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通过对比天山东段森林上限3个树轮宽度标准化年表的多项年表特征,发现太阳沟年表包含的气候信息较多.经相关普查计算表明,太阳沟年表与巴里坤气象站上年7月到当年6月的月平均相对湿度相关最为显著,相关系数为0.591,显著水平超过0.00001.利用太阳沟标准化树轮宽度年表序列重建出天山东段443年来该时段月平均相对湿度,解释方差达到34.9%.近443年相对湿度特征分析指出:天山东段的月平均相对湿度经历了6个偏湿阶段和5个偏干阶段:天山东段上年7月到当年6月的月平均相对湿度具有2-4年的变化准周期;在1592年、1643年、1704年、1761年、1792年、1855年、1884年、1926年、1951年及1985年前后发生过突变. “,”Tree ring played an important role in the studying of global climatic change. There have developed thorough work for searching the climatic potential of tree ring in most area of the world. In this paper, the tree-ring cores of Larix sibirica Ledeb. collected from three sites on the upper limit of the forest in eastern Tianshan Mountains. Comparing with some parameters of the three tree-ring width standardized chronologies, the results indicated that Taiyanggou chronology contented more climatic information. Single correlation calculation indicated that the correlation coefficient was 0. 591 ( significant is much greater than the 99.9 percent level) between the tree-ring index of Taiyanggou and monthly mean relative humidity from last July to June of Barkol meteorological station. Thus, the result has distinct physiological significance. By means of stepwise regression method, using Taiyanggou standardized tree-ring chronology series, the long-term sequence of recent 443 years' monthly mean relative humidity was reconstructed from last July to June, with an explained variance of 34.9%. It was verified that the reconstruct relative humidity was reliable by leave-one-out. The reconstructed monthly mean relative humidity index had stable periods of 2 -4 year and abrupt change in 1592, 1643, 1704, 1761, 1792,1855, 1884, 1926, 1951 and 1985. In this area, there were 6 and 5 remarkable moist and dry periods.