Condit et al.: Growth and Mortality of tropical tree species in Sinharaja, Sri Lanka

Growth and mortality rates were calculated for all tree species in the 25 hectare plot established in a lowland evergreen dipterocarp forest in the southwestern region of Sri Lanka, a UNESCO National World Heritage Site The plot was established in 1993 by the University of Peradeniya, the Forest Department of Sri Lanka, Harvard Institute of International Development, and the Smithsonian Tropical Research Institute. There is no marked dry season, with annual rainfall averaging 5000 mm. All trees greater than or equal to 1 cm diameter at breast height were measured and tagged during 1993-1996 and 2001-2002. Relative growth rates were calculated for each individual tree using log transformed diameters, annualized by the time interval between census measurements, then averaged within species. Outliers were excluded: stems that grew greater than 75 mm per year or shrunk more than 25% of their initial dbh. The mortality rate constants were calculated using the number of trees alive in the first census, number of survivors in the second census, averaged over the time interval.