Development of data assimilation techniques for reactive transport processes: real-time prediction of nitrate migration in porous media (DFG Research Project)
Figure 1. Nitrate degradation in aquifers
Nitrate is a major contaminant in many aquifers due to massive use of fertilizers in agriculture and wastewater discharge into streams. Nitrate reaches the groundwater either by infiltration through soils, by surface runoff into streams and lakes or migration through the hyporheic zone.
Reduction of nitrate by denitrification is the only way for natural nitrate removal from groundwater as no further nitrate sinks, such as insoluble nitrate minerals, exist and nitrate sorption does not occur. As high nitrate concentrations in groundwater affect the quality of drinking water, prediction and monitoring of the nitrate migration is essential to protect and maintain our drinking water resources. However, up to now smart monitoring concepts are missing that can forecast the migration of the nitrate and the development of the degradation potential due to the availability of the electron donors, such as pyrite or/and organic matter.
This project aims on the first application of the Ensemble Kalman filter on a reactive transport problem to provide a real-time forecast of nitrate degradation in shallow aquifers. For this goal laboratory experiments are designed to investigate under high controlled conditions and well-defined boundary conditions heterotrophic and autolithotrophic nitrate reduction.
Existing data assimilation techniques used to monitor the real-time migration of conservative solutes are adapted from these conservative transport processes and to reactive transport processes.
Figure 2. Laboratory experiments for highly controlled observation of nitrate degradation in porous media
Prof. Dr. Martin Kaupenjohann, Department of Soil Science, TU Berlin
International project partners
Prof. Dr. Monica Riva, Department of Civil and Environmental Engineering, Politecnico di Milano, Italy
Prof. Dr. Alberto Guadagnini, Department of Civil and Environmental Engineering, Politecnico di Milano, Italy
Dr. Glenn Hammond, Pacific Northwest National Laboratory, U.S.A.
The project is funded by the Deutsche Forschungsgemeinschaft (DFG).
Funding period: 2021-2024