Emission of Fire-Promoting Volatiles from Picea omorika (Pančić) Purk Needles in Different Forest Communities

The importance of studying the role of volatiles in flammability is well recognized, but the relationship between specific compounds and components of flammability is underestimated. In this study, volatiles emitted from Picea omorika (Pančić) Purk. needles were identified and quantified, and the relationship between volatile emission and moisture content, flammability characteristics and bioclimatic coefficients was investigated. Fresh needles from four different forest communities were analyzed for specific volatile organic compounds (using a gas chromatography-surface acoustic wave analyzer, GC-SAW), moisture content (based on fresh and oven-dried mass), and flammability components (using an epiradiator). Five monoterpenes, one sesquiterpene, and one alcohol were identified and their amounts, moisture content, and flammability components differed between the populations. The amounts of myrcene and β-pinene correlated significantly with moisture content and time to ignition. Myrcene content also correlated with flame duration, site altitude, mean annual temperature, variation in mean annual temperature, and the Ellenberg quotient. The emission of myrcene correlates with ecophysiological, flammability, topographic, and climatic variables. This suggests that myrcene-rich plant species may be of particular interest for research into flammability, especially from the point of view of rapid ignition.