Articles | Volume 23, issue 17
https://doi.org/10.5194/bg-23-6317-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/bg-23-6317-2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
14 Sep 2026
Research article |
| 14 Sep 2026
| 14 Sep 2026
A boost on the final stretch: intense river metabolism and wetland discharge increase aquatic CO2 dynamics in the Danube Delta
Marie-Sophie Maier
Department of Surface Waters, Research and Management, Eawag, 6047 Kastanienbaum, Switzerland
Department of Environmental Systems Science, ETH Zurich, 8092 Zurich, Switzerland
Bernhard Wehrli
CORRESPONDING AUTHOR
Department of Surface Waters, Research and Management, Eawag, 6047 Kastanienbaum, Switzerland
Department of Environmental Systems Science, ETH Zurich, 8092 Zurich, Switzerland
Cristian R. Teodoru
National Research – Development Institute for Marine Geology and Geoecology (GeoEcoMar), Dimitrie Onciu Street 23–25, 024053 Bucharest, Romania
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Short summary
Monitoring stations in the Danube Delta revealed two orders of magnitude difference in the intensity of oxygen and carbon dioxide cycles. Biological processes were driving more intense day-night cycles in delta channels compared to river reaches and were mainly controlled by changes in temperature and cloud cover. Wetland discharge added dissolved CO2 from anaerobic processes and caused higher emission rates in delta channels and downstream river reaches.
Monitoring stations in the Danube Delta revealed two orders of magnitude difference in the...
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