高山林线对于气候变化的影响非常敏感。气候变化首先从个体的水平影响林线的内部结构 ,然后才影响到作为整体的林线的推移 ,因此研究乔木个体生理活动与气候条件之间的关系 ,对于研究高山林线对气候变化的响应具有重要意义。本文通过对位于中国东部暖温带的五台山、关帝山、太白山森林上限附近白杆 (Piceameyeri)、华北落叶松 (Larixprincipis-ruprechtii)和太白红杉 (L .chinensis)生理活动与环境因子的野外测定 ,分析了光合作用与环境因子之间的关系 ,得出以下初步结论 :(1)研究区内林线乔木的光合作用不存在单一的限制因子 ;(2 )有关研究表明 ,光照与温度共同作用于高山林线乔木的光合作用 ,在光照较低的情况下 ,温度成为光合作用的限制因子 ,本研究进一步证实了这一现象 ;(3)树线、林缘、郁闭林内三种不同生境条件下乔木光合作用的对比表明 ,林缘的生境条件最适合植物光合作用。虽然林缘的湿度条件中等 ,但良好的光照和温度条件对光合作用有促进作用 Alpine timberline is very sensitive to the impact of climate change. Climate change firstly affects the internal structure of the forest line from the individual level and then affects the forest line as a whole. Therefore, the relationship between individual physical activities and climatic conditions is studied to study the response of the mountain forest line to climate change It is of great significance. In this paper, the field activities of Piceameyeri, Larix principis-ruprechtii and L. chinensis near the forest upper limit of Wutai Mountain, Guandi Mountain and Taibai Mountain, and the environmental factors in the warm temperate zone of eastern China The relationships between photosynthesis and environmental factors were determined and analyzed. The following conclusions were drawn: (1) there is no single limiting factor for the photosynthesis of tree arbors in the study area; (2) The research shows that the combination of light and temperature The photosynthesis of trees in the alpine forest line showed that the temperature was the limiting factor of photosynthesis in the low light conditions. This study further confirmed this phenomenon. (3) Three different species in the tree line, forest margin and canopy cover The comparison of photosynthesis of trees under habitat conditions shows that the habitat conditions of forest margin are the most suitable for plant photosynthesis. Although the forest edge of the humidity conditions are moderate, but good light and temperature conditions have a role in promoting photosynthesis