Multi-year observations of BVOCs and ozone: concentrations and fluxes measured above and below the canopy in a mixed temperate forest

作者：Clément Dumont, Bert Verreyken, Niels Schoon, Benjamin Bergmans, Bernard Heinesch, Crist Amelynck · 发表于：Earth system science data · 年份：2026 · DOI：10.5194/essd-18-617-2026 · 被引用次数：2 · 研究领域：Atmospheric chemistry and aerosols、Plant responses to elevated CO2、Plant Water Relations and Carbon Dynamics

Abstract. Volatile organic compounds (VOCs) and ozone (O3) are key constituents of tropospheric chemistry, affecting both air quality and climate. Forests are major emitters of biogenic VOCs (BVOCs), yet large uncertainties remain regarding the diversity of exchanged compounds, the drivers of their bidirectional fluxes, and their in-canopy chemistry. Long-term and comprehensive in situ datasets remain scarce, limiting our understanding of these complex processes. We conducted a 3-year field campaign (2022–2024) at the Integrated Carbon Observation System mixed temperate forest station of Vielsalm (BE-Vie), combining vertical concentration profile and eddy covariance flux measurements above and below the canopy (concentration dataset: https://doi.org/10.18758/NVFBA74V, Verreyken et al., 2025c; flux dataset: https://doi.org/10.18758/KHV8ZXU2, Dumont et al., 2025a; concentration-turbulence profile dataset: https://doi.org/10.18758/BED4Q2VY, Dumont et al., 2025b). Using a PTR-ToF-MS and an open-source data-processing workflow, we identified 48 significantly exchanged VOCs. The vertical and diurnal gradients of the mixing ratios reflected the interplay between emission, deposition, chemistry, and transport. Combined with a profile of turbulence statistics, these observations offer an opportunity to investigate their behaviour within the canopy. The forest acted as a net VOC source in summer (∼ 1.25 µg m−2 s−1), while deposition dominated in autumn. Many oxygenated VOCs displayed b...