Vol17 No.2: 358-372
【Title】Analysing post-earthquake landslide susceptibility using multi-temporal landslide inventories — a case study in Miansi Town of China
【Author】LI Ning1; TANG Chuan1*; YANG Tao2; CHEN Ming1
【Addresses】1 State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China ; 2 Sichuan provincial Chuanjian Institute of Investigation and Design, Chengdu 610059, China
【Corresponding author】TANG Chuan
【Citation】Li N, Tang C, Yang T, et al. (2020)Analysing post-earthquake landslide susceptibility using multi-temporal landslide inventories — a case study in Miansi Town of China. Journal of Mountain Science 17(2). https://doi.org/10.1007/s11629-019-5681-7
【Abstract】The earthquake that occurred on May 12, 2008, in Wenchuan County aroused a great deal of research on co-seismic landslide susceptibility assessment, but there is still a lack of anevaluation method that considers the activity state of the landslide itself.Therefore, this paper establishes a new susceptibility evaluation model that superimposes the active landslide state based on previous susceptibility evaluation models. Based on a multi-phase landslide database, the probabilistic approach was used to evaluate landslide susceptibility in the Miansitownover many years. We chose the elevation, slope, aspect, and distance from the channel as trigger factors and then used the probability comprehensive discrimination method to calculate the probability of landslide occurrence. Then, the susceptibility results of each period were calculated by superposition with the activity rate. The results show that between 2008 and 2014, the proportion of areas with low landslide susceptibility in the study area was the largest, and the proportion of areas with the highest susceptibility was minimal. The landslide area with highest susceptibility gradually decreased from 2014 to 2017. However, in 2017, 15.06% of the area was still with high susceptibility, and relevant disaster prevention and reduction measures should be taken in these areas. The larger area under the receiver operating characteristic curve (AUC) indicates that the results of the landslide susceptibility assessment in this study are more objective and reliable than those of previous models. The difference in the AUC values over many years shows that the accuracy of the evaluation results of this model is not constant, and a greater number of landslides or higher landslide activity corresponds to a higher accuracy of the evaluation results.
【Keywords】Wenchuan earthquake; Activity rate of landslide; Probabilistic approach; Susceptibility assessment