Search

Multi-media and multi-element geochemical survey carried over almost the whole of Europe indicate that baseline concentrations of chemical elements in samples of soil, humus, stream water and sediments (stream and floodplain) vary spatially by up to several orders of magnitude, because of geological, climatic and other factors, including inputs from different human actvities. The EuroGeoSurveys-FOREGS geochemical baseline project provides European decision-makers with data about the chemical comopsition of the near-surface environment at the end of the twentieth century. It is the „ baseline“ against which the next generation will quantify changes, whether natural or human-made. Although the sampling density used in the current project is low, approximately one sample site per five thousend square kolimetars (1 site/5000 km2), geochemists have been using quite effectively such low-sample density survey to cover large areas for the last forty years. This geochemical baseline survey provides us with invaluable information about the natural and human-induced concentrations of chemical elements in materials of the near-surface environment, where we live on, grow our crops, raise our livestock, and from which we extract our drinking water, and other raw materials, including mineral wealth. Our quality of life depends on the chemical composition of water (river or groundwater) and soil, whether residual (developed directly on bedrock) or alluvial (transported by river water and deposited during flood episodes on floodplains). The geochemical distribution maps show distinct geographical differences in the levels of potentially harmful elements from natural geogenic sources, includig lithology and mineralisation, and from natural processes such as climate, which influence the original levels. This geochemical variatin illustrates the difficulty in defining a single guidline value for „ water“ , „ soil“ and „ sediment“ to be applied all over Europe. Finally, the geochemical maps could be used to identify potential geohazard and geohealth risks for more detailed investigations.