Objective The study expored the species abundance distribution pattern and its driving process, as well as the relationship between species abundance distribution and trait distribution, so as to provide theoretical support for strategies formulation of local forest management and restoration strategies.

Method The study objects were three forest plots of 5.2 ha (secondary Populus davidiana-Betula platyphylla mixed forest, secondary coniferous and broadleaved mixed forest, primary Pinus koraiensis-Tilia amurensis mixed forest) and one forest plot of 5 ha (primary broadleaved-Pinus koraiensis mixed forest). Six functional traits, including leaf area, specific leaf area, leaf thickness, max. tree height, leaf nitrogen concentration, and leaf phosphorus concentration, were measured to analyze the distribution patterns of species abundance and functional traits in the sample plot, as well as their relationship.

Result Although the types of the models that had passed statistical tests varied in different stands, all optimal models were statistical models. In the distribution patterns of traits, the max. tree height, specific leaf area, and leaf phosphorus concentration of the 4 sample plots showed a normal distribution. However, the model of species distribution converted from the functional traits distribution showed that although some models had passed statistical tests, it could not fit the real species abundance distribution well.

Conclusion Random process is not the main mechanism driving the formation of species diversity in Changbai Mountain. Instead, competition has a significant effect on species diversity, which determines the change of community species composition during forest succession. There is a correlation between functional trait distribution and species abundance distribution, but community-level trait distribution cannot be applied to infer species abundance distribution directly.