新疆阿尔泰山森林上树线树轮宽度的气候响应

利用阿尔泰山南坡森林上树线西伯利亚落叶松(Larix sibirica)树芯样本，建立了4个采样点的树轮宽度年表。树轮标准化年表与气候的相关分析结果表明，位于阿尔泰山中部的塔尔阿沙（TEA）年表与其东南端的巴腊朔克萨依（BLS）年表之间的相关系数最大（R=0.411，P<0.01），4个树轮年表中高频变化的同步性要强于低频变化。阿尔泰山森林上树线树轮宽度年表的气候响应显示，位于阿尔泰山脉西北端的阿库里年表（AKL）树轮生长的主要气候限制因子为气温；位于中部的TEA年表和吐孜巴依（TZB）年表影响其树轮宽度的主要气候因子是降水，气温也有一定的影响；位于东南端的BLS年表的主要气候限制因子为降水。随着树轮采样点沿阿尔泰山体自西北至东南，气温变化对森林上树线树木年轮宽度生长的影响逐渐减弱，而降水的作用则逐渐增强。

Climate Response of Tree Ring Width at Upper Treelinein the Altay Mountains,Xinjiang

In this study 246 tree cores were obtained from 109 Larix sibirica trees at four sites (named as AKL, TEA, TZB and BLS) at the upper treeline in the Altay Mountains, northwest China. The correlation coefficients between the tree ring width chronologies and climate signals revealed that the correlation coefficient between the BLS and TEA chronologies was the highest (R=0.411, P<0.01). The synchronization of the high frequency domain was higher than that of the low frequency domain in the four standardized tree ring width chronologies. The climate response of the tree ring width chronologies from the upper treeline in the Altay Mountains revealed that the main factor affecting the growth of tree rings from the AKL chronology in the northwest Altay Mountain was temperature; that in the TEA and TZB chronologies from the central Altay Mountain was precipitation, and then temperature; and that in the BLS chronology from the southeast Altay Mountain was precipitation. From the northwest to the southeast of the Altay Mountains, the effect of temperature on the growth of tree rings at the upper treeline was gradually decreased, but that of precipitation was gradually increased.