Environmental Geochemistry

We investigate biogeochemical processes and interactions at the micro level up to entire ecosystems. The main focus is on understanding processes of interactions of organic substances with trace elements and their coupling to hydrological and climatic factors.

We are interested in the effects of anthropogenic activities on biogeochemical cycles of trace elements and inorganic pollutants.

Our current research projects focus on the role of peat decomposition in the accumulation and release of metals from peat bogs and on mercury isotope ratios as a tool for determining species transformation processes in contaminated soil-aquifer systems.

Remediation of Mercury Contaminated Sites

We investigate mercury contaminated sites and develop methods to stabilize or remove mercury from polluted soils or groundwater. Our current emphasis is on the species-based development and application of filtering materials for removal of mercury from contaminated groundwater and on species transformation processes which reduce mercury mobility in soils and groundwater.

Geochemical Archives and Formation of Environmental Signals

We conduct several projects on the formation of environmental signals based on biogeochemical proxies. We are interested in understanding what geochemical signals indicate and how they are preserved in geo-archives such as peat bogs and lake sediments. We apply multi-element analytical methods including organic matter characterization and multivariate statistics.

Biogeochemical Cycles

We investigate coupling of trace element and organic matter cycling on a micro- to ecosystem scale. Main emphasis is the understanding of processes of trace element organic matter interactions and their coupling to hydrological and climatic drivers, which both control release of trace element and carbon from soils to aquatic systems. Currently, we study the release of dissolved organic matter associated lead and arsenic from wetlands to drinking water reservoirs.

Mercury Speciation and Risk Assessment

We have developed analytical methods which allow speciation of mercury phases and species in all kinds of solid matter such as soils, sediments, and mining residues. We apply these methods in combination with geochemical modeling to several mercury-contaminated sites worldwide for risk assessment and remediation strategies.