PARENT SESSION
Contributed Oral Session 127: Forest Structure and Communities
Thursday, August 11, 1:30 PM - 5:00 PM, Meeting Room 513 A, Level 5, Palais des congrès de Montréal
Species richness across a >56-year chronosequence of dry tropical forest on Providencia Island, Colombia.
Ruiz, Jorge*,1, Fandino, Maria2, 1 Universidad de America, Bogota, Colombia2 Instiuto de Investigacíon de Recursos Biologicos Alexander von Humboldt, Bogota, Colombia
ABSTRACT- We estimated and compared species richness across chronosecuence classes of dry tropical forest on Providencia Island, Colombia, SW Caribbean, about 230 km from Nicaragua. This island has an area of 22 km2 and an annual precipitation of 1584 mm year-1 (Average for 1982-2000), with five months of drought. A chronosequence was established at the landscape level using orthorectified panchromatic aerial photos (1944 to 1996) and Landsat 7 ETM+ satellite imagery acquired in 2000. Along the chronosecuence, with six classes of abandonment age (less than 6 years, 6 to 10, 17 to 31, 32 to 56 and more than 56); we established 59 plots of 2 x 50 m (0.01 ha) to document changes in species richness and stem density. All woody trees and shrubs, except lianas, >2.5 cm DBH were censused. In a rarefied sample of 187 individuals, species richness was positively associated with increasing age since abandonment. Non-parametric estimators of species richness revealed different results. While Chao1 showed a positive and linear associations with chronosecuence, the Abundance Coverage Estimator or ACE peaked at intermediate ages of the chronosequence. Our results indicate rapid recovery of woody species richness along this tropical dry forest chronosequence, independent of the differences in stem density between chronosecuence classes.
Key words: dry tropical forest, rarefaction, species richness, succession