| Abstract:The spatial distribution of slope geohazards is closely related to the relief amplitude, but there was a lack of research on the optimal statistical unit, the types of geohazards, and the scale of geohazards. In view of this, taking Sichuan Province, a province with a huge span of geomorphologic units, as an example, the mean change-point analysis information method was applied to determine the optimal statistical unit, and the data statistical models, such as the frequency ratio model (FR), the information value model (SI), and the certainty factor method (CF), were used to study the impact of relief amplitude on the spatial distribution of slope geohazards. The result was showed that there was a significant positive correlation between the average relief amplitude and the size of the statistical window, with a window size of 20×20 being the optimal statistical unit, covering an area of 3.24×106 m2. Slope geological hazards were mainly distributed in hilly and low-relief mountain areas, with a total share of 68.9%. Among them, the susceptibility range for landslides was 50～350 m and for collapses susceptibility was 50～350 m. The areas with low relief amplitude were more favorable for developing small-scale geohazards, while regions with high relief amplitude were more favorable for developing medium to large-scale geohazards. |
