# Application of Compound Terrain Factor LSW in Vegetation Cover Evaluation
## 5 Summary  
Given that the majority of the existing vegetation indices use optical images as data sources, the two-dimensional indicators obtained are challenging to express the spatial heterogeneity of complex three-dimensional structures [102]. This problem is more pronounced in mountainous cities [103], and the use of topographic factor for the expression can somewhat ameliorate this shortcoming. In this study, the integrated slope factor LSW was found to be highly regular in revealing vegetation growth potential. Through the introduction of the Certainty Factor, the application of LSW for vegetation coverage assessment was proved to be reliable after a control group test. At the same time, the mechanism of LSW acting on vegetation growth proved to be correct. In addition, LSW can effectively delineate the vegetation susceptibility zoning maps of the 10 counties (cities) in Sichuan Province, and the vegetation coverage in the high and very high susceptibility zones accounts for more than 80%, confirming \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline
**Susceptibility** & **LSW Value** & **Graded** & **Vegetation Cover** & **Vegetation** & & & \\
**Level** & **Range** & **Area/km2** & **Area/km2** & **Coverage/\%** & **A/\%** & **B\%** & **B/A** \\ \hline I & 0–0.08955 & 2279.97 & 393.95 & 17.27 & 8.71 & 2.03 & 0.2331 \\ II & 0.08955–0.18931 & 5044.07 & 3352.20 & 66.45 & 19.27 & 17.28 & 0.8967 \\ III & 0.18931–0.26861 & 8210.95 & 6519.02 & 79.39 & 31.37 & 33.60 & 1.0711 \\ IV & 0.26861–0.35558 & 6942.36 & 5808.06 & 83.66 & 26.52 & 29.93 & 1.1286 \\ V & 0.35558–0.65487 & 3700.43 & 3328.77 & 89.95 & 14.13 & 17.16 & 1.2144 \\ Total & & 26,177.81 & 19,402.02 & & 100 & 100 & \\ \hline \hline \end{tabular} Note: (1) A is the percentage of the area designated with a certain susceptibility class to the total area of the study area; (2) B is the percentage of vegetation within the designated susceptibility class to the total vegetation.  
\end{table} 
Table 3: Comparison of susceptibility level zoning and actual vegetation distribution data. that the results of the assessment are true and credible. In particular, the values range of LSW greater than 0.26 can be used as a reference for delineating regional areas of vigorous vegetation growth. In the process of exploring the association between LSW and vegetation coverage, the indicative relationship between LSW and soil erosion was additionally revealed. For the range of 10 counties (cities) in Sichuan Province, there is a highly significant negative correlation between LSW and K. When LSW lies in the interval of 0 to 0.2, there is a significant decrease in the value of K. With LSW locates at the level of 0.2 to 0.3 values, the K value will remain stable. As the LSW value is greater than 0.3, the K value will show a gradual downward trend. In summary, the correlation between slope development, erosion, and vegetation growth can provide corresponding decision-making knowledge in the fields of erosion control and ecological restoration. With the increasing public availability of DEM, scholars can easily access DEMs in different time domains and carry out numerical dynamic supervision of LSW in the study area. In the event that a staged change in LSW is detected, early warning or contingency measures can be provided in a timely manner. For example, when a sharp decrease in LSW values is monitored in a localized area, it reflects the drastic fluctuation of soil erosion in this range, and the frequency of soil physicochemical property supervision should be increased at this time in order to prevent gully wall collapses or landslide disasters from occurring [23]. For the field of ecological management, LSW numerical monitoring can provide recommendations for ecological restoration. For instance, when delineating the area of planted forests, priority can be given to areas with large LSW values.