Fluxflood Project Fieldwork Update – Donau-Auen National Park

This week, we returned to our research sites in Donau-Auen National Park alongside Nadija Čehajić (BOKU University), who collected water samples as part of the DANUBIUS project. From our side, we focused on maintaining and verifying the performance of our automated flux chambers that continuously monitor CO₂ and CH₄ aquatic fluxes from floodplain.

Unfortunately, fieldwork rarely comes without challenges—one chamber was flooded and damaged. Thankfully, a replacement is already underway. The remaining chambers are fully operational, delivering high-frequency (hourly) flux data.

Environmental conditions remain unusual for this time of year: water levels are still exceptionally low, yet primary production is high, and we’re observing elevated CH₄ concentrations in surface waters—highlighting the complex biogeochemical dynamics during low-flow periods.

During sampling, we encountered a viper basking in the sun near one of our chambers , and were briefly accompanied by a striking butterfly—nature never fails to surprise!

In addition to gas flux measurements, we collected water samples to analyze CH₄ and CO₂ concentrations. Laboratory work followed, using Picarro isotopic analyzer, which provided not only gas concentrations but also stable isotope signatures. These data are crucial for understanding the role of groundwater inputs in modulating surface water GHG concentrations in floodplain systems.

All in all, it was a productive week in the field and lab—generating a valuable dataset that will contribute to an exciting manuscript.