# Application of Compound Terrain Factor LSW in Vegetation Cover Evaluation
## 4 Results and Discussion
### Method Application  
The final acquisition of the overall LSW distribution of the study area is shown in Figure 8a. In the previous analysis, the higher the value of LSW factor, the higher the possibility of vegetation cover in the corresponding grid cell. The LSW distribution map in the study area was reclassified using the natural breaks classification commonly used in statistics, and finally divided into five grades, arranged from smallest to largest possibility corresponding to grade I to V. The higher the level, the higher the possibility of vegetation occurrence. The different levels of susceptibility correspond to very low, low, medium, high, and very high, in order, and the vegetation susceptibility zoning map is displayed in Figure 8b. In terms of intuitive distribution, the susceptibility level in the southeastern part of the study area is lower, and can be judged on the basis of LSW that the vegetation distribution here is less dense than in other regions. The study area can be roughly divided into northern, central and southern parts based on latitude range. In the northern and southern parts, the vegetation susceptibility class in the western region is clearly higher than that in the eastern part, while the central region shows an even distribution of vegetation between the eastern and western sides. After comparing the river data in the test area, it was discovered that the eastern part of the central region is a convergence area of water systems such as the Baicao River, Tongkou River, Anchang River, and Kai River. With fertile soil, the  
Figure 8: Distribution of LSW and vegetation susceptibility classes in the study area. (**a**) Distribution of LSW, (**b**) distribution of vegetation susceptibility classes. vicinity of the water system is often a deep-cut canyon zone [98]. Moreover, soil water content in the canyon zone has a significant positive correlation with soil microbial biomass carbon and nitrogen as well as soil enzyme activities [99], thus producing an effect on vegetation development. Overall, the susceptibility level in the west was higher than that in the east, so the comprehensive conditions in the west were judged to be more suitable for vegetation growth. The corresponding data were obtained by overlaying and analyzing the graded susceptibility classes with the actual vegetation cover distribution data, as shown in Table 3. With the combination of Table 3, it can be seen that the vegetation coverage differs significantly in different susceptibility classes, demonstrating a clear regularity with the increase of classes. The shift from 17.27% vegetation coverage in susceptibility grade I to more than 80% in grades IV and V also confirms the validity of the susceptibility class zoning map. In order to more directly assess the reliability of the rank zoning maps, this paper derives the actual vegetation occurrence rate B/A from the actual landslide ratio [71,100], which is commonly used in the field of landslide susceptibility assessment. The physical significance of this ratio is that it reflects the relationship between the frequency of vegetation occurrence and the conditions under which it is likely to occur [101]. A higher occurrence rate (B/A > 1) indicate that more vegetation events have happened than are likely to occur, suggesting that a high likelihood of occurrence exists, while the opposite is true for a relatively low likelihood of occurrence of vegetation on the surface. Based on Table 3, it can be seen that as the susceptibility level gradually increases, the ratio B/A increases simultaneously. The B/A value increased from the initial 0.23 to about 1.21, and the actual occurrence ratio of vegetation increased nearly six times, indicating that the obtained susceptibility class matches the actual vegetation occurrence and the classification result is more satisfactory. Statistically, the vegetation cover in grades IV and V accounts for 47% of the total vegetation cover area, making up almost half of it.