Dr. Brenden McNeil

Testing tree crown economics with the National Ecological Observatory Network

With a historic public investment to build and maintain the National Ecological Observatory Network (NEON), ecological science is entering a new era where systematic, multi-scale data are now freely available to rigorously test of theories linking the traits of individual organisms to the functioning of a continent’s ecosystems.  In this presentation, I detail a collaboration with NEON that is testing a novel theory of tree crown economics. We began by working with NEON staff to install timelapse cameras level with the sunlit portions of tree crowns next to 11 NEON towers throughout the broadleaf deciduous forest biome of the eastern United States.  From these cameras, WVU undergraduate researchers have made over 21,000 measurements of leaf angles. We have been relating the spatial and temporal patterns in leaf angle to other routinely-collected observations, including (1) other tree crown architectural traits measured from NEON’s airborne LiDAR instrument, (2) spectral indices of individual tree functioning made from satellites, NEON’s airborne imaging spectrometer, and phenocams on each NEON tower, and (3) NEON tower-based environmental sensor data.  Synthesis of these data suggest that leaf angle is a key part of a suite of crown architectural traits that help govern a tree’s economic trade-off of maximizing photosynthesis, minimizing evapotranspiration, and winning the competition for light.  I conclude by discussing how NEON data provide a new lens to forecast how the economic strategies of individual organisms will continue to strongly affect the responses of ecosystems to a changing environment.