Abteilung Oberflächengewässer

Oberflächengewässer - Forschung & Management (Surf)

Wir untersuchen sowohl einzelne Prozesse in aquatischen Systemen als auch ganze Systeme natürlicher Gewässer.
Neben der Grundlagenforschung und der interdisziplinären Systemanalyse stehen anwendungsnahe Projekte besonders im Fokus.

Erfahren Sie mehr

News

Corona-Lockdowns: Seen wurden weltweit klarer

Satellitenbild vom Govind Ballabh Pant Sagar, dem grössten künstliche See Indiens. (Bild: europäischen Erdbeobachtungsprogramms Copernicus Global Land Service)
9. April 2026 –

Während der COVID-19-Pandemie stand die Welt still – und viele Seen wurden messbar klarer. Eine globale Studie zeigt: Die Lockdowns mit weniger Industrie, Verkehr und Freizeitaktivitäten liessen die Wassertrübung in Seen weltweit...

Während der COVID-19-Pandemie stand die Welt still – und viele Seen wurden messbar klarer. Eine globale Studie zeigt: Die Lockdowns mit weniger Industrie, Verkehr und Freizeitaktivitäten liessen die Wassertrübung in Seen weltweit abrupt sinken, vor allem in Uferregionen und Flussmündungen.
Weiterlesen

Weitere News

Neuste Publikationen

Amadori, M., Rahaghi, A. I., Bouffard, D., & Toffolon, M. (2025). Using automatic calibration to improve the physics behind complex numerical models: an example from a 3D lake model using Delft3D (v6.02.10) and DYNO-PODS (v1.0). Geoscientific Model Development, 18(11), 3473-3486. doi:10.5194/gmd-18-3473-2025, Institutional Repository

Models are simplified descriptions of reality and are intrinsically limited by the assumptions that have been introduced in their formulation. With the development of automatic calibration toolboxes, finding optimal parameters that suit the environmental system has become more convenient. Here, we explore how optimization toolboxes can be applied innovatively to uncover flaws in the physical formulations of models. We illustrate this approach by evaluating the effect of simplifications embedded in the formulation of a widely used hydro-thermodynamic model. We calibrate a Delft3D model based on temperature profiles for a case study, Lake Morat (Switzerland), through the DYNO-PODS optimization tool. The results show that higher values of the light extinction coefficient can compensate for neglecting the fraction β of short-wave radiation absorbed at the surface of the water. This leads to unrealistic values of the light extinction coefficient, as the optimization pushes its value toward the limit of no transparency, consistent with the need to reproduce a significant absorption at the surface. Although it is well known that β is significantly larger than zero, its absence from the model was never noticed as critical. Automatic calibration tools provide valuable diagnostic insights into the physical robustness of models, enabling more precise evaluation of their structural integrity and performance.
Twining, C. W., Blanco, A., Dutton, C., Kainz, M. J., Harvey, E., Kowarik, C., … Subalusky, A. L. (2025). Integrating the bright and dark sides of aquatic resource subsidies - a synthesis. Ecology Letters, 28(4), e70109 (20 pp.). doi:10.1111/ele.70109, Institutional Repository

Aquatic and terrestrial ecosystems are linked through the reciprocal exchange of materials and organisms. Aquatic-to-terrestrial subsidies are relatively small in most terrestrial ecosystems, but they can provide high contents of limiting resources that increase consumer fitness and ecosystem production. However, they also may carry significant contaminant loads, particularly in anthropogenically impacted watersheds. Global change processes, including land use change, climate change and biodiversity declines, are altering the quantity and quality of aquatic subsidies, potentially shifting the balance of costs and benefits of aquatic subsidies for terrestrial consumers. Many global change processes interact and impact both the bright and dark sides of aquatic subsidies simultaneously, highlighting the need for future integrative research that bridges ecosystem as well as disciplinary boundaries. We identify key research priorities, including increased quantification of the spatiotemporal variability in aquatic subsidies across a range of ecosystems, greater understanding of the landscape-scale extent of aquatic subsidy impacts and deeper exploration of the relative costs and benefits of aquatic subsidies for consumers.
Storelli, N., Sepúlveda Steiner, O., Di Nezio, F., Roman, S., Buetti-Dinh, A., & Bouffard, D. (2025). Physically stable yet biologically sensitive: multiyear ecological dynamics of anoxygenic phototrophs in stably redox-stratified Lake Cadagno. Aquatic Sciences, 87(2), 58 (12 pp.). doi:10.1007/s00027-025-01183-1, Institutional Repository

