Karst aquifer impact on the formation of surface runoff: case study of the Resava River catchment, Serbia

The paper compares the flow regimes of the Resava River at the gauging stations of the Manasija Monastery (upper course) and the town of Svilajnac (lower course). The hydrological analysis encompasses a multiyear period of monitoring (1982–2020). The water budget and baseflow index are assessed for the catchment areas monitored by the Svilajnac station (683 km2) and the Manasija Monastery station (358k m2), considering the overall monitoring period and characteristic years. The results indicate that the specific runoff in the upper catchment is about 50% higher than that of the entire catchment. The reason is that the upper catchment is 55% karst, whereas the remainder is non-karst. The situation is similar in dry years. However, in wet years the specific runoff of the entire catchment is higher than that of the upper catchment.