Using the ICONA Model to Assess the Current Erosion Risk Status in Artvin's Hopa Stream Catchment and Connecting It to the Catchment's General Morphological Features

The study aimed to elucidate the cause-and-effect relationship between morphological structure and soil erosion risk, while mapping the physical characteristics and areas susceptible to erosion for the Hopa Stream Catchment (HSC) in Artvin province. For this purpose, in this study, the morphological characteristics of HSC were determined through Geographic Information Systems (GIS), and the current erosion risk status of the catchment were assessed using the ICONA model. A Digital Elevation Model (DEM) wasacquired from the Earth Explorer platform of the United States Geological Survey (USGS) for the morphological analysis of the catchment. This model facilitated the analysis of fundamental morphological attributes, including catchment boundaries, water flow direction and accumulation, aspect, slope classes, and drainage network within a GIS environment, resulting in the production of relevant thematic maps. In the erosion risk analysis, parameters including slope, geological structure, soil protection status, land cover, and land use were incorporated into the ICONA model. Land cover data were sourced from stand maps provided by the Artvin Regional Directorate of Forestry, while land use data were derived from CORINE 2018. A potential soil erosion risk map for the catchment was generated by overlaying these layers. The analysis indicated that the catchment has an altitude ranging from sea level to approximately 1858 meters and a dominant north-facing aspect (35%). Areas with slopes exceeding 20% comprise 87.5% of the catchment, and the primary drainage branch, Hopa Stream, flows in an east-west direction. The erosion risk map generated by the ICONA model indicates that the catchment primarily falls within the "medium" (81.20%) and "high" (13.69%) erosion risk categories. The erosion risk map, when overlaid with land use data, indicates that areas with high erosion potential predominantly occur on steep slopes and at high altitudes, coinciding with areas where forest cover has been replaced by tea cultivation.