Pollutant Turnover in the Groundwater - Stream Transition Zone of Contrasting Lower-Order Sub-Catchments (P02)

• Subject Area: Hydrogeology, Hydrology, Limnology, Urban Water Management, Water Chemistry, Integrated Water Resources Management
• Term: from 2017 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 281741268

Results from the first phase of CAMPOS revealed that concentrations of nitrate in the stream and the near-stream aquifer are dominantly controlled by an interplay between bidirectional groundwater-stream exchange and concomitant reactive turnover along exchange flow paths. We will quantify the relative contributions of hydrologic versus reactive processes to nitrate concentration variability in lower-order streams and their connected aquifers. Patterns of groundwater-stream exchange will be simulated, while reactive turnover will be investigated using an innovative combination of field measurements, in-situ mesocosms, functional microbiome analyses and sensitive 15N isotope analysis of reactive N-species. Patterns and dynamics of reactivity and turnover in riparian groundwater will be quantified with reactive transport and dual isotope models.

• DFG Programme: Collaborative Research Centres
• Subproject of: SFB 1253: Catchments as Reactors: Metabolism of Pollutants on the Landscape Scale (CAMPOS)
• Applicant Institution: Eberhard Karls Universität Tübingen
• Project Heads: Professor Dr. Martin Elsner; Professor Dr. Jan Fleckenstein; Professor Dr. Tillmann Lüders; Dr. Marc Schwientek