TreeSpec: Quantifying the functional role of canopy structural and chemical traits for productivity across experimental tree diversity gradients using a hyperspectral imaging system

• Applicant: Professor Dr. Michael Scherer-Lorenzen, since 7/2018
• Subject Area: Ecology and Biodiversity of Plants and Ecosystems
• Term: from 2016 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 316733524

Quantifying canopy structure and physiology is integral to understanding tree species influences on forest ecosystem function, but the height and complexity of forest canopies makes sampling challenging. To date, next generation tools for canopy research that measure plant traits from a birds-eye-view perspective, such as near-canopy Unmanned Aerial Vehicles (UAVs) equipped with hyperspectral imaging, have predominantly focused on crop monocultures. Few, if any studies have applied these tools to examine more diverse mixtures or forest canopies. Therefore, we propose to address this knowledge gap by testing UAV-based remote sensing methods for the measurement of key traits driving forest productivity and examining their relationship to tree species diversity in experimental communities. Recent analyses suggest forest productivity largely depends on two key canopy traits: 1) leaf area index (LAI), which describes light capture, and, 2) canopy leaf nitrogen (%N), which describes biochemical carbon fixation. Together, these traits may mechanistically link carbon fluxes and forest canopy attributes at broad temporal and spatial scales. However, tests of the generality of these relationships in other regions and for different species pools are needed. Focusing on two of the longest-running tree diversity experiments in the world, we will collect and compare observations of LAI and %N from the ground and the air and test their relationship with productivity. Effects of neighbourhood species and functional composition on crown shapes, LAI and %N relative to monoculture will be detected at high resolution using a state of the art UAV-imaging system. This will allow for novel studies of intraspecific trait variation in relation to architectural complementarity and productivity. Our project will thus accomplish two main goals: the development of novel methods of measuring key canopy traits, and the assessment of their potential role in diversity-productivity relationships.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Professor Dr. Charles Nock, until 7/2018