GIS-based analytic hierarchy process (AHP) for soil erosion-prone areas mapping in the Bone Watershed, Gorontalo, Indonesia

The main problem faced by the developing countries globally in land management is soil erosion. This study maps an area of soil erosion prone in the Bone Watershed, Province Gorontalo, Indonesia, using topographical attributes sourced from a Digital Elevation Model with a spatial resolution of 30 m. The geographic information system methods are integrated with the analytic hierarchy process. This study considered ten topographic factors: elevation, slope, profile curvature, plan curvature, aspect, flow length to the nearest stream, stream power index, topographic wetness index, terrain ruggedness index, and sediment transport index. The model's performance is assessed using the area under curve-receiver operating characteristic (AUC ROC) approach. According to the findings, slope and sediment transport index, as well as flow length to the nearest stream, had the most significant impact on soil erosion prone, with values of 0.202, 0.190, and 0.126, respectively. The overlaying maps of all topographic factors were divided into five zones: very low, low, moderate, high, and very high. High and very high zones were discovered in 22.7% and 0.3% of the entire research area, indicating that the area is at a severe rate of soil erosion. The AUC ROC value for validating mapping results with datasets is 75.4%, showing that the AHP-GIS model's prediction is fair classification in mapping soil erosion-prone zones in the Bone Watershed. This research identifies significant soil erosion-prone zones in the hopes of assisting stakeholders and planners in developing a plan to reduce land degradation.