University of Natural Resources and Life Sciences, Vienna (BOKU) - Research portal
Gewählte Master / Diploma Thesis:
Eva Katharina Ecker
(2019):
Trace gas emissions upon drying-rewetting of grassland and forest soils.
Master / Diploma Thesis - Institut für Bodenforschung (IBF),
BOKU-Universität für Bodenkultur,
pp 55.
UB BOKU
obvsg
- Abstract:
- Climate change influences climate parameters not only at the annual scale; extreme weather events, like droughts and episodic rainfall are expected to be altered in the future. Abrupt changes in environmental conditions will likely affect microbial-driven processes in the soil, thus influencing carbon and nitrogen turnover and the net exchange of greenhouse gases (GHG) between the soil and the atmosphere. Since soils take up and release large amounts of GHG, it is highly important to gain a deeper understanding on the connection between extreme weather events and the production and consumption of trace gases in the soil. While some studies have addressed effects on carbon dioxide (CO2) emissions, consequences of extreme weather events on nitric oxide (NO and further NOx), nitrous oxide (N2O) and methane (CH4) emissions are hardly described so far. The aim of the study was to investigate how land uses differ in terms of soil gas fluxes and how varying re-wetting treatments effect trace gas fluxes. To dissect these issues, a laboratory incubation was conducted, with four varying re-wetting intensities on intact mineral soil cores and organic material from a forest in the Rosalian mountains and mineral soil samples from a grassland site (pre-Alps region Gumpenstein) in Austria. The samples, incubated in dry conditions and then subjected to re-wetting, were monitored for CO2, NO, NOx, N2O and CH4 during the whole incubation period at sub-daily resolution. The mineral soil samples showed higher CO2 fluxes in the grassland site than in the forest one. The highest NO emissions occurred at low moisture levels (25%); maximum CO2 emissions and CH4 uptake levels were observed at intermediate soil moisture (50-75%), N2O emissions increased significantly at values near soil saturation (75-100% WHC). Maximum soil N2O fluxes from the grassland were one order of magnitude higher than in the forest, probably due to the higher nitrogen availability through regular fertilization.
- Beurteilende(r): Zechmeister-Boltenstern Sophie
- 1.Mitwirkender: Diaz-Pines Eugenio