University of Pittsburgh Department of Biological Sciences Presents:
Monday Fall 2017 Seminar Series
Dr. Scott Stark
Michigan State University
"Towards remotely sensed canopy function and forest dynamics, to understand forest change and its consequences for the atmosphere"
Forest structure and dynamics are changing rapidly around the world as a consequence of climate-change-related pests, droughts and wildfires, and human use. It is critical to understand these changes at the process level (e.g. demographic performance of trees) to accurately predict subsequent forest responses, including impacts on carbon and water cycles, surface-atmosphere energy dynamics, and ecological communities. Remote sensing may offer a critical tool to assess and understand these changes at large scales if it can connect observations of forest canopies to underlying biological processes such as demography. To be effective such an approach must be able to assess the full spectrum of forest demographic groups, including those that fall primarily in the shade of larger trees. I ask whether recent advances can answer this challenge by reconstructing high-resolution canopy structure in 3D from airborne LiDAR data and then associating LiDAR derived leaf area strata and leaf area light environments with the stem frequency, biomass and performance of trees in different demographic groups. Focusing on Amazonian forests, I show that forest structure (e.g., size distributions) and function (tree turnover) can be retrieved with this approach, though only after accounting for tree architecture over light environments. I conclude by highlighting an investigation taking this approach to develop understanding of changing connectivities between forested ecosystems globally, including across continents, resulting from ecoclimate teleconnections.
Monday, October 30, 2017