Fully exposed canopy tree and liana branches in a tropical forest differ in mechanic traits but are similar in hydraulic traits----中国科学院西双版纳热带植物园

Large lianas and trees in the forest canopy are challenged by hydraulic and mechanical failures and need to balance hydraulic conductivity, hydraulic safety and mechanical safety. Our study integrates these functions in canopy branches to understand the performance of canopy trees and lianas, and their difference. We sampled and measured branches from 22 species at a canopy crane in the tropical forest at Xishuangbanna, SW China. We quantified the hydraulic conductivity from the xylem-specific hydraulic conductivity (KS), hydraulic safety from the cavitation resistance (P50) and mechanical safety from the modulus of rupture (MOR) to evaluate trade-offs and differences between lianas and trees. We also measured a number of anatomical features that may influence these three functional traits. Our results suggest that: Trade-offs between hydraulic conductivity, hydraulic safety and mechanical safety are weak or absent; Liana branches better resist external mechanical forces (higher MOR) than tree branches; Liana and tree branches were similar in hydraulic performance (KS and P50). The anatomical features underlying KS, P50 and MOR may differ between lianas and trees. We conclude that canopy branches of lianas and trees diverged in mechanical design due to fundamental differences in wood formation, but converged in hydraulic design.

论文下载:

下载地址

关闭窗口

返回首页

西园公告