A New Model of Landslide Prone Map Using a Combination of Scoring and Polygon Thiessen Methods

Landslide is an activity from balance disruption which triggers the movement of a mass of soil and rock down a sloped section of land. Boyolali Regency is one of 35 regencies in Central Java Province which has high vulnerability to landslide. In order to reduce the number of casualties and property loss, this study aims to create a new model of landslide prone area map using the parameters which cause landslide, such as rainfall, soil types, drainage, slope, and land cover. The parameters are processed and analyzed using the combination of the scoring method and the polygon thiessen method. The scoring method is implemented to determine landslide prone areas, while the polygon thiessen method is applied to do the overlay and spatial mapping of landslide prone areas. The hypothesis proposed in this study is that the combination of scoring method and the polygon thiessen can map landslide prone areas in Boyolali Regency accurately. The result of the study shows that the model of the landslide prone area’s accuracy is 83.3%. The landslide prone area map shows the four sub districts in Boyolali Regency which meet the criteria of high landslide vulnerability level are Solo, Ampel, Musuk and Cepogo Sub Districts.