Anna Lee Jones, Christian Pfrang, Felicity Hayes, Elizabeth S. Jeffers, Ecological Indicators, Volume 172, 2025, https://doi.org/10.1016/j.ecolind.2025.113263
Our latest paper published in Ecological Indicators demonstrates that hyperspectral monitoring can detect ozone damage in mature oak trees. We compared high resolution leaf reflectance at Wytham Woods and the BIFoR forest, and accurately predicted ozone exposure from leaf reflectance alone via machine learning. Our ozone monitoring revealed that Wytham Woods has significant ozone exposure, which has important implications for the entire ecosystem and warrants further monitoring. This study builds on our experimental work at the CEH Air Pollution Facility (https://doi.org/10.1016/j.envpol.2024.124642) and was made possible by equipment loan from the NERC Field Spectroscopy Facility, and the enthusiasm of collaborators at the Birmingham Institute of Forest Research.
Abstract
At the near-surface, ozone (O3) is a toxic pollutant which has reached dangerously high concentrations across the world and is predicted to continue to rise. O3 reduces the growth, productivity and resilience of trees but the extent of O3 damage to forests is uncertain. To develop a high throughput method of monitoring O3 damage to forests, we pioneer hyperspectral monitoring of O3 damage in adult oak trees across a range of naturally occurring O3 concentrations. Using a machine learning approach, we demonstrate accurate prediction of O3 exposure of trees from hyperspectral leaf reflectance alone. This method could be used for forest level assessments of O3 damage. Vegetation indices characterising green reflectance and red-edge track O3 induced changes in leaf reflectance. Vegetation indices have the potential to scale up O3 damage monitoring across spatial scales. As O3 concentrations continue to rise globally, understanding the extent of O3 damage to forests is crucial to effectively harness the carbon sequestration potential of forests. We demonstrate the exciting potential of spectral monitoring of O3 damage in mature trees under natural conditions.
