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近百年来全球气候正经历一次以变暖为主要特征的显著变化,但不同的生态系统对全球变暖如何响应是一个值得深入研究的问题.本研究选取阿尼玛卿山区三个坡面(YYCHBSHHB)以及林线处的祁连圆柏.利用树轮生态学方法来研究树木更新以及林线动态与气候变化之间的关系.通过对三个坡面以及各坡面的上限圆柏的年龄结构以及林线动态分析发现:自14世纪末期开始,YYC坡面树木便处于不断的更新之中:15世纪末期以来HBs坡面树木开始更新;HHB坡面从18世纪末期开始才有树木更新:YYC坡面树木更新出现了1550-1650年和1800--1900年两个高峰期:HBS坡面和HHB坡面的树木更新只有1800--1900年一个高峰期;三个坡面上限圆柏的更新都只有一个高峰期:1800-1900年.近百年没有显著的更新是由于没有采集小树.因此本文没有讨论近百年的树木更新.树木平均年龄随着海拔的升高而不断减小,表明近200年来树木的更新和林线向高海拔迁移在本研究区体现很明显.树木年龄更新变化通过与重建的中国温度(Yangetal,2002)和北半球温度(D'Arrigoetal,2006)对比发现,阿尼玛卿山树木更新变化与升温关系密切.这表明温度可能是研究区树木更新的一个决定因素. “,”Alpine forests are particularly prone to temperature change and warrant special consideration. The responses of treeline environments to climate change were examined in the Anyemaqen Mountains, northeastern Tibetan Plateau, employing age structure and average age of the trees from three Ju, niperus przewalskii Kom (Qilian juniper) slopes (YYC, HBS, and HHB). The age structure analysis results showed that the J. przewalskii forest growing appeared at the end of 14th century on YYC slope, at the end of 15~h century on HBS slope and at the end of 18th century on HHB slope. The appearance of trees at the upper treeline limit dates to different periods. There was one recruitment peak during the period 1800-- 1900 on three slopes and upper limit sites. Tree regeneration and treeline dynamics coincide well with air temperature. The average age of trees declined with increasing altitude on the YYC and HHB slopes, which demonstrated that trees at higher elevations have established later than lower elevations and the treeline advancing upslope in research area. The low limit sites beside the road on the HBS slope, sothere was human disturbance on this slope, which appearance the different average age trend from other two sides. The results of this work indicate that higher air temperatures will increase tree numbers along treeline in this mountainous region of China that likely will alter the forest age structure and forest-climate interactions and feedbacks of the treeline ecosystem in the future. What is more, human disturbance was also mainly reason which affected the tree ~ermination and tree line dynamics.