A comparative study of stream sediments in central Norway collected a quarter of a century apart: assessing anthropogenic impact

Stream sediments do not only provide an integrated signal of geochemical processes and erosional regimes occurring in drainage basins (Galy and France-Lanord, 2001; Vance et al., 2003) but they also provide a tracer for human influences (Walling, 1999). A comparative study of stream sediments from both populated and non-populated areas in the Trondheimfjord region collected 25 years apart will provide a unique opportunity to study the effect of recent climate and anthropogenic changes in this region. In this project, the partners intend to study a new set of samples collected from some of the previously sampled sites in order to investigate whether climate change and anthropogenic activity have left a quantifiable imprint in the last 25-30 years. The dat a collected will provide municipalities and decision makers with valuable information to determine how the geochemistry of the ecosystem might be influenced by future anthropogenic activities and climate change and thus improve the knowledge base required for regionally reducing future undesired impacts on the environment. The planned investigations will help to understand if recent climate changes and expanded anthropogenic activity in the coastal areas of the Trondheimfjord have affected the natural hyd rological and ecological cycles in the adjacent drainage basins. The project includes geochemical, mineralogical and sedimentological investigations using state-of-the-art instrumentation and methodology. Data will be acquired in the field and laboratory and jointly processed at the Norwegian Geological Survey (NGU) in Trondheim and ETH, Zurich.