Hydraulic structure and wood density from root to the crown in in three native Brazilian tree species

Abstract

We study anatomical and hydraulic features of vessels and wood density, and correlations between them, from root to crown in 40-year-old Balfourodendron riedelianum, Cariniana legalis and Handroanthus vellosoi trees. We didn't observe gradual tapering of vessel diameter along the tree axis, but hydraulic bottlenecks from stem top to the crown base were noted. Vessel density, did not vary from root to stem, but it was higher in the crown. Vessel features promotes changes in potential hydraulic conductivity, and these changes vary among species, highlighting that the interaction between vessel density and vessel diameter affected potential hydraulic conductivity. Higher values of wood density at trees bases demonstrated an investment in mechanical sustentation. Our results showed a certain synergy between anatomical features and hydraulic conductivity that promotes anatomical adjustments required to meet the hydraulic and mechanical requirements of these tropical trees.