Is it possible to measure CO2 effluxes in an arable ecosystem using chambers without soil frames?

0424052 - ÚVGZ 2014 RIV CZ eng C - Konferenční příspěvek (zahraniční konf.)
Juszczak, R. - Acosta, Manuel - Sakowska, K. - Leśny, J. - Uździcka, B. - Chojnicki, B. H. - Urbaniak, M. - Olejnik, Janusz
Is it possible to measure CO2 effluxes in an arable ecosystem using chambers without soil frames?
Global Change and Resilience: From Impacts to Responses : Proceedings of the 3rd annual Global Change and Resilience Conference. Brno: Global change research centre, Academy of Sciences of the Czech Republic, v. v. i, 2013 - (Stojanov, R.; Žalud, Z.; Cudlín, P.; Farda, A.; Urban, O.; Trnka, M.), s. 168-172. ISBN 978-80-904351-8-6.
[Global Change and Resilience. Brno (CZ), 22.05.2013-24.05.2013]
Institucionální podpora: RVO:67179843
Klíčová slova: dynamic chamber * CO2 effluxes * chamber seal * push-in chamber
Kód oboru RIV: EH - Ekologie - společenstva

The push-in chamber and chambers with alternative gaskets were tested under fi eld conditions in order to estimate the rates of under- or overestimation of the CO2 effl uxes measured with chambers placed directly on a soil surface (without collars). Th e experiment was conducted on a spring barley fi eld which was harvested just before the measuring campaign. Th e following were tested: 1) a pushed-in chamber with a sharp metal blade installed on the edge of the chamber walls which was inserted to a depth of 1–2 cm to the soil, 2) a chamber with a 10 cm wide and 3 cm high rubber gasket, and 3) a chamber with a 10 cm wide and 2 cm high neoprene gasket. Th e results indicated that the application of the pushed-in chamber led to overestimation of the fl uxes by 55%, while application of chambers with alternative gaskets led to underestimation of the fl uxes by 30–40% due to the leakage of the gas from the chamber headspace through holes beneath the gaskets. Our experiment confi rmed that soil frames should be applied in fi eld conditions to assure the tightness of the chambers. Other tested solutions increase the biases of the chamber measurements and increase the uncertainties of the estimated CO2 effl uxes.
Trvalý link: http://hdl.handle.net/11104/0230128