Aquatic Ecology
Aquatic ecology generally studies communities of organisms, processes, and interactions in freshwater and marine systems, as well as their responses to environmental change.
Research
© Maria Stockenreiter
The Aquatic Ecology research group works with the aim of gaining a better understanding of the structure, dynamics, and functioning of pelagic food webs in freshwater and marine systems. Central to its research is the question of how biotic interactions and abiotic environmental factors—such as temperature, nutrient availability, and species-specific traits—influence the composition and performance of plankton communities. The group investigates both primary producers (e.g. phytoplankton) and consumers (e.g. zooplankton), as well as their interactions.
Current projects:
Trait-based direction of density-dependent effects in freshwater host–endosymbiont systems (TREND) DynaSym DFG Forschergruppe
Interactions between temperature-driven changes in zooplankton metabolic demand and resource quality, and their consequences for trophic dynamics and food-web structure (PlanktoDYN) DFG
Phytoplankton blooms “like it colorful” – the relative influence of biodiversity and biotic interactions on early stages of phytoplankton blooms (BLIC) DFG - ANR
Genetic and ecological characterization of the invasive freshwater jellyfish Craspedacusta sowerbii DFG
AQUACOSM-plus: Network of Leading Ecosystem-Scale Experimental Aquatic Mesocosm Facilities Connecting Rivers, Lakes, Estuaries, and Oceans in Europe and beyond
Approach
© CAROLIN BLEESE
In aquatic ecology, both experimental field studies and laboratory investigations of aquatic food webs are conducted in order to systematically test ecological hypotheses. A central tool is mesocosm experiments, in which controllable water columns are deployed in lakes to analyze the effects of factors such as light intensity, temperature, nutrient availability, or food web structure on biological communities. Chemical and physical probes are used to measure water quality parameters. In addition, laboratory instruments such as spectrophotometers, fluorometers, and discrete analyzers are employed to analyze water chemistry and plankton composition.
Fluorescence-based methods, such as PAM fluorescence measurements, enable the determination of the photosynthetic activity of phytoplankton, while stable isotope analyses are used to quantify trophic pathways and energy flows within food webs. Microscopic cell counts and cell analyses are applied to investigate the population dynamics of plankton and other organisms.
Furthermore, experimental results are often complemented by theoretical modeling, for example to analyze the early stages of phytoplankton blooms. Finally, laboratory and field data are compared in order to gain a comprehensive understanding of ecological processes under natural conditions and to identify relationships between environmental factors and biological communities.
Jellyfish sighting
© CAROLIN BLEESE
Have you seen jellyfish in a lake?
We are looking for lakes where freshwater jellyfish occur and would be happy to receive any reports of sightings.
Contact: Stefan Dehos
Latest publications
Pondaven, P., Stibor, H., Huang ,Y-T., Stockenreiter, M. , Behl , S., Stieglitz, T. , Patris , S.and Ucharm, G. (2026). Photophysiological Performance of Zooxanthellate Endosymbionts (Symbiodiniaceae) in the Golden Jellyfish Mastigias papua Across a Natural Environmental Gradient in Marine Lakes of Palau (Micronesia)
Front. Photobiol. - Photoecology and Environmental Photobiology, accepted
Schachtl, K., Gießler, S., Stockenreiter, M., & Stibor, H. (2026). Top-down effects of the freshwater jellyfish Craspedacusta sowerbii: an experimental approach. Journal of Plankton Research, 48(1), https://doi.org/10.1093/plankt/fbag001
Ilic, M., Brehm, S., Stockenreiter, M., von Elert, E., Fink, P. (2026). Essential dietary fatty acids affect intraspecific competition in herbivorous zooplankton. Limnology & Oceanography 10.1002/lno.70321
Nicoară, M., Niculea, A., Hegedűs, A., Briddon, C. L., Stockenreiter, M., Stibor, H., ... & Drugă, B. (2025). Adaptation to warming alters the competition between three phytoplankton taxa: Microcystis aeruginosa, Desmodesmus armatus and Mayamaea permitis. Community Ecology, 1-13. https://doi.org/10.1007/s42974-025-00284-z
Vogelmann, C., Schock, C., Feilhauer, M., Stibor, H., Schubert M. (2025). Automatic fish scale analysis: age determination, annuli and circuli detection, length and weight back-calculation of coregonid scales. Ecological Informatics 92, https://doi.org/10.1016/j.ecoinf.2025.103517.
Vogelmann, C., M. Teichert, M. Schubert, N. Dingemanse, and H. Stibor (2025). Reconstructing History: Scale Analysis Reveals Long-Term Changes in Age-Related Growth of a Coregonid Fish. Ecology and Evolution 15, e71884. https://doi.org/10.1002/ece3.71884.
Lüskow, F. B, Polgári, B., Stibor, H., Schachtl K., Abonyi, A. (2025). Light increases surface occurrence of the freshwater jellyfish Craspedacusta sowerbii via positive phototaxis. Hydrobiologia, https://doi.org/10.1007/s10750-025-05955-6
Stockenreiter, M.; Hammerstein, S.; Ilić, M.; Titocci, J.; Fink, P.; Stibor, H. (2025) Mesocosm studies linking phytoplankton diversity and zooplankton nutrition: the role of essential fatty acids in complex natural communities. Limnology and Oceanography, https://doi.org/10.1002/lno.70252
Meunier, C.; Schmidt, J.; Ahme, A.; Balkoni, A.; Berg, K.; Blum, L.; Boersma, M.; Brüwer, J.D.; Fuchs, B.M.; Gimenez, L.; Guignard, M.; Schulte-Hillen, R.; Krock, B.; Rick, J.; Stibor, H.; Stockenreiter, M.; Tulatz, S.; Weber, F.; Wichels, A.; Wiltshire, K.H.; Wohlrab, S.; Kirstein, I.V. (2025). Plankton communities today and tomorrow – potential impacts of multiple global change drivers and marine heatwaves. Limnology and Oceanography, https://doi.org/10.1002/lno.70042
Stockenreiter, M. (2025) Stay connected to be diverse! Global Change Biology, https://doi.org/10.1111/gcb.70046
