Analysis of soil permeability and C-Organic in landslide events in Tangka Sub-Watershed

Abstract

One of the areas in South Sulawesi Province classified as prone to landslides is the Tangka Sub-watershed in the West Sinjai Sub-District. The factors used in making the susceptibility map in the West Sinjai area mostly use general characteristics, such as slope, slope shape, distance from the river, lithology, land cover, and rainfall. Several previous research results stated that internal soil factors significantly affect the occurrence of landslides. Therefore, this study aims to determine the internal characteristics of the soil, especially the permeability and C-organic soil, which affects the occurrence of landslides and create a susceptibility map based on the resulting frequency ratio value. Soil permeability analysis using permeameter method, C-Organic analysis using Walkley and Black method, and susceptibility maps using frequency ratio method. The results showed that the low permeability and c-organic level of the soil increased the soil susceptibility to landslide events and produced a more detailed map of the area susceptibility than using only general factors.