and activities.The results showed that the first frost date and frost-free period were negatively correlated with elevation and latitude,and positively correlated with longitude.The last frost date was positively correlated with latitude and altitude and negatively with longitude.The first frost date was earlier,the last frost date was late and the frost-free period was shorter in western and northern parts;this pattern was reversed in the east and south.The first frost day was earlier,the last frost day was late and the frost-free period was shorter in the 1970s and 1980s,but the changes were reversed in the 1990s.The first frost date was pushed back,the last frost date advanced and the frost-free period extended in most parts,especially in the south-central towns of Zhenyuan and Chongxin.A significant upward trend of accumulated temperature was shown in this region：higher values are located in the central region and lower values in the western and northern region.The average annual maximum of accumulated temperature,the average annual latest first frost date,the earliest last frost date and the longest frost-free period were all located in southern region（Jingchuan and Chongxin）,while the average annual minimum accumulated temperature,averag