Research

Wie steuert Eisen die Mobilität von Schad- und Nährstoffen in der Umwelt?

Iron is the fourth most abundant element in Earth’s crust and one of the most important redox-active elements in natural environments. Its ability to switch between Fe(II) and Fe(III) drives mineral transformations and strongly influences the mobility of nutrients and contaminants. Using spectroscopic (Fe EXAFS, Mössbauer) and microscopic (SEM, TEM) techniques, our group investigates Fe(II) oxidation, contaminant co-precipitation, and iron mineral transformations under both oxygen-rich and oxygen-free conditions.

This is particularly important for environments prone to flooding, where changing redox conditions can profoundly alter iron cycling and the fate of associated elements—and may become increasingly relevant under climate change.

How do sulfur redox processes control biogeochemical cycles in wetlands?

Sulfur cycling is a fascinating yet surprisingly understudied component of wetland biogeochemistry. In oxygen-limited environments such as peatlands and coastal wetlands, sulfate can be rapidly transformed into sulfide, which strongly interacts with iron minerals and can trigger cascading reactions that influence both iron and carbon cycling.

Our research explores sulfur redox transformations and their links to iron and carbon cycling in wetlands. Combining field studies, experiments, and advanced analytical techniques, we investigate sulfur dynamics and their role in wetland biogeochemistry.

How can phosphorus cycles be sustainably closed?

Phosphate is an essential nutrient, but its excessive input into surface waters contributes to eutrophication. At the same time, phosphate is a finite and increasingly valuable resource. Our research therefore focuses on developing approaches for a circular phosphate economy. We investigate innovative iron-based sorbents for efficient phosphate recovery, as well as methods to improve phosphate release from secondary resources such as incineration ash.