Abstract: Elucidating species interaction is a core issue of ecological research. The interaction among different tree species is a key factor affecting forest community assembly. The neighborhood effect is a prominent manifestation of the interaction among tree species. As an quantiative index of the neighborhood effect, neighborhood density affects the growth and survival of individual trees within a certain range, and such effect varies among different tree species. In this study, based on data of two investigations in a 25hm² broadleaf Korean pine forest dynamic monitoring plot, we explored the role of tree species interaction in influencing community dynamics by analyzing its impacts on tree growth and survival. We found that the neighborhood density had a stronger effect on tree growth than tree survival in the broadleaved Korean pine forest, with primarily negative effect. There was a significant negative correlation between the growth and the neighborhood density ofAcer mandshuricum, Acer mono, Prunus padus, Corylus mandshurica,andSyringa reticulata. By dividing the neighborhood composition into conspecific and heterospecific neighbors, we found a significant correlation between tree growth and densities of both neighborhood types, and that the correlation with the heterospecific neighborhood density was mainly negative. There was a significant negative correlation between tree survival and conspecific neighborhood density, but a weak correlation between tree survival and heterospecific neighborhood density. The negative effect of the conspecific neighborhood density was mainly concentrated in Acer mono, Acer pseudo sieboldianum, Tilia amurensis, and Acer barbinerve. In conclusion, species interaction is an important factor affecting tree growth and survival in Changbai Mountain broadleaved Korean pine forest, with species-specific direction of interaction. Our results uncovered the effects of species interaction on tree growth and survival in the broadleaved Korean pine forest, which could facilitate biodiversity conservation in temperate forests.

Key words: mixed broadleaf Korean pine forest, Changbai Mountain, species coexistence, interaction, growth and survival.