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Highly mineralized springs in the Scuol-Tarasp area of the Lower Engadin and in the Albula Valley near Alvaneu, Switzerland, display distinct differences with respect to the source and fate of their dissolved sulphur species. High sulphate concentrations and positive sulphur (delta S-34) and oxygen (delta O-18) isotopic compositions argue for the subsurface dissolution of Mesozoic evaporitic sulphate. In contrast, low sulphate concentrations and less positive or even negative delta S-34 and delta O-18 values indicate a substantial contribution of sulphate sulphur from the oxidation of sulphides in the crystalline basement rocks or the Jurassic sedimentary cover rocks. Furthermore, multiple sulphur (delta S-34, Delta S-33) isotopes support the identification of microbial sulphate reduction and sulphide oxidation in the subsurface, the latter is also evident through the presence of thick aggregates of sulphide-oxidizing Thiothrix bacteria.

Intense snow sampling was carried out during 2003 and 2004 in two meso-scale catchments (Dreisam catchment, 257 km2, and Bergsee catchment, 11 km2) located in the southern Black Forest Mountains in Germany. The objective of the study was to describe the spatial variability of snow cover, snow water equivalent and isotope concentrations of deuterium (2H) and oxygen-18 (18O) in ‰ vs. VSMOW. Snow samples were collected with integral augers and characterized by geographical location, altitude, snow depths and snow characteristics. The results indicate a clear correlation of snow depth and water equivalent with altitude and a rather weak correlation of isotope concentrations to altitude. The isotope concentrations of 65 snow samples collected in 2003 varied between -10.2‰ and -14.9‰ for