Geochemical Map of Croatia – Key findings and legacy of geochemical mapping in the Pannonian Basin

The Geochemical Atlas of Croatia revealed differences in the spatial distribution of geochemical elements between the Croatian Dinaric coastal region and the Pannonian Basin. In the Pannonian Basin, 1,254 topsoil samples (0–25 cm) were analysed for 27 elements and pH values. This geodynamic unit is characterised by the variability of geological, pedological and land-use-related characteristics. To analyse the geochemical properties of soil above different lithological units, soil types and land use and land cover classes, a discriminant function analysis was performed using the compositional data. The study shows significant geochemical and ecological patterns, with the first two discriminant functions explaining a major proportion of the variability: in the GEOLOGY model, DF1 explains 33.31% and DF2 17.97%; in the SOIL model, DF1 explains 51.59% and DF2 20.22%; in the CLC model DF1 explains 59.85% and DF2 30.30%. The geological model distinguishes between the Quaternary sediments and the older lithological units and highlights alkaline and acidic soil conditions. The soil model shows the effects of fluvial and alluvial deposits, agricultural practices and the underlying geology on soil composition and emphasises the enrichment of essential nutrients and heavy metals in the soils. The land use and land cover model illustrates the anthropogenic influence on agricultural soils and the susceptibility of wetlands to heavy metal accumulation. The results obtained illustrate the complex interaction between geology, the topsoil layer, as well as land use and land cover, providing awareness for environmental management and monitoring, and the need for further geochemical studies of the soils in the Pannonian Basin.