Stand structure and dynamics in the temperate rain forests of Chiloe Archipelago, Chile.

Abstract

Stands were dominated by broad-leaved evergreen trees and had in common the presence of several species of Myrtaceous trees in their canopies. Structurally, the forests were dominated by different species, although overall species composition was similar. Drimys winteri was dominant in Talcan and Chaulinec, Aextoxicon punctatum, was dominant in Alao, and Amomyrtus luma was dominant in Isla Grande. Laurelia philippiana, A. luma and Myrceugenia planipes were common to all forests. Nothofagus dombeyi was only present in Talcan, represented by a few, large emergent trees. The distribution of individuals by dbh classes showed that the forests of Alao and Chaulinec are dominated by individuals in the smallest dbh class (c50% of all stems). In the other forests, those individuals made up only 20% of the canopy, and larger trees were more common. Because of the smaller size and relative isolation of the forest patches in Alao and Chaulinec, this pattern might be attributed to invasion of these stands by species. This result is consistent with tree fall gaps. A broader scale of patchiness, related to the episodic occurrence of stand-devastating disturbances, could explain the persistence of Nothofagus domebeyi populations in Talcán. Recruitment of seedings and saplings in the forests studies was positively correlated with the abundance of each species in the canopy. Accordingly, dominance will be maintained in these forests in the absence of standisrupting disturbances.