Population Structure and Regeneration Mode of Main Tree Species in the Korean Pine-Broadleaved Forest in Jiaohe, Northeast China

Based on investigation of all the trees in a 3.2 hm² plot in the Korean pine-broadleaved forest (KPBF) in Jiaohe, this paper studied the size structure of major tree species in the KPBF and analyzed the regeneration modes and mechanisms of the tree species.The results show ed that maximum size class and distribution of individuals of different species in each size class were different, and the maximum size classes of coniferous trees were generally bigger than those of broadleaved trees.The tree species in the KPBF may be classified into four types according to their size structure. The tree species in the KPBF can also be classified into four types on the bases of the fitted equations for accumulated number percentage along size class for different tree species. Based on the investigation results, we discussed the equilibrium properties of tree size structure, analyzed the regeneration modes of major tree species in the KPBF and their relationships with natural disturbance regimes and the temporal and spatial scales. Finally we discussed the effects of plot size on the results of population structures in the KPBF.