Relationships Between Diametral Growth Rate and Functional Traits of Tree Species in Tropical and Subtropical Forest

Abstract:

Exploring the correlation between tree functional traits and growth is helpful to predict the growth dynamics of tree species under climate change. A total of 56 dominant tree species were measured in 3 typical tropical and subtropical forest plots, including branch embolism resistance (P₅₀), water conductivity (k_s), wood density (WD), specific leaf area (SLA), and vessel anatomical traits. Diametral growth rate (DGR) of large diameter class (DBH≥15 cm), small diameter class (5-15 cm) and undifferentiated diameter class (≥5 cm) were calculated based on community survey data, and the correlation between traits and DGR was analyzed. The results showed that DGR of different diameter classes was positively correlated with k_s, but not with SLA, P₅₀ and vessel anatomical traits. WD and DGR with small diameter tree species were negatively correlated, but not with large diameter tree species. Therefore, it was suggested that xylem water conductivity could better predict the growth rate of tropical and subtropical forest trees than economic traits.

Key words:Xylem anatomy;Hydraulic efficiency;Embolism resistances;Growth rate;Wood density;Specific leaf area