HYDROGRAPH SEPARATIONS BASED ON ISOTOPICCHEMICAL MIXING MODELS

摘要

Hydrograph separation of rainfall-runoff events in the Wudaogou Hydrological Experimental Catchment (WHEC) in north Anhui Province of China was carried out using stable isotopes oxygen-18 and deuterium, electrical conductivity (EC) and specific concentration of calcium as hydrological tracers. The streamflow components were determined in the study area with particular focus on the spatial and temporal variations of catchment sources. Precipitation, soil water,groundwater and streamwaters were sampled and analyzed for Calcium, EC, 18O and 2H, which were finally selected to assess the different contributing sources using mass balance equations and end-member mixing diagrams. This analysis indicates that despite the uncertainty, the flow sources,which generate the stream flow, are clearly identified at the WHEC scale by the application of the isotopic-chemical mixing model.