Forest floor VOC emissions studied in Austrian pine and juniper stands

Researchers at the Forest Atmosphere Interaction Research (FAIR) station in Obermieming, Tyrol, Austria, have quantified volatile organic compound (VOC) fluxes from the forest floor in a Scots pine and juniper ecosystem. The study, conducted between April 17 and May 21, 2025, utilized a soil cuvette system combined with proton-transfer-reaction time-of-flight mass spectrometry (PTR-ToF-MS).

The research focused on two distinct locations: one characterized by needle-rich litter with sparse undergrowth, and another with dense vegetation including blueberry and heather. Findings indicate that the forest floor is a significant and substance-specific component of the ecosystem's VOC budget.

At the litter-dominated site, emissions were primarily driven by oxygenated VOCs, specifically acetaldehyde, methanol, and acetone. In contrast, the vegetation-rich site saw a higher prevalence of biogenic hydrocarbons, with isoprene fluxes reflecting the emission capacity of the dense undergrowth.