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| Conditioning factors | Description | Data sources | Grading standards | Class |
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| Topographic and geomorphic factors | Terrain information entropy | Terrain information entropy is based on the digital elevation model (DEM), combined with information entropy to quantitatively describe the roughness and undulation degree of the local surface, including comprehensive indicators of elevation, slope, and aspect. | Terrain information entropy is calculated using 1:350,000 DEM data | The steeper the change of the index values such as elevation, the richer the terrain information, and the smaller the terrain information entropy. The model is trained using the original value of terrain information entropy. | — |
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| Geological environment factors | Distance to rivers | The river has erosion and impacts on the slope and bank, and the rise and fall of groundwater changes the effective stress in the rock and soil mass, thereby affecting the landslide. | The data of the distance to the river is extracted from the vector map, and then the data layer is generated in ArcGIS | Distance to rivers is artificially classified; the closer the distance to the water system, the higher the series, and the greater the probability of landslides. | Level 1: >10 km |
| Level 2: 5–10 km |
| Level 3: 2–5 km |
| Level 4: 1–2 km |
| Level 5: <1 km |
| Distance to faults | The mechanical properties and spatial distribution of faults affect the development scale and spatial distribution of landslides and are the basic factors controlling the formation of landslides. | The data of the distance to the fault is extracted from the vector map, and then the data layer is generated in ArcGIS | Distance to faults is artificially classified; the closer the distance to the fault zone, the higher the series, and the greater the probability of landslide occurrence. | Level 1: >15 km |
| Level 2: 8–15 km |
| Level 3: 5–8 km |
| Level 4: 2–5 km |
| Level 5: <2 km |
| Lithology | The lithology determines the stress distribution, strength and deformation, and failure characteristics of slope rock mass, and it is one of the crucial factors for landslides. | Lithology reflects the stratigraphic conditions of the study area, and it comes from a 1:500,000 regional geological map | The lithology is artificially graded according to the softness, hardness, and stability of the strata, and the lithology of the main strata at all levels is shown in the notes1. | Level 1: hard |
| Level 2: less hard |
| Level 3: soft |
| Level 4: weak |
| Level 5: loose rock |
| NDVI | NDVI is an important index to measure vegetation coverage, which reflects the growth of vegetation and prevents the occurrence of landslides to a certain extent. | NDVI is obtained from the remote sensing images in 2010 through atmospheric correction, cloud processing, and other links and then calculated by the maximum value of the annual data synthesis (data from Landsat7 ETM SLC-off 30 m resolution data set) | The larger the NDVI, the higher the vegetation coverage. The model is trained using raw NDVI. | — |
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| Inducing factors | Distance to roads | Indicates the destructive effect of human engineering activities on natural slopes. Road construction changes the stability of the mountain, making it prone to landslides. | The data of distance to roads is extracted from the vector map, and then the data layer is generated in ArcGIS | The distance to roads is artificially graded. The closer the distance to the road, the higher the level, and the greater the probability of landslides. | Level 1: <1 km |
| Level 2: 1–2 km |
| Level 3: 2–5 km |
| Level 4: 5–10 km |
| Level 5: >10 km |
| PGA | It represents the horizontal acceleration corresponding to the maximum value of the ground motion acceleration response spectrum during the earthquake vibration process, and the earthquake is a key factor causing landslides. | PGA from the USGS (https://www.usgs.gov/) | The PGA is artificially graded. The larger the PGA, the higher the series, and the greater the probability of landslides. | Level 1: <0.2 g |
| Level 2: 0.2–0.35 g |
| Level 3: 0.35–0.5 g |
| Level 4: 0.5–0.6 g |
| Level 5: >0.6 g |
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