He Dong, Yan En-Rong, Zheng Li-Ting, Song Yan-Jun, Yang Xiao-Dong, You Wen-Hui, Cornelissen J Hans C
College of Ecology and the Environment, Xinjiang University, Urumchi, China.
Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China.
Front Plant Sci. 2025 Jul 24;16:1616656. doi: 10.3389/fpls.2025.1616656. eCollection 2025.
Maximum height (H) is a principal driver or correlate of interspecific variation in many plant functional traits. Still, it remains unclear why leaf resource economic traits are invariant with H at global scale and why broad-scale interspecific trait correlations are not retained at local scale. Here we proposed that the actual plant height (H), which is tightly linked with highly localized abiotic and biotic interactions, is more important than H in determining plant morpho-physiological traits among locally co-occurring plants. We tested the idea across community, regional, and global scales. We also examined correlations among 22 traits, including leaf physiology, hydraulics, and crown architecture, within a subtropical forest in Eastern China. Additionally, we explored how H-driven trait variations align with vertical patterns of microclimates. Results showed stronger correlations between leaf traits and H at the community level, except for leaf area. Intraspecific variation exceeded interspecific variation, and trait correlations were stronger at the individual level than at the species level. H positively correlated with traits like crown area, leaf mass per area, stomatal density, and hydraulic conductivity but negatively with stem hydraulic safety margin and leaf coverage. Vertical changes in photosynthetically active radiation explained most H-driven trait variations. Our findings suggest that H influences plant trade-offs in biomass allocation and photosynthetic-hydraulic limitations, shaping functional diversity within communities. This highlights H as a key factor in balancing resource use, support, and water transport among coexisting plants.
最大高度（H）是许多植物功能性状种间变异的主要驱动因素或相关因素。然而，目前尚不清楚为什么叶片资源经济性状在全球尺度上与最大高度无关，以及为什么广域种间性状相关性在局部尺度上不能保持。在此，我们提出实际株高（H）与高度局部化的非生物和生物相互作用紧密相关，在决定局部共存植物的形态生理性状方面比最大高度更重要。我们在群落、区域和全球尺度上对这一观点进行了检验。我们还在中国东部的一个亚热带森林中研究了包括叶片生理、水力和树冠结构在内的22个性状之间的相关性。此外，我们探讨了由最大高度驱动的性状变异如何与小气候的垂直格局相匹配。结果表明，除叶面积外，在群落水平上叶片性状与最大高度之间的相关性更强。种内变异超过种间变异，且性状相关性在个体水平上比在物种水平上更强。最大高度与树冠面积、单位面积叶质量、气孔密度和水力传导率等性状呈正相关，但与茎水力安全边际和叶覆盖率呈负相关。光合有效辐射的垂直变化解释了大多数由最大高度驱动的性状变异。我们的研究结果表明，最大高度影响植物在生物量分配和光合-水力限制方面的权衡，塑造了群落内的功能多样性。这突出了最大高度是平衡共存植物间资源利用、支撑和水分运输的关键因素。
