Understanding the evolutionary and environmental sources of spectral variation within species, communities and across the plant tree of life to enhance biodiversity detection

Abstract:

Detecting and assessing trends in biodiversity is critical to managing our life support systems to promote human wellbeing and long-term sustainability. The interaction of photons from the sun with Earth’s biota gives rise to spectral variation that can be detected from leaves to biomes. Meaningful interpretation of spatial and temporal trends in this variation are critical to advancing our capacity to monitor and assess biodiversity and the ecosystem services that flow from it. Yet we still have major gaps in our understanding of the mechanistic basis of spectral variation at different biological scales. The study of spectral reflectance in model species and model clades facilitates understanding of the linkages between genetic variation within species and variation across the tree of life. The use of common gardens enables the genetic and environmental components of spectral variation to be teased apart. Furthermore, understanding the common and disparate sources of variation at the leaf, canopy and community scales of vegetation diversity contributes to an expanding framework for measuring and monitoring plant function and phylogenetic composition across scales. This presentation draws on empirical examples within ecologically and agriculturally important model plant species and clades to examine the sources of spectral variation from genes and molecules to leaves and canopies, and from canopies to communities and landscapes. In doing so, we consider the role of environmental variation, genomic and metabolomic variation within and among species, as well as species interactions, in the expression of spectral and trait variation across biological scales.