You are here

Harvard Forest >

Harvard Forest REU Symposium Abstract 2019

  • Title: Understanding Spectral Reflectance in Deciduous Forests: From Leaves to Canopies
  • Author: Alexis R Helgeson (Mount Holyoke College)
  • Abstract:

    Forest productivity depends on many different variables including which tree species live in a forest (Humagain et al. 2017). Remote sensing technology uses spectral signature analysis to estimate the upper canopy tree demography of a forest (Kotlarz et al. 2016). The spectral signature of a tree is the unique reflectance of the tree compared to the known light spectrum (Cerasoli, Costa e Silva & Silva 2016). The spectral signature of leaves is an indicator of biophysical differences between tree species such as size, chlorophyll content, and water content (Zarco-Tejada et al. 2000). Other studies demonstrate that the spectral signature of a tree varies depending on the tree species (Zhao et al. 2016). However, most of these studies were done using satellite remote sensing data as opposed to field collected data. This study evaluated field spectral measurements of red oak and red maple trees at the Harvard Forest research site in Petersham, MA to compare the spectral signature within and between tree species. This study compared field-collected data within and between the red oak and red maple species using a separability analysis and a PCT (principal component transformation) in R to better understand the differences in tree spectral signatures. The red oak and red maple spectral differences correlated with the biophysical differences in the leaf properties. Cementing our understanding of tree species spectral signatures will lead to improvements with remote sensing technology and allow researchers to more easily collect and interpret existing data.

  • Research Category: Ecological Informatics and Modelling; Forest-Atmosphere Exchange; Group Projects; Physiological Ecology, Population Dynamics, and Species Interactions