共和盆地界限温度初终日和积温对气候变化的响应

利用青海省共和盆地海南州气象台1953—2010年逐日平均气温，以5 d滑动平均法确定稳定通过≥0℃、≥3℃、≥5℃、≥10℃初、终日，求算初终日间持续日数、活动积温和有效积温，分析界限温度初终日、持续日数和积温的变化，应用Pearson函数求算界限温度初终日、初终日期间持续日数、活动积温和有效积温与年平均气温的相关性并建立回归模型。结果表明:共和盆地各级界限温度初日均呈提前趋势，终日均呈推后趋势，初终日间持续日数呈增加趋势，活动积温和有效积温均表现为增大趋势；各界限温度初日与年平均气温呈负相关，终日与年平均气温呈正相关，初终日间持续日数呈正相关，活动积温和有效积温与年平均气温极显著相关；若年平均气温升高1℃，则各界限温度初日提前3～6 d，终日推迟3～4 d，各界限温度期间的持续日数延长6～10 d，活动积温增加165～190℃，有效积温增加164～183℃。

Responses of Initial/Final Date and the Accumulated Temperature Steadily above the Agricultural Threshold Temperature to Climate Change in Gonghe Basin,Qinghai Province

The data of ground-observed diurnal air temperature were used to compute the initial and final dates of ≥0℃,≥3℃,≥5℃,≥10℃ from 1953 to 2010,as well as the duration days,available accumulative temperature and active accumulative temperature between beginning dates and ending dates,respectively,by using the method of 5 days running mean in Gonghe,Qinghai Province.Furthermore,the tendency of the initial dates,final dates,the available accumulative temperature and active accumulative temperature in recent 60 years were analyzed,and a statistical model was constructed based on the analysis of correlation between these indexes to annual air temperature by the way of Pearson function.The results showed that there were obviously earlier beginning in the initial dates and later ending in the final dates appeared in all of the threshold temperatures,accompanied with this trend,it showed a significantly increasing trend in the duration days,the available accumulative temperature and the active accumulative temperature.It was found that a negative correlation of annual air temperature related to initial dates ≥0℃,≥3℃,≥5℃,≥10℃,and a positive correlation with final dates and the duration days,especially significant at 0.001 level with available accumulative temperature and active accumulative temperature.A simulated test was run on basis of a hypothesis of 1℃ increment of air temperature in the future,it indicated that the initial dates should begin 3~6 d earlier,final dates should end 3~4 d later,the duration days should extend 6~10 d,and the available accumulative temperature and active accumulative temperature should increase 165~190℃ and 164~183℃,respectively.