The more than 20,000 species of trees estimated to occur in Amazonian forests represent an astounding morphological and physiological diversity, often within a single family or genus. To what extent do the remarkably diverse morphologies we observe among tropical plants permit them to partition resources and coexist? What are the implications for responses of forests to global changes? The measurement of morphological and physiological traits for different species across environmental gradients can contribute to answers to these important questions.

Our laboratory manages three large datasets of functional traits of tropical woody plants, and we contribute to the development of interactive databases for managing trait data.

The BRIDGE dataset

The BRIDGE trait dataset was collected (i) to examine functional trait correlations for a large number of tropical tree species, (ii) to examine the extent to which functional strategies are phylogenetically conserved, and (iii) to contrast functional and phylogenetic signals of community assembly in tropical tree communities. A full description of the project can be found here, and a description of the trait database and online access is here.

The AmaLin dataset

The AmaLin trait dataset was collected to expand definitions of functional strategies across broad geographic and environmental gradients. Using the extensive plot network we have established for the project, we have sampled more than 800 species across terra firme clay, white sand and seasonally flooded forests in Peru and French Guiana. Results are forthcoming.

Regeneration and Seedling Traits

We also have a large seedling trait database that compiles reproductive traits at the species level (Baraloto & Forget 2007) with data from morphological and physiological measures performed under controlled conditions.

Since 2003 we have been using shadehouse experiments to examine seedling morphological and physiological traits and performance under controlled conditions. The main objective of this work is to examine variation in functional strategies within vs. among different lineages of tropical trees. To date we have studied more than 60 species with at least two species in 8 genera and three species in 4 genera. In four of these genera we found patterns of divergence consistent with lineage diversification and habitat specialization (Baraloto et al. 2007). More results will appear soon.

All of these datasets are in the process of being integrated into the Mariwenn trait database managed by the UMR EcoFoG. Full details can be found in Ollivier et al. 2007.

An illustration of BRIDGE project data, by Tim Paine