Project Details
Projekt
Budgeting Oxygen Generation under Changing Light Conditions in Oligotrophic Waters (O2-GLOW)
Applicant
Dr. Alexander Frank
Subject Area
Hydrogeology, Hydrology, Limnology, Urban Water Management, Water Chemistry, Integrated Water Resources Management
Term
since 2021
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 490946044
In order to understand metabolic responses of lake ecosystems to rapid environmental changes like browning, detailed quantification of primary production and respiration under natural conditions is indispensable. However, day time respiration is 'invisible' to traditional concentration measurements. Thus, our procedural understanding and qualities of predictions are limited. Stable isotope measurements of oxygen and carbon may offer a tool to investigate functional relationships during day time. We propose to use high-frequency in situ measurements together with long term ecosystem research, and stable isotopes to evaluate light-dependencies of natural phytoplankton communities in 3 different lakes, over the course of one year. Harnessing the power of these different methodologies, we expect to (a) determine the drivers of in situ day Respiration, (b) determine the variability of R in time, (c) evaluate the stability of community respiration fractionation, (d) estimate variability in photosynthetic quotients, and (e) quantify high-light-induced non-productive processes in the natural environment. Answering the above objectives and hypothesis will provide information on the relationship between lake metabolism and community composition, including unbiased estimates on daytime respiration. It will also provide knowledge on light-induced variability in photosynthetic quotients and the potential effects of high-light conditions on gross and net ecosystem production.In general, these investigations will further our understanding of oligotrophic and clear lake ecosystem metabolism and provide a solid foundation for exploring fundamental questions in lake ecology, including browning.
DFG Programme
Research Grants
International Connection
Italy, Sweden, United Kingdom
Co-Investigator
Professor Johannes Barth, Ph.D.
