Analysis of plant root properties, texture and porosity that affects landslides in Tangka Sub-Watershed

Abstract

Tangka Sub-Watershed in West Sinjai District is one of the sub-watersheds in South Sulawesi, which often experiences landslides. Factors causing landslides were divided into control factors and trigger factors. One of the triggering factors for landslides is the characteristics of soil and plant properties. Several previous research results stated that soil characteristics greatly affect the occurrence of landslides, while plant roots help stabilize soil bonds and slopes. This study aims to determine the triggering factors of the soil (soil texture and porosity) and the distribution of plant roots that affect the occurrence of landslides. Soil texture analysis using hydrometer method. Soil porosity and moisture content using gravimetric and pycnometer methods. The results showed that the soil texture was dominated by silty clay loam impact on low soil cohesion. Intensive land use decreases soil porosity to <50% and increases soil bulk density to 1.4 g/cm3. The soil quickly becomes saturated and could induce the rotting of plant roots. These characteristics increase the vulnerability of the soil, thereby increasing the potential for landslides.