Fundamental axes of life-history variation in tropical tree species

• Applicant: Dr. Nadja Rüger
• Subject Area: Forestry
• Term: from 2010 to 2012
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 171164904

Morphological traits of tropical tree species integrate to demographic rates which, in turn, determine forest dynamics. I propose to link two data sets – on demographic rates and morphological traits of >250 tree species at Barro Colorado Island (BCI), Panama – to identify fundamental axes of life-history variation among tropical tree species. Based on previous analyses of light and size dependence of recruitment, growth and mortality rates, I aim to perform a joint analysis to determine few independent dimensions that capture essential demographic variation among the tree species. A hierarchical Bayesian approach allows including information on rare species in the analysis by correctly weighting by their abundance. To associate meaning to the demographic dimensions, I aim to perform correlation and regression analyses to establish relationships between 16 morphological traits and the demographic axes. This analysis will yield a novel predictive model for demographic rates of the tree species at BCI on the basis of easily measurable traits. Finally, I aim to perform a cluster analysis based on the demographic axes to group demographically similar species. The derived species groups have the potential for use in many other life-history studies of BCI trees and can serve for the parameterization of an individual-based forest model which could be used to make predictions about coexistence and forest dynamics.

• DFG Programme: Research Grants