[Seedlings regenerative dynamics of dominant trees in a secondary forest in montane region of eastern Liaoning Province, China].

To reveal the seedlings dynamics of dominant trees and their response to canopy changes (as indicated by changes in leaf area index), we analyzed the seedlings dynamics of dominant trees and canopy structure during forest regeneration based on three-year (2014 to 2016) censuses and hemispherical photography in a 4 hm ² forest dynamics monitoring plot. The results showed that canopy LAI first decreased and then increased during the survey period, with significant interannual difference. The seedlings of 12 dominant tree species showed notable response to the change of canopy structure, with the response varying among different tree species. The relative abundance or frequency of seedlings for neutral tree species generally increased with the decreases of canopy LAI. The relative abundance or frequency of seedlings of light-demanding tree species generally decreased with the increases of canopy LAI. In multi-response permutation procedures by analyzing the numeric composition and distribution of dominant tree seedlings, there was significant difference among the three censuses. Such interannual difference gradually decreased from 2014 to 2016. Significant change occurred in the indicator species of dominant tree seedlings, reflecting their responses to the changes of canopy structure.