|Metals and other pollutants in soils, sediments, groundwater and urban dust, atmospheric deposition, remediation technologies.
This field includes several aspects of applied geochemistry on the behavior of metals in soils, sediments and groundwater. The main emphasis of these studies is on the chemical speciation of mercury in environmental media. Within these projects different methods for determining mercury species and mercury binding forms in solids and aqueous solutions developed and compared. In the frame of several projects.
These studies include investigations on the spatial and temporal evolution of Hg dispersion in the atmosphere-soil-groundwater system and risk assessments of Hg contaminated soil and groundwater based on Hg speciation. We also applied the concept of risks assessment based on metal-speciation to test and monitore passive in-situ remediation technologies such as in situ immobilization of mercury. The goal is to use naturally occurring transformation processes of metals and other pollutants as a remediation strategy to achieve immobilization, passivation or degradation of the pollutant. This concept was realized in a first step in laboratory studies on testing filtering materials for highly effective mercury retention in funnel-and-gate groundwater clean up systems.
Another emphasis of my research is the investigation of environmental problems caused by mining activities (mercury and gold). This topic has become increasingly important during the last years due to closing of most mercury mines after a mining history of hundreds or thousands of years leaving behind a legacy of enormous environmental problems. My current and future work in this field, will include the characteriziation of Hg species in mine residues, dust, soils and lacustrine and marine sediments, and the dispersion of different Hg species in the soil-freshwater-marine system dependent on hydrological conditions and transport mechanisms. These interdisciplinary studies are carried out in cooperation with international partners from Slovenia, Italy, Spain, and the United States.
Trace element deposition, natural sources, natural variablity, trace element dispersion related to weathering processes, climatic variability, archives, peat bogs, sediments, biogeochemical transformation of organic matter in bogs, limnology, paleo-climate
My second field of research is related to basic research on the natural dispersion and evolution of trace elements in remote pristine environments such as sub-Antarctic regions. This includes the spatial and temporal variation of trace element deposition recorded in geochemical archives such as peat bogs and lake sediments, dependent on climatic conditions, weathering processes and/or geochemical redox-controlled processes within these natural archives.
My current studies focus on the evolution and history of the deposition of Hg and other trace elements in peat bogs and lakes in the Magellanic Moorlands, Chile 53 °S. Besides the influence of anthropogenic emissions I am interested in climatic processes controlling the atmospheric deposition of Hg and other trace elements in pristine areas e.g. how does the atmospheric trace element deposition vary during cold and warm periods. This includes studies on the speciation of atmospheric Hg and the investigation of halogene fluxes to the peat bogs in our study area. The major aim of these studies is the development of dispersion models which could help understand the global transport of trace elements emitted from anthropogenic, or natural sources and the contribution of the different emission sources to global fluxes.