【摘要】 单相关普查表明 ,天山西部伊犁地区的 1 0个树轮年表与该区上年 6月至当年 5月的年度降水相关显著 ,最高相关系数为 0 584 (α=0 0 0 5) .使用 5个年表序列较好地重建了伊犁地区 3 1 4a的降水长序列 ,解释方差达 75% ,经多方面验证 ,表明其具有较好的可信性 .3 1 4a来 ,伊犁地区降水经历了 4个偏湿及 4个偏干期 ,其偏湿期与北疆年降水的偏湿期 ,原苏联、我国华北与华东、祁连山敦德冰芯所揭示的偏冷期具有一定对应关系 .伊犁地区降水与中亚哈萨克斯坦东南部大范围干湿年份的对应率约为 68% .伊犁地区的降水长序列具有 1 50、 2 9、 1 7、 2 3及 60a的显著变化周期 ,且在 1 757、 1 778、 1 892和 1 92 7年发生过降水突变 ,其后两次突变与北半球或全球的温度突变年份比较一致 .相关分析指出 ,伊犁地区重建降水序列对北疆及中亚哈萨克斯坦东南部的降水变化具有较好的代表性 .更多还原

【Abstract】 Single correlation screen indicated that the correlations were significant among 10 tree-ring chronologies and precipitation from June in the last year to May in the current year, and the maximum correlation coefficient was 0.584 (α=0.005). Using 5 tree-ring chronology series, the 314 a precipitation was well reconstructed and its explain variance was 75%. It is verified that the reconstructed precipitation was more reliable. Several conclusions obtained by analyzing the precipitation sequence reconstructed are as follows: 1) In the recent 314 a, the precipitation reconstructed has 4 wet periods above its mean and 4 dry periods bellow its mean. The wet periods were corresponding to the wet periods of annual precipitation reconstructed in the Northern Xinjiang, and the cold periods in former USSR. North and East China and in the Qilian Mountains. 2) Correlation analysis shows that the precipitation series reconstructed in the Yili Prefecture is well representative of precipitation change in the Northern Xinjiang and in the Southeastern Kazakhstan. 3) The corresponding ratio of wet-dry year between the Yili Prefecture and the Southeastern Kazakhstan is about 68%. 4) The long-term precipitation series reconstructed in the Yili Prefecture has significant change periods of 150, 29, 17, 23 and 60 a, and occurred abrupt changes in 1757, 1778, 1892 and 1927. The abrupt changes in 1892 and 1927 were corresponding to the temperature abrupt changes in North Hemisphere and the globe, but the response of precipitation in the Yili Prefecture to the temperature abrupt changes in the globe was complicated. 5) In the 314 a precipitation reconstructed in the Yili Prefecture, wet year accounted for 9.6%, drought year 6.0%, partial wet year 19.7%, partial drought year 29.3%, and normal year 35.4%. The maximum precipitation (585.1 mm) occurred in 1813, which was 66.9% more than the long-term mean, and the minimum precipitation (177.3 mm) occurred in 1693, which was 49.4% less than the long-term mean. 6) It is expected that the change trend of precipitation in the Yili Prefecture is manly near or above its mean from 1996 to 2002, near or bellow its mean during 2003～2015, after that, precipitation go into a stage mainly near or above its mean.更多还原