Adaptation of functional traits and their plasticity of three ornamental trees growing in urban environment

Abstract Ornamental plant trees possess multiple ecosystem roles, retain ambient quality and have pleasant landscape effects, whereas urbanization also induce many environmental changes compared with rural areas and these changes affect the plants leaf functional traits. In response to these stresses, functional traits of plants may change. Here, we studied leaf functional traits and plasticity for three ornamental species growing under various levels of urban environment stresses. The results showed that leaf and stomatal traits varied between trees growing under different environment stresses. For all three species, as environment stresses increased, LT (leaf thickness), SLI (single leaf area), FAA (fluctuating asymmetry based on leaf area) and FAW (fluctuating asymmetry based on leaf width) decreased. Spatial distribution maps for SLA (specific leaf area) showed a high spatial variation, corresponding with the level of urbanization. These results suggest that stomatal traits of ornamentals tree species may potentially be used as indicators for urban habitat quality.