title: Winners and losers in the competition for space in tropical forest canopies.
abstract: Trees compete for space in the canopy, but where and how individuals or their component parts win or lose is poorly understood. We developed a stochastic model of three-dimensional dynamics in canopies using a hierarchical Bayesian framework, and analysed 267,533 positive height changes from 1.25 m pixels using data from airborne LiDAR within 43 ha on the windward flank of Mauna Kea. Model selection indicates a strong resident's advantage, with 97.9% of positions in the canopy retained by their occupants over 2 years. The remaining 2.1% were lost to a neighbouring contender. Absolute height was a poor predictor of success, but short stature greatly raised the risk of being overtopped. Growth in the canopy was exponentially distributed with a scaling parameter of 0.518. These findings show how size and spatial proximity influence the outcome of competition for space, and provide a general framework for the analysis of canopy dynamics.
authors.affiliation: Department of Ecology and Evolutionary Biology, Brown University, Providence, RI, 02912, USA.
authors.forename: James R
authors.initials: JR
authors.lastname: Kellner
authors.forename: Gregory P
authors.initials: GP
authors.lastname: Asner
mesh_terms: D017753:Ecosystem; D006254:Hawaii; D008954:Models, Biological; D014197:Trees / Q000502:physiology*; D014329:Tropical Climate
keywords: Hawaii; LiDAR; disturbance; growth