中文摘要：

根据川西卧龙地区林线位置岷江冷杉（Abies faxoniana）的年轮宽度资料,分析了该地区树木年轮宽度与气候要素的关系,并重建了该地区1850年以来夏季（6-8月份）温度的变化历史。结果表明：川西卧龙地区在过去159年来的温度变化上,最为明显的特征是20世纪40年代以来的显著变暖趋势,而在20世纪40年代以前的温度明显偏低,主要的低温时期在1850-1870年和1890-1930年。该温度序列的冷暖期与附近地区的冰芯、冰川进退资料,以及对于夏季温度响应敏感的树轮年表都有着较好的对应关系,这表明重建序列记录了可靠的区域尺度的温度信号。对重建温度序列的小波分析表明,较为明显的有2-8年和10-16年的周期,而这些周期可能与厄尔尼诺-南方涛动气候系统和太阳活动周期有一定的关系。

英文摘要：

Aims Improved understanding of tree growth responses to climate is needed to model and predict forest ecosystem responses to current and future climatic variability. Coniferous forests in Wolong National Natural Reserve occupy broad elevational ranges with varied geology and topography and thus have great potential for dendrocli-matological studies. However,little is known about the growth-climate relationships in this region compared with the nearby Tibetan Plateau. Our objective was to determine the main climate responses in diameter growth and examine the regional climate variability within this ecological complex area. Methods We used standardized dendroecological methods to study the effects of climatic variability on radial growth of a subalpine conifer,Abies faxoniana,which is the dominant and economically most important tree species in this region. We sampled 58 stands of A. faxoniana in a treeline site （3 450 m） and extracted increment cores for radial growth analyses. Several statistics were used to identify common patterns of interannual growth variability,and correlation and regression analyses were used to identify climatic factors associated with that variability. Important findings The main limiting factor for tree growth was temperature in summer （June to August）,followed by temperature in early spring （March）,relative humidity from June to September of the current year and precipitation in October of the prior year. The summer （June to August） temperature reconstruction,spanning A.D. 1850–2008,was verified with independent data and accounted for 28.8% of the actual temperature variance during the period in common period （1955–2008）. The most obvious characteristic of the reconstructed temperature was a significant warming trend after the 1940s. Before the 1940s,the climate of this region was consistent cold,with cold intervals in the 1850s–1870s and the 1890s–1930s. Because the low-frequency variation of the reconstruction agreed with previously published tree-ring pro