In the last decades, several technologies have been developed to measure greenhouse gas (GHG) concentrations and fluxes. We compared six devices using different measurement technologies: two gas chromatographic systems with a barrier discharge ionization detector (GC-BID) and an electron capture detector (GC-ECD), respectively, a portable GHG analyzer based on laser absorption, a photoacoustic field gas analyzer, and two portable Fourier transform infra-red (FTIR) devices. Absolute concentration measurements agreed well between the non-GC devices for carbon dioxide (CO2), nitrous oxide (N2O) and methane (CH4). CO2 flux measurements under laboratory conditions showed acceptable agreement between the measurement systems. Observed deviations in fluxes were attributed to methodical susceptibilities of chamber measurements rather than to erroneous concentration measurements. We conclude that the less often used photoacoustic and FTIR devices are suitable for studies of GHG fluxes and represent a useful alternative to currently used techniques in the field thanks to their portable character.
Key words: GHG, gas chromatography, laser absorption, photoacoustic analyzer, FTIR