Biogenic volatile organic compound emissions from Scots pine seedlings under prolonged heat and drought
Authors: Molteni Ugo , Bose Arun , Faiola Celia , Gisler Jonan , Gu Shan , Hunziker Stefan , Kalberer Markus , Luo Na , Nazarova Tatiana , Pieber Simone Maria , Gessler Arthur 
Published: February 2023

Biogenic volatile organic compounds (BVOCs) comprise the largest, most highly complex, and diverse fraction of the volatile organic compounds (VOCs) emitted into the atmosphere (Sindelarova et al., 2014). By emitting BVOCs, plants communicate, fight herbivores and attract pollinators (Niinemets and Monson, 2013). Atmospheric oxidation of BVOCs affects the concentration of methane, carbon monoxide, and tropospheric ozone and leads to the formation of Secondary Organic Aerosol (SOA). Atmospheric aerosol load plays a crucial role in defining the radiative balance and negatively impacts air-quality standards (Seinfeld, John H. and Pandis, Spyros N., 2016).&#160;Climate models project an increase in the average global temperature for the next decades, with Alpine regions expected to be over-proportionally more affected. Drought, heat, and insects feeding on plants cause stress in the organism, which the organism reacts to by changing the BVOCs emissions: certain compounds can be promoted, and others reduced. This may lead to subsequent changes in atmospheric chemistry and SOA properties depending on the cause of stress and the plant&#8217;s reaction (Smith et al., 2021).&#160;Within the experimental project "Acclimation and environmental memory&#8221; in 2022, we studied the impact of prolonged heat and drought on BVOC emission from Scots pine (Pinus Sylvestris) seedlings. Seedlings were grown from seeds collected from selected mother trees from the long-term irrigation experiment Pfynwald, with different long-term water availability. This allowed us also to examine the additional consequence of transgenerational memory on BVOC emissions (Bose et al., 2020). Our results combine data from samples collected on sorbent tubes and analyzed by Thermal Desorption GC-MS with online BVOC measurements using&#160; PTR-ToF-MS and provide a well-resolved picture of terpene compositions as well as diurnal trends in emission levels.&#160;Bibliography&#160;Bose, A. K., Moser, B., Rigling, A., Lehmann, M. M., Milcu, A., Peter, M., Rellstab, C., Wohlgemuth, T., and Gessler, A.: Memory of environmental conditions across generations affects the acclimation potential of scots pine, Plant Cell Environ., 43, 1288&#8211;1299, https://doi.org/10.1111/pce.13729, 2020.Niinemets, &#220;. and Monson, R. K. (Eds.): Biology, Controls and Models of Tree Volatile Organic Compound Emissions, Springer Netherlands, Dordrecht, https://doi.org/10.1007/978-94-007-6606-8, 2013.Seinfeld, John H. and Pandis, Spyros N.: Atmospheric Chemistry and Physics: From Air Pollution to Climate Change, 3rd Edition., Wiley, 1152 pp., 2016.Sindelarova, K., Granier, C., Bouarar, I., Guenther, A., Tilmes, S., Stavrakou, T., M&#252;ller, J.-F., Kuhn, U., Stefani, P., and Knorr, W.: Global data set of biogenic VOC emissions calculated by the MEGAN model over the last 30 years, Atmospheric Chem. Phys., 14, 9317&#8211;9341, https://doi.org/10.5194/acp-14-9317-2014, 2014.Smith, N. R., Crescenzo, G. V., Huang, Y., Hettiyadura, A. P. S., Siemens, K., Li, Y., Faiola, C. L., Laskin, A., Shiraiwa, M., Bertram, A. K., and Nizkorodov, S. A.: Viscosity and liquid&#8211;liquid phase separation in healthy and stressed plant SOA, Environ. Sci. Atmospheres, 1, 140&#8211;153, https://doi.org/10.1039/D0EA00020E, 2021.