Analysis of Riverbank Stability Due to Bamboo Vegetation in Walanae River, South Sulawesi, Indonesia

Bamboo vegetation is an endemic plant in Indonesia that grows on riverbanks. These plants have the potential to increase shear resistance due to the bond between the roots to the soil. However, an increase in plant weight due to its growth causes additional loads of soil. The condition triggers the release of soil on the slopes and causes riverbank sliding. Therefore, in developing the riparian ecological function, it is necessary to maintain the plants without neglecting the risk of physical damage to the river. This study aimed to estimate the risk of riverbank sliding due to the presence of bamboo plants by utilizing the bamboo vegetation conditions on the Walanae River. It was carried out on the 42.4 km riverbank in the middle area of Walanae watershed. The researchers selected 46 clumps of parring bamboo (Gigantochloa atter) as an endemic bamboo in this area and growing in the riverbank. The diameter of the bamboo trunk is the basis for an estimate of the weight of the bamboo clump. Furthermore, a numerical analysis was carried out by taking into account the load and shear resistance on the slope, including the weight of the plant. The research results indicated that bamboo is feasible to be applied for riverbank protection using the soil bioengineering method. The bamboo weight, which is indicated by the number of poles and diameter, significantly affects the stability of the slope. Therefore, the prevention of rising weight by harvesting method is critical to consider in riverbank protection