Hydrological balance and runoff from a montane peat bog traced by water temperature

Peatlands are hydrologically significant landscape units in mountain headwater catchments in Central Europe. In this study, the contribution of a peat bog to runoff and its annual water balance were analysed and compared with those of a forested mineral soil hillslope. A mixing model method using the water temperature as a tracer was applied, and the resulting ratio of peat bog water in streams was incorporated into a hydrological model. The mean peat bog contribution during baseflow ranged from 33.4% during the cold season to 48.9% during the warm season, while during runoff events, the contribution reached over 83%. The simulated water balance results showed a higher actual evapotranspiration on the mineral hillslope, which suggests a higher total runoff from the peat bog (1523 versus 1327 mm/year on the mineral hillslope). The results of this study enable more reliable modelling assessments of peatland reactions to climate change.