OOS 51-5 - Assessing foliar functional traits throughout the North American NEON domains using imaging spectroscopy

Foliar functional traits offer insight into ecosystem processes from productivity to reproduction and decomposition. Across environmental, climatic, and diversity gradients, these traits vary in ways that can be linked to landscape and ecosystem differences, offering insight into what specific mechanisms are driving variation in ecosystem function. At the landscape level, hyperspectral remote sensing offers a unique opportunity to quantify these traits at scale, allowing for analysis of trait patterns across gradients and through time. At more local scales, higher resolution imagery enables us to examine different diversity metrics and how they change within and between sites. We utilize hyperspectral imagery collected by the NEON airborne observation platform at their sites across the United States from 2013-2022 together with partial least squares regression models to estimate 29 foliar functional traits. We examine trait-trait relationships and compare them against environmental gradients such as elevation and landscape position, atmospheric variables such as deposition, as well as against climatic variation such as rainfall, aridity, temperature, and solar conditions, in addition to soil characteristics. We also analyze different metrics of diversity across the landscape and assess how these traits relate to those metrics at different scales. This analysis allows for a more thorough understanding of the current landscape conditions, as well as how ongoing anthropogenic changes will affect plant communities across ecosystems and what that means for future forest systems.