Relações entre caracteres anatômicos do xilema, densidade de madeira e segurança hidráulica em espécies do semiárido

Abstract

Anatomical characteristics of the stem are important to understand the life history strategies of species in seasonally dry environments, as well as their resistance and maintenance of the water column in the xylem from the roots to the branches. Thus, we selected five tree species present in the semi - arid region of Northeast Brazil to understand the relationship between the anatomical characteristics of xylem, wood density, safety and hydraulic conductivity under water stress. For this, we performed a principal components analysis with the studied variables and observed their influence within the species. As a general pattern for all species, the characters studied were also correlated and it was possible to perceive conflicting demands among the variables. We verified that anatomical characteristics of xylem can vary between species with the same density of wood and this reflects in the indices of safety and conductivity. On the other hand, species with different wood densities share common aspects of anatomy, safety or conductivity, forming homogeneous groups.