Huang, Ya-LunYa-LunHuangSHANG-TZEN CHANGTING-FENG YEH2026-02-032026-02-032025-12-0413850237https://www.scopus.com/pages/publications/105024011691?inwardhttps://scholars.lib.ntu.edu.tw/handle/123456789/735754Article number 4Plants in different ecological niches exhibit distinct leaf functional traits, and within a species, individuals can adjust these traits in specific environments. Both Chamaecyparis formosensis and C. obtusa var. formosana are dominant species in the montane cloud forests of Taiwan, but C. formosensis saplings dominate in open gaps while C. obtusa var. formosana saplings are more common under shade. To determine whether the saplings of these two species feature different leaf traits and phenotypic plasticity, saplings of both species were cultivated in different light environments, and their leaf functional traits were studied. The results showed that C. formosensis featured significantly thicker leaves (p = 0.01) and higher chlorophyll contents (p < 0.02), photosynthetic rate (p < 0.001) and stomatal conductance (p < 0.001) than C. obtusa var. formosana. In terms of plasticity, C. formosensis exhibited a significantly greater increase in photosynthetic rate (16%) under full light conditions compared to C. obtusa var. formosana (7%), whereas C. obtusa var. formosana showed significantly greater increases in specific leaf area (54%) and chlorophyll content per unit leaf dry weight (69%) under shade than C. formosensis (-2% and 12%). The differences in these traits and plasticity showed that C. formosensis demands more light than C. obtusa var. formosana, and C. obtusa var. formosana adapts better under shade. These differences reflect their ecological niches, and both species have greater plasticity in traits that are more essential to survival in their niches. These findings enhance our understanding of trait–environment coordination in closely related conifers and provide insight into species coexistence and forest regeneration dynamics.falseLeaf traitsLight intensityLight-demandingNichePlasticity indexShade-tolerantjournal article10.1007/s11258-025-01582-22-s2.0-105024011691