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与传统方法相比,利用树木年轮学方法研究树线过渡区树木生长温度敏感性高低的问题更注重比较树木个体间的生长情况,从各个树轮序列间的生长一致性程度和树轮序列对气候因素(气温、降水)的响应一致性程度可探讨树线过渡区树木生长的温度敏感性。为了认识高山树线过渡区内树木生长的温度敏感性问题,选择西藏昌都地区八宿县的一条川西云杉树线过渡区为研究对象,比较了过渡区内树木个体间的生长一致性,分析了树木生长与气候因素的相关性及其在个体间的异同。结果显示:树线过渡区内树轮生长在个体间的一致性较低,树轮生长与气温的关系在树木个体间的一致性也较低,而树轮生长与当年4–9月降水的关系相对较强。西藏八宿树线过渡区属于干旱区,相对于气温而言,降水对树木生长的影响更大。此外,小生境的异质性及干扰事件的发生也有可能降低树木对温度的敏感性。在全球变暖及极端气候事件增加的背景下,树木生长的温度敏感性被高估可能会导致对树线过渡区位置及树线过渡区内群落生产力等的预测产生偏差,这一问题应该在区域生态模拟研究和相关林业经营与管理上得到重视。
Compared with the traditional method, the method of using Tree-ring method to study the temperature sensitivity of tree growth in tree-line transitional area pays more attention to comparing the growth of trees among individual trees. From the degree of growth consistency and tree-ring sequence The temperature response to climatic factors (temperature and precipitation) can be used to investigate the temperature sensitivity of tree growth in the tree line transitional zone. In order to understand the temperature sensitivity of tree growth in the transitional zone of alpine tree line, a transitional zone of tree-spruce tree line in Baxu County, Qamdo Prefecture, Tibet Autonomous Region was chosen as the research object. The growth consistency of individuals in the transitional zone was compared and analyzed The relationship between tree growth and climatic factors and their similarities and differences among individuals. The results showed that the tree-ring growth in the tree-line transitional area was low in consistency among individuals, and the relationship between tree-ring growth and air temperature was also low among tree individuals. However, the tree-ring growth was different from that in April-September Relatively strong relationship. The transition zone between the Bazu-Shu line in Tibet belongs to the arid zone, and the precipitation has a greater impact on the growth of trees than the temperature. In addition, the heterogeneity of niche and the occurrence of interference events may also reduce the tree’s sensitivity to temperature. In the context of increased global warming and extreme weather events, the overestimation of the temperature sensitivity of tree growth may lead to deviations from the projections of the location of tree line transitions and the productivity of communities within the tree-line transition zone, Regional ecological modeling research and related forestry management and management attention.