Integração funcional da arquitetura hidráulica em árvores de platô e baixio na Amazônia Central

Abstract

Soil water availability has a significant impact on various aspects of the plant phenotype, making it crucial to examine plant water relations from an integrated perspective. Here, we examined whether plant traits related to water-use were functionally integrated into a unified hydraulic architecture network, and evaluated whether species associated with contrasting soil-water conditions had different integration patterns of their hydraulic architecture. We analyzed the interspecific correlations among 11 functional traits of 28 canopy species associated with valleys and plateaus in a Central Amazonian forest. Next, we computed traits as nodes in a network and the significant correlations between pairs of traits as links between nodes, and calculated the network's edge density, average distance and average clustering. When pooling valley and plateau species, taller trees had few larger vessels and stomata, thicker bark, low SLA leaves, and low proportions of stem sapwood area of taller trees. Plateau species exhibited a stronger integration pattern, with high clustering among tree height, bark thickness, and vessel and stomatal traits, while valley species displayed a more sparsely connected network with no specific trait or set of traits holding more relative importance in the network topology. Our results suggest that height-related constraints tightly couple together the water and carbon use in canopy species, especially among species adapted to drier conditions (plateaus) than those adapted to wetter conditions (valleys) in a Central Amazonian forest.