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Liepolt Award

I am happy to announce that I was awarded the Reinhard Liepolt Prize for my Ph.D. thesis, "Restoring flows in modified rivers".

The Liepolt Prize is given every two years by the Austrian Committee for Danube Research of the International Community for Danube Research (ÖK-IAD) and recognizes special achievements in the field of limnologically relevant research related to the Austrian Danube River Basin. The Liepolt Prize 2021 was awarded to four young scientists: Dr. Thomas Friedrich, Dr. Daniel S. Hayes, Dr. Matthias Pucher, and Dr. Lukas Zangl.

Winners of the 2021 Liepolt Prize: Dr. Daniel Hayes (left) and Dr. Thomas Friedrich (second from left), together with ÖK-IAD members and Veronika Koller-Kreimel, who received the honorary award.
Award Ceremony Foto (© Gertrud Haidvogl)

In my dissertation, I investigated hydro-ecological relationships to develop criteria for better hydropower plant management, which should contribute to improving ecology in rivers affected by water abstraction and hydropeaking.

The individual papers of this cumulative dissertation are based on analyses of extensive databases on the national scale (Austria) and literature synthesis. For example, I analyzed the ecological effects of multiple stressors and found that hydrological regulation is a major stressor for grayling populations in hyporhithral rivers. By linking ecological processes to the flow of different temporal resolutions (annual, seasonal, daily), I was also able to develop basic principles, qualitative criteria, and quantitative thresholds for implementing hydrological restoration measures. Overall, this practice-relevant thesis contributes to define guidelines for the legally required ecological improvement of rivers affected by power plants - for Austria, the Danube region, and beyond.

My dissertation, which was completed in 2021 at the University of Lisbon in cooperation with the University of Natural Resources and Applied Life Sciences, Vienna (BOKU), consists of the following four core publications (as well as an additional five papers that were written during this time but are listed in the thesis appendix due to a different topic focus):

  • Hayes, D.S., Lautsch, E., Unfer, G., Greimel, F., Zeiringer, B., Höller, N., & Schmutz, S. (2021). Response of European grayling, Thymallus thymallus, to multiple stressors in hydropeaking rivers. Journal of Environmental Management, 292, 112737. doi: 10.1016/j.jenvman.2021.112737 ☞ download PDF

  • Hayes, D.S., Brändle, J.M., Seliger, C., Zeiringer, B., Ferreira, T., & Schmutz, S. (2018). Advancing towards functional environmental flows for temperate floodplain rivers. Science of the Total Environment, 633, 1089–1104. doi: 10.1016/j.scitotenv.2018.03.221 ☞ download PDF

  • Hayes, D.S., Moreira, M., Boavida, I., Haslauer, M., Unfer, G., Zeiringer, B., Greimel, F., Auer, S., Ferreira, T., & Schmutz, S. (2019). Life Stage-Specific Hydropeaking Flow Rules. Sustainability, 11(6), 1547. doi: 10.3390/su11061547 ☞ download PDF

  • Moreira, M., Hayes, D.S., Boavida, I., Schletterer, M., Schmutz, S., & Pinheiro, A. (2019). Ecologically-based criteria for hydropeaking mitigation: A review. Science of the Total Environment, 657, 1508-1522. doi: 10.1016/j.scitotenv.2018.12.107 ☞ download PDF

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