Variation in leaf economics spectrum between plant functional types and the coordination with vein density in a subtropical urban forest of Eastern China

Abstract Key message Evergreen and deciduous species in a subtropical urban forest of Eastern China exhibit pronounced differences in leaf traits, with evergreens species showing lower photosynthetic rate on a leaf mass basis and leaf nutrient contents, but higher leaf mass per area ratio, leaf thickness, leaf carbon content, and leaf carbon-to-nitrogen ratio, whereas deciduous species show the opposite pattern, reflecting distinct resource-use characteristics. In addition, leaf economic and hydraulic traits are coordinated, with higher vein density associated with higher scores along the leaf economics spectrum PCA axis, reflecting resource-acquisitive characteristics and highlighting vein density as a key trait linking water transport capacity to carbon economy. Context Understanding how leaf economics and hydraulic traits vary and interact among different plant growth forms and leaf habits is essential for elucidating plant adaptability. However, the coupling of these two trait dimensions remains unclear within urban forest ecosystems where environmental conditions differ significantly from natural forests. Aims This study aimed to investigate variation and coordination between leaf economics and hydraulic traits among woody species in a subtropical urban forest of Eastern China, focusing on differences between leaf habits and growth forms. Methods We measured 10 leaf economic traits and 4 hydraulic traits across 53 woody species from a subtropical urban forest. Results Evergreen species exhibited lower photosynthetic rate on a leaf mass basis, leaf nutrient contents, and higher leaf mass per area ratio, leaf thickness, leaf carbon content, and leaf carbon-to-nitrogen ratio, consistent with resource-conserving characteristics. Deciduous species showed higher values of these parameters, indicative of rapid resource acquisition. Shrubs displayed significantly higher phosphorous content in leaves than trees. Vein density was positively correlated with the leaf economic spectrum. Conclusion These findings reveal a coordination between leaf hydraulic and economic traits. This coupling highlights the balance between water transport and resource acquisition characteristics.