Spatial distribution analysis of Hungarian oak in Serbia based on second national forest inventory data

The aim of this research is to use advanced technologies and selected statistical methods to more accurately assess and quantify the spatial distribution of Quercus frainetto (Hungarian oak) in Serbia. The study is based on data from the Second National Forest Inventory of Serbia (NFI-2), conducted between 2019 and 2022. The presence of Hungarian oak was recorded on 1,032 sample plots. For each of these plots, data were extracted from the NFI-2 database, including soil type classified according to WRB, elevation, slope, aspect, and the forest region to which each plot belongs. The data were analyzed using a combination of statistical and spatial methods supported by GIS tools (Kernel Density analysis and Hot Spot/ Getis-Ord Gi* analysis). The results indicate that Hungarian oak most frequently occurs at elevations between 250 and 600 m, on moderately to steeply inclined slopes (10?-25?), and predominantly on south and southwest aspects, confirming its thermophilous character. The highest occurrence was observed on Cambisols, whereas at higher elevations and steeper terrains the species also appears on Leptosols, demonstrating its ability to persist under more restrictive ecological conditions. Kernel Density analysis clearly identified two zones of high concentration of this species: southeastern Serbia, representing the core of its range, and western/ southwestern Serbia as another significant area of increased density. The Hot Spot analysis confirmed statistically significant ?hot spots? in these regions, while ?cold spots? were located in the lowland parts of central and northern Serbia. The applied approach, which integrates NFI data with GIS analyses, enables a clearer and more quantified understanding of the spatial distribution of Hungarian oak, as well as other tree species, providing a more reliable basis for forest management and forest monitoring.