engleski

The influence of the Plitvice watercourse on the karst aquifer: The case study from the National Park Plitvice Lakes, Croatia

During 2021, hydrogeological research was conducted in the Plitvice Lakes National Park (PLNP). The aim was a detailed investigation of the Plitvica subcatchment area that in a broader sense represents about a quarter of the Plitvice Lakes catchment, the principal catchment area in the PLNP. The Plitvice subcatchment includes all waters that gravitate to the Plitvice watercourse. The important of this subcatchment is in fact that the part of water outflow from this area via Plitvica watercourse that ends at the Big Waterfall (Veliki slap), the most important touristic spot in the PLNP. Other part of water sinks in several ponor (swallow-hole) zones along the Plitvice watercourse and flows underground. This is a problem that has been observed ever since hydrological research in this area began in the late 1970s, particularly during summer dry periods when Big Waterfall almost runs out of water. This study was focused on groundwater. Simultaneous tracing of groundwater flows with different tracers from several swallow-hole zones along the Plitvice watercourse has been performed, more precisely hydrogeological influence of the catchment area on the hydrogeological downstream areas has been defined and natural vulnerability, hazards and risks maps have been made Research and analyses have also confirmed that the Plitvica watercourse has an impact on the naturally very vulnerable karst aquifer, and that the vulnerability of the aquifer can significantly affect the Klokot spring in the neighbouring Bosnia and Herzegovina. Namely, the tracer test showed a strong hydraulic connection between these two areas. Moreover, it can be concluded with certainty that the majority area of the Plitvice watercourse that flows through well-permeable carbonate rocks of Upper Cretaceous age, represents the swallow-hole zones of the Klokot spring. Regarding the reduction of water losses along the Plitvice watercourse, it was determined that the losses were caused by anthropogenic influence (water intakes for water supply purposes), but also by natural conditions (breaks in the watercourse banks and greater spillage of water into swallow-holes zones). Due to that, measures to mitigate the negative impacts of water losses from the Plitvice watercourse, with special emphasis on possible anthropogenic impact, have been proposed.

Plitvice Lakes National Park ; Groundwater tracing test ; Water losses ; Plitvica watercourse ; Croatia

nije evidentirano