Study on understanding of disturbance regime and mechanisms of tree species coexistence for sub-boreal and sub-alpine evergreen coniferous forests.

为了了解亚寒带和亚高山森林的物种共存情况，利用半球面照片估算的天空因子数据集，采用局部加权回归平滑法，建立了量化单株树木光照条件的新方法。比较了两种菊科植物茎粗的生长率。亚高山森林随间接天空因子的增加而增加。另一方面，光照条件对亚寒武带林下植物茎部生长模式的影响小于亚高山林下植物。

To understand species coexistence in sub-boreal and sub-alpine forests, the new methods quantifying light condition of each individual tree were developed by a locally weightedregression smoothing method with the data set of the sky factors, which were estimatedusing hemispherical photographs. The growth rates of the stem diameter for the twoAbiesspp. increased with the indirect sky factor in the sub-alpine forests. On the other hand, the effect of the light conditions on the stem growth patterns of the understory in asub-boreal forest was smaller than those for the species in the sub-alpine forests.