The European Geosciences Union General Assembly, one of the leading international forums in the geosciences, was held again in 2026. The József and Erzsébet Tóth Endowed Hydrogeology Chair was represented at the event through several research contributions.
Dr Anita Erőss contributed to the scientific programme of the conference as co-chair of the session NH8.1 Radioactivity in the environment: scientific challenges and technological innovations. The session focused on scientific challenges, technological innovations and tracer methods related to radioactivity in the environment.
Anita Erőss’s presentation, entitled “A multi-tracer approach reveals groundwater inflows to a soda lake and its streams suffering from water shortage in Hungary”, presented research on groundwater recharge to Lake Velence and its connected streams in the “Tracing Water and Sediment Pathways Across Time and Space: Integrating Hydrochemical, Isotopic, Modelling, and eDNA Approaches” session. By applying stable and naturally occurring radioactive isotopes, including uranium and radon, the study demonstrated that the role of groundwater in the lake’s water budget cannot be overlooked. The results provided physical evidence of groundwater inflow into Lake Velence and its inflowing streams, while also offering a detailed picture of the spatial distribution of these inputs.
Dr. Szilvia Simon also participated as a co-chair in organizing the session entitled “Approaches for Enhancing Sustainable Water Management and Solving Environmental Issues.” The aim of the session was to present case studies and scientific results that support the sustainable use and protection of groundwater, with particular emphasis on addressing pollution, overexploitation, and other environmental challenges.
She also took part in the scientific programme together with her undergraduate student, Aldeth Garas. Their study, titled “The Effectiveness of Water Retention in Canals in the Danube–Tisza Interfluve Region, Hungary”, examined the effectiveness of canal-based water retention in the Bátya area of the Danube-Tisza Interfluve. The research analysed the response of the shallow groundwater system using water level monitoring, hydrochemical analyses, soil and sediment investigations, electrical resistivity tomography, and numerical simulation.
The results presented on the poster showed that the regulation of canal water levels created a detectable hydraulic connection between the canal and the surrounding groundwater system. The observations indicated a delayed groundwater response, a decreasing effect with increasing distance from the canal, and ionic dilution in the nearest monitoring well, suggesting mixing between canal water and groundwater. Based on numerical simulations, water retention may lead to higher saturation levels and improved local water storage when regional groundwater flow is also taken into account; however, the effectiveness of the method is strongly site-specific.
The common message of the presented studies is that a more accurate understanding of the role of groundwater is essential for water management in landscapes affected by water shortage, drought and climate change. The results presented by the Chair at EGU26 contribute both to the scientific understanding of surface water–groundwater interactions and to the development of nature-based and water-retention-based solutions.