Consequences of intense drought on CO2 and CH4 fluxes of the reed ecosystem at Lake Neusiedl.
- Author(s)
- Pamela Alessandra Baur, Andreas Maier, Claudia Buchsteiner, Thomas Zechmeister, Stephan Glatzel
- Abstract
Reed (Phragmites australis) dominated wetlands are commonly known as strong carbon (C) sinks due to the high productivity of the reed plant and C fixation in the wetland soil. However, little is known about the effects of drought on reed-dominated wetlands and the possibility of Pannonian reed ecosystems being a source of greenhouse gases (GHG). The drought at Lake Neusiedl had a particular impact on the water level, but also had consequences for the reed belt. Therefore, we investigated the drought-influenced C fluxes and their drivers in the reed ecosystem of this subsaline lake over a period of 4.5 years (mid-2018 to 2022). We applied eddy covariance technique to continuously quantify the vertical turbulent GHG exchange between reed belt & atmosphere and usedvegetation indices to account for reed growth. Methane emissions decreased by 76% from 9.2 g CH 4-C m -2a -1 (2019) to 2.2 g CH 4-C m -2 a -1 (2022), which can be explained by the falling water level, the associated drying out of the reed belt and its consequences. Carbon dioxide emissions initially decreased by 85% from 181 g CO 2-C m -2 a -1 (2019) to 27 g CO 2-C m -2 a -1 (2021), but then increased to twice the 2019 level in 2022 (391 g CO 2-C m -2 a -1). Due to the drying reed belt, the reed initially grew into formerly water-covered areas within the reed belt, especially in 2021, leading to higher photosynthesis through 2021. This development stopped and even reversed in 2022 as a consequence of the sharp decrease in sediment water content from about 65 to 32 Vol-% in mid-2022. Overall, drought led to a decoupling of the reed ecosystem from the open lake area and developed the wetland into a strong C source.
- Organisation(s)
- Department of Geography and Regional Research
- External organisation(s)
- Biological Station Lake Neusiedl
- Journal
- Environmental Research
- Volume
- 262
- ISSN
- 0013-9351
- DOI
- https://doi.org/10.1016/j.envres.2024.119907
- Publication date
- 12-2024
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 105205 Climate change, 106026 Ecosystem research, 105904 Environmental research, 105405 Geoecology
- Keywords
- ASJC Scopus subject areas
- Environmental Science(all), Biochemistry
- Sustainable Development Goals
- SDG 14 - Life Below Water, SDG 15 - Life on Land, SDG 13 - Climate Action
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/consequences-of-intense-drought-on-co2-and-ch4-fluxes-of-the-reed-ecosystem-at-lake-neusiedl(6f1fa8f0-ce0b-4895-933e-090a597fa82e).html