5. Hydrogeochemistry of surface water in Slovakia

The paper provides information on characteristics and genesis of surface water in Slovakia. The focus is in the chemical and isotopic analyses of samples of surface water. The input data are represented by 10,960 samples within the geochemical mapping of Slovakia. The interpretation is based on a conceptual model of the formation of the chemical composition of the surface water in the conditions of the Western Carpathians. Based on its end members formation, the surface water is divided on the basis of five dominant types of lithogeochemical environs in watersheds. Individual earmarked end types are characterized on the basis of statistical methods and thermodynamic modelling. According to composition of oxygen and deuterium isotopes the molecule of water itself is clearly of meteoric origin. Approximately 6.5% of the main ions content is of the same origin. The rest of the chemical composition of a surface stream is caused by the interaction of water - rock - gas. Its source is the direct interaction in the bed, and wash-off and inflow of groundwater into a surface stream. The last factor of the chemical composition formation are anthropogenic impacts of different nature. (authors)