Lake Cadagno is a meromictic alpine lake characterized by permanent stratification, which creates a permanent anoxic environment that supports the growth of anoxygenic phototrophic sulfur bacteria. The seasonality and interseasonality of these microorganisms were examined over a three-year period (2019–2021) through regular monitoring of the water column. A variety of physical–chemical parameters, including temperature, conductivity, light, oxygen and sulfide concentrations, and the community composition of anoxygenic phototrophic sulfur bacteria in the chemocline were recorded, to observe potential influence of external weather conditions. Our findings indicate that, despite the lake’s consistent physical and chemical stratification, the composition of the anoxygenic phototrophic sulfur bacteria community exhibited notable variations in response to external environmental factors, including changes in rainfall and light irradiance. Specifically, we observed different growth dynamics in the purple (PSB) and green (GSB) sulfur bacteria communities over the three years of monitoring. These variations underscore the complexity of biogeochemical cycles in meromictic lakes and the impact of external environmental factors on this ancestral microbial community dynamics. The results provide valuable insights into the stability of redox-stratified environments, offering a modern analog for ancient aquatic ecosystems. This research emphasizes the importance of long-term regular monitoring to capture interannual dynamics and assess the implications of climate change on such unique ecosystems.

Surf Seminare

Weitere
16. - 21.08.​2026,
9:00 Uhr
Lausanne
Symposium on Ecohydraulics 2026

ISE 2026 + Swiss Ecohydraulics day

08.09.​2026,
9:00 Uhr
Verkehrshaus Luzern
Eawag-Infotag 2026: Energie - Wasser - Zukunft

Infotag 2026

Weitere

Graduate Studies in unserer Abteilung

Video über Graduate Studies in der Abteilung Oberflächengewässer

Video über Graduate Studies in unserer Abteilung

Forschungsprojekte

In den kommenden 80 Jahren werden in der Schweiz 4‘000km Fliessgewässer revitalisiert – eine einmalige Chance für einen Lernprozess!

Wirkungskontrolle bei Flussrevitalisierungen
Die Veränderung des Klimas wirkt sich auch auf die Seen aus. Wir untersuchen die Zusammenhänge in diesem komplexen System mit der Analyse von globale Daten und mit lokalen Fallstudien.

Klimawandel und Seen
Une nouvelle plateforme de recherche multidisciplinaire pour le lac Léman.

Lac Léman Exploration
Mikroben können Metalle "atmen", und Metalle können auch als Aufzeichnungen über die Vergangenheit der Erde dienen. In diesem Projekt werden diese Funktionen von Metallen in anoxischen Seen untersucht.

Biogeochemischer Kreislauf an oxisch-anoxischen Grenzen
We try to understand the bulk and compound specific carbon and nitrogen isotopic compositions in food chains.

Ecology of food chain in freshwater systems
Abwasser ist mit antibiotikaresistenten Bakterien belastet. Wir untersuchen ihre Ausbreitung in die Umwelt und Gegenmassnahmen.

Antibiotikaresistenzen als Umweltkontamination
IsoTalk - Dynamik der Isochrysidales Blüte in Schweizer Seen: Auf dem Weg zu einem Alkenone-Paläothermometer für Seen in den mittleren Breiten.

Dynamik der Isochrysidales Blüte in Schweizer Seen
Wie kann die Erdbeobachtung genutzt werden, um die Handlungsspielräume der Wasserwirtschaft im Klimawandel abzuschätzen.

Sichere Optionen im Management von Wasserressourcen

Weitere aktuelle Forschungsprojekte