Landslide susceptibility zonation using weight of evidence method in Mertelu and Tegalrejo, Gedangsari, Gunungkidul, Special Region of Yogyakarta, Indonesia

Mertelu and Tegalrejo are situated in the Gedangsari Sub-district, Gunungkidul Regency, Special Region of Yogyakarta, Indonesia. Located in the northern Baturagung Range, Southern Mountains Zone of East Java, with much hilly topography and mountainous areas with steep slopes, Mertelu and Tegalrejo are prone to landslides. The purpose of this research is to produce a landslide susceptibility zone using the weight of evidence (WoE) method. There were 73 landslide data taken from December 2022 to January 2023. As much as 80 of the data were used as a training dataset for weighting and generating the model map, while the remaining 20 were used as a test dataset. Parameters used in this research include slope angle, lithology, distance to faults, distance to rivers, and land use. Each parameter was weighted using the WoE method, and then the map of each parameter was overlaid to produce a map of landslide susceptibility zones. The accuracy of the map was calculated using the area under curve (AUC) method, including the success rate curve (SRC) and prediction rate curve (PRC). Based on the research results, the landslide susceptibility zone in the research area can be categorized: (1) very low, covering 6.34 of the total research area, (2) low, covering 24.15 of the total research area, (3) moderate, covering 44.46 of the total research area, and (4) high, covering 25.05 of the total research area. The landslide susceptibility map shows that the research location is predominantly characterized by areas with medium to high susceptibility to landslides. The medium and high susceptibility zones are close to the rivers that serve as the alignment of the faults. The accuracy calculations result in an SRC value of 0.753 and a PRC value of 0.780, both can be classified as “good” performance. © 2024 The Author(s).