Abstract:Urbanization will induce substantially environmental changes. However, the potential effects of urbanization on plant functional traits are still not understood. In this study, the dominant species Schima superba Gardn. et Champ. was selected to measure the plant leaf and shoot functional traits under both sunlit and shaded conditions along the urbanization gradients (including urban site HZ, suburban site FY and rural site JD) around the urban center Hangzhou. Two-way analysis of variance (Two-way ANOVA) and multiple comparisons (Tukey) were conducted to analyze the differences of those traits among the three studied sites, and the differences between sunlit and shaded traits for different sites, as well as the sensitivity to the urbanization were also compared. Pearson correlation analysis was adopted to detect the relationships among these functional traits and the meteorological factors of the three sites. The Two-way ANOVA indicated the co-varying of these functional traits due to the urbanization. Specifically, the hydraulic traits including shoot density (ρ), specific leaf area (SLA), and leaf shoot ratio (AL:AS) were found to decrease, while the sapwood area specific hydraulic conductance (KS) increased significantly. The shaded traits shifted in the same way, with the exception of the AL:AS. As to the gas exchange traits, the sunlit leaf maximum photosynthetic rate (An), transpiration rates (El), and stomatal conductance gs increased from JD to HZ sites, among which, the El at HZ site was 2.8 folds of that at JD site. The water use efficiency (WUE) and abundance of 13C (δ13C) in HZ was also decreased significantly. Besides, the shaded traits shared the same pattern with the exception of the An(P > 0.05). In addition, the comparisons between sunlit and shaded traits showed significant difference between these two groups and the sunlit traits had higher sensitivity in response to the urbanization. Our results indicated that plants hydraulic traits and gas exchanges traits were highly related, especially for the relationships between KS and the An, El (P<0.05). Besides, the variation of temperature (Ta) and vapor pressure deficit (VPD) have significant effect on the hydraulic traits. These results could provide some evidence that urbanization would lead to the shift of survival strategies into high gas exchange ability and low hydraulic threshold.