Plant Hydraulics on Barro Colorado Island, Panama

Water movement from soil through trees to the atmosphere in the transpiration stream is a major component of Earth’s water cycle. Barro Colorado Island (BCI), Panama, has hosted research at the forefront of plant hydraulics, a field that aims to discover the mechanisms that drive variation in transpiration among plants and in response to environmental conditions. Work on BCI has shown that tropical tree species vary in the soil depths at which they extract water, the water-moving efficiency of their vascular systems, and the vulnerability of their vascular systems to water deficit during seasonal and extreme droughts. Combined, these factors lead to diverse patterns of transpiration among tropical trees, which affect dynamics of tree growth and mortality. The understanding gained on BCI has helped to form the basis for predicting how transpiration in individual trees and in tropical forests will respond to climate change.