亚热带常绿阔叶林群落重建过程中林下物种组成及系统发育多样性分析OA

[Objective]This study compared species composition and phylogenetic diversity between naturally restored(30-year)secondary forests and primary forests in Huangyanshan.It analyzed differences in understory community reassembly mechanisms.[Method]The investigation employed a plot-based survey method collecting tree,shrub,and herb community data.Calculations determined species diversity indices and phylogenetic diversity indices.Analysis assessed trends in these indices and the influence of soil factors.This approach revealed ecological 82 species,while natural forests had 48 families,71 genera,and 96 species.Natural forests showed significantly higher tree layer species evenness than secondary forests(P<0.05).Shrub and herb layers exhibited significant differences in phylogenetic diversity indices between forest types(P<0.01).Tree and shrub layers displayed clustered phylogenetic structures(nearest relatedness index(NRI)>0,nearest taxon index(NTI)>0)in both forests.Herb layers generally maintained over dispersed structures(NRI<0,NTI<0).Soil total phosphorus drove variations in species diversity and phylogenetic structure across all understory layers in secondary forests(P<0.05).Available soil potassium and organic matter significantly influenced these patterns in natural forests(P<0.05).[Conclusion]Tree layer assembly favored stochastic dispersal during secondary forest restoration,while environmental filtering dominated in primary forests.Abiotic environmental filtering governed shrub layer dynamics across both forest types.Herb layer assembly primarily resulted from competitive exclusion.Managers should prioritize enhancing phosphorus availability in initial secondary forest recovery.Primary forest management must focus on maintaining topsoil organic matter turnover and nutrient cycling processes.