Tree emissions of volatile compounds are complex and not fully understood
In our latest publication, we investigated with total hydroxyl radical (OH) reactivity measurements our understanding of emissions from three tree species found in the boreal forest. The unexplained fraction of the reactivity remain high in some circumstances. We recently published in Biogeosciences the results of our study from 2017, where we analysed the emissions from three different trees with gas chromatographic methods and total OH reactivity instrumentation. We analysed emissions at the branch level with enclosure for birch, spruce, and pine. Our findings are that emissions do vary in amount and composition throughout the growing season and we could show, based on reactivity measurements, that the emissions are not fully characterized chemically. In particular when trees were subject to stress (that was clearly visible with, for instance, browning leaves or needles) the reactivity of the emissions increased a lot and we observed simultaneously an increase of emissions of Green L