INTERANNUAL VARIATION IN SEED PRODUCTION BY TREE SPECIES OF THE COAST RANGE IN SOUTH-CENTRAL CHILE

Abstract

This study analyzes interannual variation and synchrony of seed production of native tree species in Cordillera Pelada, south-central Chile. We analyze seed production data collected by Donoso (1993) and Donoso (1993) et al. at two sites, occupied by Valdivian rainforest and Fitzroya cupressoides forest, for periods of 10 and 7 years, respectively. There was wider interannual variation at the higher-altitude site dominated by F. cupressoides, than at the lower-altitude Valdivian rainforest site. In contrast, there was no significant difference in variability between wind-pollinated and insect-pollinated species. At neither of the two sites was there significant synchrony of seed production among the species of the assemblage. There was, however, significant synchrony between the two populations of the only species common to both sites, Drimys winteri. Precipitation, and especially summer and winter temperatures were correlated with seed production in some of the species at both sites. Results suggest that the effect of the site on plant populations is an important element to consider to clarify synchrony between species and mast seeding.