Spatial Distribution of Landslide Potential and Soil Fertility: A Case Study in Baturiti District, Tabanan, Bali, Indonesia

Abstract

Baturiti District is an area with history of high landslides yearly. Steep topography and steep slopes are some causes of landslides in the area. Minimal information regarding the potential for landslides can result in many victims and large losses if the disaster occurs in Baturiti District, Tabanan Regency, Bali Province-Indonesia. This study is crucial because of the urgency of the two factors that trigger land degradation. There has been no research on landslides on agricultural land and their relationship with soil fertility. Identical soil fertility is in loose soil, while loose soil is relatively easy to experience soil movement and cause landslides. This simple statement needs to be scientifically proven implemented in this research. Such conditions become a novelty in this scientific article. The purpose of this study was to identify the potential for landslides, the impact on agricultural land, and its correlation to the fertility of agricultural land. The method used is a survey method, soil analysis in the laboratory, and scoring with several landslide parameters, namely land use, slope, rainfall, landform, and geological structure. Soil fertility status analysis refers to the Soil Research Center (PPT) 1995 with 5 important parameters determining soil fertility status: CEC, Base Saturation, C-Organic, P-Total, and K-Total. Spatial data parameters were analyzed using a Geographic Information System. The results showed that the highest landslide susceptibility area was horticultural agricultural land (2,369.11 ha), applied to steep to very steep slopes. Another cause is the landform factor of the volcano's upper slopes, which has a soil-forming fraction dominated by coarse materials and high rainfall. Baturiti sub-district has low, medium, and high soil fertility status. The correlation between the vulnerability to landslides and soil fertility by (R2= 0.526). Such conditions indicate that areas with high landslide susceptibility have low soil fertility status with moderate correlation.