Assessment of soil erosion intensity using the erosion potential method: A case study of the Grdelica Gorge, Serbia

The South Morava River Basin was considered one of the most erosion-prone and flash flood-affected areas in the Republic of Serbia. This paper aims to apply the Erosion Potential Method (EPM) within a GIS environment to determine the spatial and temporal changes in the soil erosion coefficient, sediment production and transport, and to identify the factors contributing most significantly to erosion risk in the Grdelica Gorge for two reference years: 1970 and 2025. The intensity of soil erosion was analysed using the Erosion Potential Method according to Gavrilović. The results indicate that most of the area (62.03%) fell into slope category IV (27-70%), with all erosion categories represented. Processes of very slight erosion were predominant, covering 71.31% of the surface area (306.94 km²). The total annual sediment production (W year) amounted to 110,233.97 m3 year-1, while the specific sediment production (W sp) was 256.1 m3 km-2 year-1. The mean annual sediment transport was 81,573.14 m³/year, and the specific annual sediment transport was 189.51 m³/km²/year. A decline in population and the abandonment of arable land at higher elevations and steeper slopes, along with the implementation of extensive technical, biological, and biotechnical erosion control measures, contributed to erosion mitigation and enhanced vegetation recovery. Compared to the erosion intensity in 1970, the extent of severe erosion had notably decreased by 2025, while the proportions of slight and moderate erosion significantly increased. The mean erosion coefficient (Z mean) had decreased from 0.50 to 0.23.