An Integration of the Fractal Method and the Statistical Index Method for Mapping Landslide Susceptibility

Abstract

AbstractAppropriate land use planning and the sustainable development of residential communities play a crucial role in the development of mountainous provinces in Vietnam. Because these regions are especially prone to natural disasters, including landslides, landslide studies can provide valuable data for determining the evolution of the landslide process and assessing landslide risk. This study was conducted to assess landslide susceptibility in Muong Khoa commune, Son La province, Vietnam, using the Statistical Index method (SI) and the integration of the Fractal method and Statistical Index method (FSI). To produce landslide susceptibility zonation (LSZ) maps, eight causative factors, including elevation, slope aspect, slope, distance to roads, distance to drainage, distance to faults, distance to geological boundaries, and land use, were considered. Using SI and FSI models, two landslide susceptibility zonation maps (LSZ) were produced in ArcGIS, and the study territory was categorized into five susceptibility zones: very low, low, moderate, high, and very high. The area percentage of susceptibility zones predicted by the SI model is 10.11, 18.49, 29.71, 28.59, and 13.10%, respectively. Meanwhile, the susceptibility map generated by the FSI model divided the study area into zones with corresponding area proportions of 18.92, 18.71, 20.01, 22.94, and 19.42%. Using the ROC method, the prediction performance of the two models was determined to be AUC = 71.18% (SI model) and AUC = 75.18% (FSI model). The AUC > 70% indicated that the models established a good relationship between the spatial distribution of past landslides and causative factors. In addition, the two models accurately predicted the occurrence of landslides in the study area. The FSI model has improved prediction performance by identifying the role of each factor in the landslide occurrences in the study area and, therefore, may be effectively utilized in other regions and contribute to Vietnam’s landslide prevention strategy.