长白山原始林红松径向生长及林分碳汇潜力

长白山地处温带针阔混交林的中心地带,其植物生长对气候变化反映较为敏感。运用树木年代学的基本原理与方法,以该区保存完好的地带性顶级群落阔叶红松林为研究对象,探讨了红松(Pinus koraiensis)径向生长对气候变化的响应,以期揭示全球气候变化对阔叶红松林及红松树木生长的影响。以长白山自然保护区北坡为研究地点,建立红松树轮年表,计算年均生物量生长量,与逐月各气候因子进行相关和响应函数分析,以期揭示红松径向生长与气候变化的关系。同时利用多元逐步回归分析方法分别建立了红松树轮指数、年均生物量生长量与主要气候因子的模拟回归方程。主要结论如下:(1)长白山红松年表特征分析表明其生长对气候变化敏感,适用于进行树轮气候学分析;(2)红松径向生长受当年生长季前期温度影响较大;(3)温度是限制红松径向生长的主要因子,气候变暖将促进红松的径向生长;(4)目前林分单位面积地上生物量为310.88t/hm~2,单位面积林分生物量生长量约为5.077t hm~(-2)a~(-1),即每公顷每年固碳约2.539t,表明该地区老龄阔叶红松林仍具有较强的固碳能力。

Radial growth of Pinus koraiensis and carbon sequastration potential of the old growth forest in Changbai Mountain, Northeast China

The vegetation of Changbai Mountain, located in the heartland of temperate coniferous and broad-leaved mixed forest, is subject to climate change. Using the basic principles and methods of dendrochronology, and Pinus koraiensis growing on northern slopes of Changbai Mountain as objects, objectives of this work were to: (1) study the variation of tree-ring width of P. koraiensis to better understand the response of the forest ecosystem to climate change; (2) establish chronologies of P. koraiensis, correlation, and response functions with monthly climatic factors, and calculate the average biomass growth in successive years; and (3) establish regression equations for tree-ring index and the average annual biomass increment of P. koraiensis. The main conclusions are: (1) Growth of P. koraiensis was sensitive to climatic factors according to the analysis of chronology, which is suitable for dendroclimatological study. (2) Radial growth of P. koraiensis was mainly affected by the temperature of the early growing season. Radial growth was more strongly correlated to temperature than to precipitation. (3) Temperature was the main factor limiting growth, which indicated that climate warming might accelerate tree growth. (4) At present, the aboveground biomass of P. koraiensis growing on northern slopes of Changbai Mountain is 310.88 t ha^-1, with an increasing rate of 5.077 t hm^-2 a^-1 or 2.539 t carbon, indicating that the old-growth forest of P. koraiensis in the region still has a strong potential for carbon sequestration."