The terrestrial biosphere is a major source of natural Volatile Organic Compounds (VOCs). Plants produce a wide spectrum of Biogenic Volatile Organic Compounds (BVOCs) in various tissues above and below ground to communicate with other plants and organisms.
At present, about 1700 substances have been found to be emitted from plants. Nearly all organs from vegetative parts, as well as flowers and roots emit these compounds. Many BVOCs are emitted constitutively and the emissions can be observed throughout the life cycle of the plant or, more often, at specific developmental stages. The emission is biosynthetically controlled by abiotic factors such as light and/or temperature, atmospheric CO2 concentration, or nutrition. Other BVOCs are induced after wounding and herbivore feeding or after environmental stresses. Stresses may induce change of constitutive BVOCs, either stimulating or quenching the emissions or may induce de novo synthesis and emission of BVOCs.
Isoprene and monoterpenes dominate biogenic emissions but other reactive chemical species, such as methanol, acetone, aldehydes and organic acids, are now also recognized to be emitted by the terrestrial vegetation at significant levels. These biogenic compounds play a crucial role in tropospheric chemistry, from local to global scales, inducing increased or decreased ozone formation, depending on NOx levels.
A number of projects focus on the exchange of BVOCs, carbon dioxide and water between Alpine forests and the atmosphere, to improve the understanding of the chemical-hydrological coupling between the terrestrial biosphere and the atmosphere in the Alps. We have collaborations with the University of Natural Resources and Life Sciences in Vienna (BOKU), and the biometeorology group at the Institute for Ecology of the University of Innsbruck.
PhD students: Arianna Peron, Marcus Striednig, Judith Schmack
Collaborations: Dr. Georg Wohlfahrt (ecology @ UIBK), Dr. Hans Sanden (BOKU), Dr. Lisa Kaser (CIRES, USA), Dr. Alex Guenther (UC Irvine, USA), Dr. Jörg Schnitzler (HZ Munich, Germany)