Department of Geoscience

Development of Reactive-Transport Models of Nitrogen Cycling Informed by Molecular-Biological Data

PhD Researcher: Anna Störiko
Supervisors: Olaf Cirpka (University of Tübingen), Holger Pagel (University of Hohenheim), Philippe van Capellen (University of Waterloo)

Microorganisms play a substantial role in the turn-over of nitrogen compounds like nitrate in the subsurface. Reactive transport models are an important tool for understanding and predicting fate and transport of nitrogen compounds. However, most current models either completely lack an appropriate representation of microbial dynamics. Or they simulate a generic biomass which is difficult to relate to measured quantities and does not differentiate between organisms with different functions.

Molecular biological data can provide quantitative information about organisms related to a specific reaction. Functional genes code for enzymes responsible for a certain reaction step for example in denitrification. Their concentrations can be seen as a proxy for the abundance of organisms with that function. More and more molecular biological data are collected in the field. However, we can currently not use it in a quantitative manner in reactive transport models since the models do not simulate these quantities.

The goal of my project is to develop a reactive transport model for the nitrogen cycle which can be informed by molecular biological data. In the first phase I develop a framework that allows the model to include molecular biological data. In the second phase I want to apply the model to data collected within the CAMPOS project.