96th ESA Annual Meeting (August 7 -- 12, 2011)

PS 10-125 - Effects of habitat degradation on the regeneration of an Andean tree species (Polylepis tomentella, Rosaceae)

Monday, August 8, 2011
Exhibit Hall 3, Austin Convention Center
Alejandra I. Domic, Biology, Saint Louis University, St. Louis, MO and Gerardo Camilo, Department of Biology, Saint Louis University, St. Louis, MO
Background/Question/Methods

The human alteration of ecosystems constitutes a serious threat to tree species. This is more intense in developing countries where mountain forests provide firewood and area for farming. In the Neotropics, mountain forests have been highly impacted by small-scale activities such as selective logging, burning, and farming. Polylepis is a genus composed by small trees that occur at the upper limit of mountain forests, between 3,000 and 4,800. Despite human activities have impacted Polylepis populations extensively, there is little quantitative data on the impacts of logging and framing. This study compares changes in habitat conditions and population structure of Polylepis tomentella (Rosaceae) in populations highly and lilted degraded. Populations were categorized based on the proportion of logged trees and farming area.

Results/Conclusions

Results show significant differences in soil chemical composition between highly and little degraded populations. Seedling’s density was higher in little degraded populations, while no differences were found regarding the density of adults. Moreover, in highly degraded populations, reproductive individuals produced higher quantities of flowers and fruits. Our data suggest that the regeneration of P. tomentella is not limited by seed production and that changes in soil chemical properties my decrease seed germination and increased seedling mortality.