Abstract: The karst forests in the subtropical region of Southwest China harbor a rich diversity of deciduous and evergreen broad-leaved trees. Understanding their phylogenetic and functional diversity and the driving factors is key to elucidating mechanisms of community assembly and species coexistence in the karst forests. Focusing on woody angiosperms across 29 forest plots in Junzi Mountain in eastern Yunnan Province, we employed generalized linear models and Mantel test to analyze how environmental conditions and human disturbance shape diversity patterns. The results showed that: (1) Deciduous broad-leaved plants exhibited lower phylogenetic α-diversity (SES.MPD) but higher functional α-diversity (SES.MFPD) than their evergreen counterparts. While their phylogenetic β-diversity (SES.betaMPD) was similar, deciduous species showed significantly higher functional β-diversity (SES.betaMFPD). (2) Phylogenetic α-diversity in both tree types varied with soil type, being higher in black limestone soils than in brown limestone soils. However, their functional α-diversity responded to different drivers, which was correlated with human disturbance intensity in deciduous plants, but with slope aspect in evergreen plants. (3) The phylogenetic β-diversity of deciduous plants was influenced by human disturbance, whereas that of evergreen plants showed no environmental or anthropogenic correlations. Conversely, functional β-diversity varied with human disturbance in deciduous plants, but with slope aspect and soil type in evergreen plants. Our results revealed a clear divergence in the phylogenetic and functional diversity patterns of deciduous and evergreen broad-leaved trees in eastern Yunnan’s karst forests, reflecting their distinct adaptation strategies. These findings underscore the need for differentiated conservation and management approaches tailored to each plant functional type.

Key words: biodiversity, leaf habit, calcareous soil, α diversity, β diversity