The risk of landslides in The Jlantah upstream watershed in Karanganyar Regency in 2022

Abstract

The Jlantah watershed (DAS) is a tributary of the Bengawan Solo River with an area of ±2,247 hectares, located on the western slope of Mount Lawu, including Tawangmangu District and Jatiyoso District, Karanganyar Regency. Regional developments in the eastern part of Karanganyar Regency, supported by improved accessibility of the road linking Karanganyar Regency with Magetan Regency, will create new growth centres to diversify use. The development of agribusiness-oriented dryland agriculture, natural tourism destinations, and the establishment of residential buildings provide more employment and business opportunities to improve the government’s and surrounding communities’ economic conditions. In other parts of the land characteristics in the Jlantah watershed, there are 68.78% very steep land slopes (>40%), 62.74% of the type of soil is greyish brown andosol and lytosol complex, and the rock structure has minor faults. The study aimed to determine the vulnerability, vulnerability, and risk of landslides in areas with other regional developments. This research was conducted in the Jlantah Upstream watershed, which includes: Tawangmangu Subdistrict (Blumbang Village, Gondosuli Village) with high environmental pressure and Jatiyoso District (Beruk Village) with low ecological pressure. The research method is quantitative descriptive with the determination of hazard, vulnerability, and risk of landslides using scoring and weighting from documentation data and observation results. The results of the study are: Blumbang Village, Gondosuli Village, and Beruk Village have a high category of hazard and vulnerability to landslides, while the risk of landslides has a medium class.