## 6 Conclusions  
In order to master the dynamic changes in the surface ecological environment of the subsidence area after mining in the Wangwa mine area, the study conducted long-term remote sensing interpretation of surface damage, a calculation of surface subsidence using DInSAR technology, and a scientific evaluation of the ecological geological environment. The main conclusions are as follows:  
(1) Using Sentinel-2 remote sensing imagery, the main types of surface damage in the Wangwa mining area from 2016 to 2022 were interpreted and obtained, including four categories: ground pressure damage, waste piles, water bodies, and subsidence pits. The scope of surface damage in each year of the Wangwa mining area was calculated. In 2022, the ground pressure damage area was 8.171 km\({}^{2}\), the waste pile area was 0.738 km\({}^{2}\), the water body area was 0.709 km\({}^{2}\), and the subsidence area was 9.155 km\({}^{2}\). The subsidence area of the Wangwa mining area increases within the year, and the ground pressure damage also shows a growth trend, but at a slower rate. The areas of water bodies and waste piles are relatively small, with a relatively flat overall normal trend.  
(2) DInSAR technology was used to obtain the ground subsidence range affected by mining in Yingtongyou mining area, Wangwa mining area, and Wangwa No. 2 mining area from 2017 to 2022. The mining-affected area in Yingtongyou was 2.80 km\({}^{2}\), in the Wangwa mining area it was 23.94 km\({}^{2}\), and in the Wangwa No. 2 mining area it was 8.74 km\({}^{2}\).  
(3) An EGER model based on distance function optimization was constructed. Slope, subsidence, ground occupation and damage, FVC, RSEI, precipitation, and temperature were selected as indicators for the EGER assessment frame. The weight calculation of the model uses a coupled method of AHP and EM, which reduces the influence of subjective weight model over-reliance on experience and improves the reliability of the model.  
(4) The EGER of the study area was categorized into three levels. The high-risk areas are primarily located within the Wangwa mining area, while the pre-investigation area and general investigation area maintain a good eco-geological environment quality. By 2022, the low-risk area increased by 47.05 km\({}^{2}\) compared to 2017, and the high-risk area had shrunk by 19.96 km\({}^{2}\). From 2017 to 2022, the areas with no significant change accounted for 80.5% and the areas with very significant decrease accounted for 11.1%, respectively, at 21.28 km\({}^{2}\) and 49.10 km\({}^{2}\).  
G.W.: writing--original draft, visualization, validation, methodology. L.Y.: writing review and editing, supervision, project administration, funding acquisition, formal analysis, conceptualization. P.L.: Writing and original language checking, data validation. X.W.: visualization, supervision. All authors have read and agreed to the published version of the manuscript.  
This research was funded by Natural Science Foundation of Ningxia (Grant No. 2021 AAC03426), the Open Fund of Key Laboratory of Mine Ecological Effects and Systematic Restoration, Ministry of Natural Resources (Grant No. MEER-2023-06), Open funds from the State Key Laboratory of Coal Mining and Clean Utilization (Grant No. 2021 CMCU-KF014), and Key Special Projects for the 2023 \"Science and Technology Revitalization of Inner Mongolia\" Action (Grant No. ZD20232304), and Ningxia Talent Support Project.  
Data Availability Statement: Data will be made available on request from the authors.  
The authors would like to acknowledge the open dataset of satellite images provided by the USGS and open survey data published by local Chinese governments.  
The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.  
**Figure A1.**_Cont._Figure A1: Cont.  
Figure A1: Thirty-period cumulative subsidence change map.