Air collection and Gas flux measurements

Vienna Scientific Instruments designs and builds chambers and devices allowing to sample air and measure gas fluxes.

Gas exchange measurements (e.g. on greenhouse gases including CO2) are often made with the closed, non-steady state chamber technique whereby a chamber is placed on top of the soil for a short interval and the change in gas concentrations in the chamber headspace is monitored over time - either by continued measurements or sampling of gas aliquots from the chamber headspace. The resulting time series of gas concentration measurements makes it possible to estimate the surface–atmosphere exchange with the plot on which the chamber was installed. In open dynamic systems (=steady-state flow-through systems) fresh ambient air is pumped into or pulled from a chamber, and flux is calculated using the air flow rate and the difference in concentrations between the air entering and leaving the chamber after the air in the chamber headspace has reached a steady state.

Closed Ecosystem respiration chambers for CO2, GHG and O2 measurements of soil, plant systems in situ and laboratory
Open PTFE chambers for measurements of highly reactive substances such as volatiles (VOCs) or ozone
Automatic air sampling of chamber headspace or ambient air into evacuated vials

We are / were involved in several research projects aiming to develop automatic, UAV-based gas sampling technology ("Iso-Drone") allowing to measure isotope rates of greenhouse gases and water vapour to replace costly research infrastructure such as Eddy towers etc.

We are involved in a R&D project aiming to develop an automatic chamber system for automatic CO2 efflux measurements in situ.

Selected readings on Chamber based gas fluX MEASUREMENTS

Lüpke, M., R. Steinbrecher, M. Leuchner, and A. Menzel. 2017. The Tree Drought Emission MONitor (Tree DEMON), an innovative system for assessing biogenic volatile organic compounds emission from plants. Plant Methods 13:14.
Madsen, R., Xu, L, Mcdermitt D. 2010. Considerations for making chamber-based soil CO2 flux measurements. Pages 28-31 in Proceedings of the 19th World Congress of Soil Science: Soil solutions for a changing world, Brisbane, Australia, 1-6 August 2010. Congress Symposium 4: Greenhouse gases from soils. International Union of Soil Sciences (IUSS), c/o Institut für Bodenforschung, Universität für Bodenkultur.
Pumpanen, J., P. Kolari, H. Ilvesniemi, K. Minkkinen, T. Vesala, S. Niinisto, A. Lohila, T. Larmola, M. Morero, M. Pihlatie, I. Janssens, J. C. Yuste, J. M. Grnzweig, S. Reth, J. A. Subke, K. Savage, W. Kutsch, G. Ostreng, W. Ziegler, P. Anthoni, A. Lindroth, and P. Hari. 2004. Comparison of different chamber techniques for measuring soil CO2 efflux. Agricultural and Forest Meteorology 123:159-176.
Siegenthaler, A., B. Welch, S. R. Pangala, M. Peacock, and V. Gauci. 2016. Semi-rigid chambers for methane gas flux measurements on tree stems. Biogeosciences 13:1197.
Timkovsky, J., P. Gankema, R. Pierik, and R. Holzinger. 2014. A plant chamber system with downstream reaction chamber to study the effects of pollution on biogenic emissions. Environmental Science: Processes & Impacts 16:2301-2312.
Zhang, X., R. Schwantes, R. McVay, H. Lignell, M. Coggon, R. Flagan, and J. Seinfeld. 2015. Vapor wall deposition in Teflon chambers. Atmospheric Chemistry and Physics 15:4197-4214.