The geography of tall trees and their demise across the Amazon basin: an ALS perspective

Using airborne lidar surveys, researchers have found the tallest tropical tree ever recorded – a 100 m dipterocarp in Borneo – and the tallest tree in the neotropics - an 88 m Dinizia tree in Brazil. Why do trees grow exceedingly tall in some places and why tropical forest canopies vary in height at the regional scale? Are tall trees on the best soils? Are short forests located where disturbances are most frequent? We are starting to find out thanks to a remarkable lidar dataset collected by Brazilian researchers, comprising over 500 transect sampling the entire Brazilian Amazon. In my talk, I will discuss three papers that evaluate the drivers of tree height, patterns of mortality as revealed by treefall gaps, and some recent work on gap dynamics.