Structure and regeneration of Prumnopitys andina forests in the Andes of southern Chile

Abstract

Prumnopitys andina is a conifer tree species with a narrow distribution in Chile and Argentina. Despite its ecological importance, knowledge about the structure and dynamics of the forests where P. andina grows is limited. We aim to describe the structure and regeneration of forest with high presence of P. andina. Forests near Lonquimay (38°1' S, 71.3 W - 38°3'S, 71°3' W) were sampled by measuring trees, regeneration and vascular flora through 24 plots. We found that P. andina predominantly occurs in the upper canopy (15-18 m), usually in company of Nothofagus obliqua and/or Austrocedrus chilensis, in addition to Maytenus boaria and Lomatia hirsuta that occur in the mid-canopy (4-8 m). Based on forest structure, we identified three types of P. andina forests: open, secondary-mature, and pure. Pure P. andina forests reached basal areas among the largest reported for for temperate forests southern South America (230 m²/ha). P. andina regeneration ranged from 1,550 individuals/ha in open forests to 25,000 individuals/ha in pure forests. P. andina exhibited a continuous regeneration strategy, which in the absence of human disturbances, such as grazing by cattle or selective logging, suggests that its populations are self-sustaining.