【摘要】 利用张掖市6个气象观测站1961-2010年实测气温资料,运用5 d滑动平均、气候倾向率、M ann-Kendall检验等方法,对农耕期初日、终日、持续日数及≥0℃积温的分布特征、年际和年代际演变规律及突变特点进行分析,结果表明:张掖市农耕期初日随海拔高度的升高推迟,终日则相反,农耕期日数自西北部向东南缩短,积温南北差异显著;近50 a初日提早,终日推迟,持续日数延长,积温增加趋势明显;20世纪70-80年代前期各地表现出农耕期初日推迟,终日提前,持续日数较短,≥0℃积温偏少的特点;20世纪90年代以来,终日延迟程度大于初日提前程度,积温增加显著,尤其2001-2010年增幅为50 a最大;山前绿洲及荒漠绿洲农耕期终日、持续日数及积温分别在1995/1997年、1982/1990年、1996/1999年发生了突变;农耕期热量资源增加,对作物种植结构的调整、生育进程的加快及产量均产生一定影响.更多还原

【Abstract】 Based on the daily air temperature data from six counties of Zhangye Prefecture during l961- 2010,the annual and decadal variations and their abrupt characteristics of beginning and the ending dates of farming period,farming days,as well as cumulated temperature higher than 0 ℃ in Zhangye Prefecture were analyzed by using the methods of five-day sliding average,climatic tendency rate,Mann-Kendall test and mutation test. The results showthat,spatially,during the 50 years,the beginning date of farming period delayed with the increase of latitude in the central Hexi Corridor,but the ending date presented reverse tendency. The farming days decreased from southeast to northwest,and the cumulated temperature higher than 0 ℃ was outstandingly different in the south and the north of Zhangye Prefecture. Temporally,the beginning date of farming period was in advance and the ending date prolonged obviously,as well as the farming days extended,cumulated temperature higher than 0 ℃ increased from 1961 to 2010 in Zhangye Prefecture. From the1970 s to the early 1980 s,the beginning date of farming period postponed and the ending date was in advance,the cumulated temperature higher than 0 ℃ and farming days decreased in the most weather stations in the central Hexi Corridor. In the1990 s,it could be found that the ending date extended obviously,so farming days also extended,the cumulated temperature higher than 0 ℃ increased evidently. Especially in the 2000 s,the cumulated temperature higher than0 ℃ increased to the maximum during the last 50 years. The ending date of farming period,farming days and cumulated temperature higher than 0 ℃ in oases in front of mountains and desert oases had abruptly changed in1995 / 1997,1982 /1990 and 1996 /1999,respectively. The increase of heat resources in farming period had some influence on the adjustment of cropping structure and cropping production in Zhangye Prefecture.更多还原