Continental-scale patterns of canopy tree composition and function across Amazonia

Researchers working in the Amazon basin/Guiana shield region have accumulated massive ecological data sets. Now that work has been brought together in a combined database covering over a quarter of a million trees, and providing information on a scale that can contribute significantly to our understanding of the Amazon ecosystem's biodiversity and its place in the global climate system. Two dominant gradients in tree composition and function across the Amazon are evident, reflecting patterns of soil fertility and differences in the length of the dry season. The data also suggest that dominance of legumes in the Guiana shield is due to high seed mass and low rates of disturbance, rather than root adaptations to poor soils.