Características funcionales del género arborescente Polylepis en un gradiente latitudinal en los altos Andes

SUMMARY Polylepis is a genus restricted to the Andean Mountain Range, naturally occurring above the upper continuous forest limit. The purpose of this work was to integrate and compare functional characteristics in terms of water and carbon rela‑ tions and low temperature resistance mechanisms in different Polylepis species along a latitudinal gradient. The studied species were P. sericea in Venezuela, P. tarapacana in Bolivia and P. australis in Argentina. Seasonal measurements of leaf water and osmotic potentials, stomatal conductance, CO2 as‑ similation and respiration rates, and injury and freezing tem‑ peratures were compared. There is a gradient, in terms of functional attributes, along the environmental range. P. tarapacana is the most tolerant species to water stress, while P. seri