Jan Köhler

Dr. Jan Köhler is a Research Group Leader and Head of Department (ad interim) at the Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) in Berlin, Germany, where he leads Department 2: Community and Ecosystem Ecology. With over three decades of experience since joining IGB as a senior scientist in 1992, Köhler has established himself as a leading expert in freshwater ecosystems, particularly focusing on phytoplankton dynamics, aquatic macrophytes, and ecosystem responses to environmental changes.

His research interests span freshwater ecology, plankton ecology, ecophysiology of algae, bistability of shallow lakes and lowland rivers, and sustainable management of inland waters. Köhler's expertise is particularly evident in his work on phytoplankton growth responses to light fluctuations, macrophyte dynamics, and ecosystem responses to human impacts, as demonstrated by his extensive publication record spanning from 1992 to projected 2025 publications.

Köhler's recent research has focused on critical environmental issues including the Oder River environmental disaster of 2022, harmful algal blooms (particularly Prymnesium parvum), and the complex interactions between nutrient loading, light conditions, and aquatic ecosystem structure. His work combines field studies, experimental approaches, and modeling to understand ecosystem dynamics across multiple temporal and spatial scales.

Among his notable scientific contributions are publications examining phytoplankton community shifts following storm events, the genetic basis of fish-killing toxins in algae, and the socio-ecological dimensions of aquatic plant management. His research demonstrates a consistent pattern of addressing both fundamental ecological questions and applied management challenges in freshwater systems.

• Award of the German Academy of Natural Scientists (1994)

Köhler has led and participated in numerous significant research projects including the ODER~SO program investigating the 2022 Oder River environmental disaster (2023-2026), the MadMacs project on aquatic macrophyte management (2019-2022), and the Sino-German SIGN project focused on water quality improvement in China's Taihu region (2015-2018). His collaborative approach is evident in his extensive co-authorship network spanning multiple countries and disciplines.

His laboratory and research group focus on Photosynthesis and Growth of Phytoplankton and Macrophytes, with particular attention to how these organisms respond to changing environmental conditions including light availability, nutrient concentrations, and human disturbances. This research has direct implications for understanding and managing freshwater ecosystems in the face of global environmental change.