## 3 Results
### Extraction of Land Use Information on Collapsed Areas
#### 3.2.2 Results of Land Use Information Extraction in Subsidence Area  
The SSRN deep learning model is utilized to classify the land use information in the study area from 2017 to 2021. By doing so, we can obtain the land use information specifically within the collapse area of the study area, as shown in Figure 8. Based on this, we proceed to count the land use information within the collapse area of both the Zhaogu No.1 Mine and Zhaogu No.2 Mine separately. Figure 9 illustrates that between 2017 and 2021, the subsidence area covered a total of 1880.99 \(\mathrm{hm}^{2}\). The primary land use types in this region were cultivated land, built-up land, and water area. Between 2017 and 2020, the cultivated land area in the subsidence \begin{table}
\begin{tabular}{c c c c c} \hline  & **MLC** & **SF** & **SVM** & **SSRN** \\ \hline OA (\%) & 80.46 & 83.19 & 88.64 & 95.87 \\ AA (\%) & 80.05 & 83.31 & 88.45 & 95.92 \\ Kappa (\%) & 80.39 & 83.94 & 88.50 & 95.85 \\ \hline \end{tabular}
\end{table} 
Table 5: Comparison of classification accuracy of different methods. Figure 8: Land use types in subsidence areas, 2017–2021. area exhibited a consistent pattern, with the cultivated land covering over 70% of the total subsidence area. The yearly fluctuations in built-up land, forest land, water area, and idle land in the subsidence area were minimal, indicating a consistent pattern of stability. During the period of 2020-2021, there were substantial changes in the land use patterns in subsidence areas. These changes are primarily characterized by a major decrease in the area of cultivated land and a notable increase in the areas of water and idle land. The percentage of cultivated land area declined from 79.18% to 42.95%, while the percentage of water area rose from 10.23% to 41.65%. Additionally, the percentage of idle land area climbed from 1.01% to 8.1%. The substantial expansion of the water surface in the subsidence region in 2021 can be primarily attributed to the intense precipitation event that occurred locally between 17 July and 23 July 2021. This event resulted in a rise in groundwater levels, the creation of waterlogged areas, and the conversion of various land types, predominantly arable land, into water bodies. Furthermore, as a consequence of the abundant precipitation in the region, the rainwater effectively removed the surface vegetation in the mining zone, leading to a significant expansion of the idle land area. Figure 10 shows that the collapse area of Zhaogu No. 1 Mine is 1294.04 \(\mathrm{hm}^{2}\), whereas the collapse area of Zhaogu No. 2 Mine is 586.95 \(\mathrm{hm}^{2}\). The subsidence areas of Zhaogu No. 1 Mine and Zhaogu No. 2 Mine were relatively unchanged from 2017 to 2020, indicating a consistent and stable pattern. The cultivated land area in the Zhaogu No. 1 Mine subsidence region constitutes over 80% of the total area, while the water area makes up between 1% and 3%. In the Zhaogu No. 2 Mine subsidence area, the cultivated land area accounts for almost 50%, while the water area comprises more than 25%. Due to the presence of both permanent and seasonal waterlogging areas in the mining site, Zhaogu No. 2 Mine experiences more severe waterlogging compared to Zhaogu No. 1 Mine, primarily because of its lower elevation. Consequently, Zhaogu No. 2 Mine is prone to the formation of permanent waterlogged areas, which occupy a larger proportion of the site. During the period of 17 July to 23 July 2021, the subsidence areas of Zhaogu No. 1 Mine and Zhaogu No. 2 Mine experienced significant changes in land use types. These changes are similar to those observed in the subsidence areas of Zhaogu Mine. The main changes include a substantial decrease in cultivated land area and a substantial increase in water and idle land area. Among the two mines, Zhaogu No. 2 Mine has a higher rate of increase in water area (34.89%) compared to Zhaogu No. 1 Mine (28.77%). Additionally, the unused land area is also showing a trend of increase. The rate of idle land expansion in Zhaogu No.