Study On Regeneration Niche Based On Ecostate-ecorole Theory

Based on the niche ecostate-ecorole theory proposed by Chunquan Zhu, we improve the model of regeneration niche, regarding the niche of the arbor tree and the sapling as the ecostate and the ecorole of the regeneration niche. Through the investigate on the gap regeneration of the Changbai Korean pine broad-leaved mixed forest, the quantitative characteristics of regenerated tree species in the gaps were analyzed, and the breadth and the overlap of the regeneration niche were calculated in this paper. The result shows that the improved model dose not only ensure the mathematics logistic coherence, but also increase the ecological explain meaning, and advance the precision of the regeneration niche metrics.Studies show that gaps significantly affect forest architecture and environment, influence growth and reproduction of plants, and affect animal distributions. Gaps also help maintain tree diversity through the density effect and some niche partitioning. The sequence of the regeneration niche is similar to the species' importance value in nongap areas, which can explain the relative stabilization of the community structure. The species holding wide regeneration niche will adapt to the environment and have higher importance value rather than those holding narrow regeneration niche.The death of an adult tree creates a forest gap in which light and soil resources are available for saplings or colonizing seedlings. Studies show that light-demanding pioneers occur preferentially within gaps, holding wider regeneration niche, Tilia amurensis, Fraxinus mandshurica, Maachia amurensis, and Acer trifiorum rather adapt to the environment in the earliest stages of succession, which is demonstrated by the improved model rather than Shannon-Wiener index exactly.With the increase of the gap age, the pioneer community gradually grades into a community dominated by climax of Acer mono, Ulmus japonica, phellodendron amurense, Acer mandshurica. The results of the improved model and Shannon-Wiener index appear similar, because the succession is prone to be end.