## 3 A Comprehensive Monitoring System for Landslides in 'Space-Sky-Ground-Underground'
### Temperature distribution inside inclinometer tubes B1, B3, and B5
The elevation of the slope's top is 809 m, and the water level of the Three Gorges Reservoir at the front edge fluctuates between 145 m and 175 m, with a relative height difference of 634 m to 664 m. The slope aspect is 350\({}^{\circ}\), with an average slope inclination of 14\({}^{\circ}\), and the overall shape is a single-sided mountain with low north and high south. The slope structure is a steep south and a gentle north. The attitude of the exposed rock strata on the slope is 320-350\({}^{\circ}\)/16-33\({}^{\circ}\), and the dip angle of the rock strata gradually decreases from south to north. The slope structure is in a \"reclining\" shape. The main strata exposed on the slope are Quaternary landslide deposits (Q\({}_{4}\)del), the upper section of the Lower Jurassic Zhenzhuchong Formation (J\({}_{1}\)zh\({}^{2}\)), the lower section of the Lower Jurassic Zhenzhuchong Formation (J\({}_{1}\)zh\({}^{1}\)), and the Upper Triassic Xujiahe Formation (T\({}_{33}\)). [45; 46; 47]. Due to the periodic fluctuation in the water level and the abundant rainfall of the Three Gorges Reservoir area, the landslide is in a periodic sliding state. In addition, the surface layer of the slope is composed of landslide deposits (Q\({}_{4}\)del), with a thickness that gradually increases from the upper part of the slope to the slope's bottom. The deposits in the middle of the slope are thicker, while those on both sides near the ridge are thinner. The main material composition is gravel-bearing crushed stone silt, grayish brown to yellowish brown, slightly dense to dense, and slightly wet, with plastic silt. The mother rock of the crushed stone consists of siltstone, sandstone, and carbonaceous shale. The landslide has multiple sliding surfaces. The upper sliding surface is the contact zone between the Quaternary overburden layer and the fragmented rock mass of the bedrock, with a buried depth of 20 to 30 m and a sliding zone thickness of 1 to 1.5 m. The lower sliding surface is the contact zone between the fragmented rock mass and the bedrock (sandstone), with a buried depth of 10 to 30 m as well as a sliding zone thickness of generally 1 to 1.5 m,reaching a maximum of 3.1 m. It poses a serious threat to both the safety of the Three Gorges waterway and the lives and property of residents along the route [48; 49; 50]. Therefore, the Xinpu landslide in the Three Gorges Region of China was selected as the on-site monitoring point in this paper and multi-field data monitoring experiments were conducted on the underground rock and soil mass of the landslide so as to provide essential references for landslide hazard prevention and ecological environment governance in the region. Based on the unique geographical location and geological conditions of the Xinpu landslide, numerous landslide monitoring studies have been conducted based on the 'Space-Sky-Ground-Underground' monitoring technology, which provides significant references for the stability evaluation of the Xinpu landslide (Figure 18). To enhance the monitoring performance of InSAR technology in areas with dense vegetation (such as Xinpu), [PERSON] et al. introduced a framework using interferometric synthetic aperture radar (InSAR). This framework utilizes ICA-assisted intermittent MT-InSAR methods to achieve time-series deformation measurement in areas with seasonal vegetation changes. Compared to conventional methods, this method can achieve an average RMS improvement of up to 46.2% [51], which effectively improves the monitoring accuracy of InSAR technology in vegetation-covered areas. Thereby, real-time monitoring of landslides can be achieved. [PERSON] et al. conducted space-based monitoring of the Xinpu landslide using the UAV LiDAR topographic survey. The evolution process of the Xinpu landslide was divided into four stages based on the UAV monitoring data, including the shallow creep-crack extension stage, overall sliding-front edge bending deformation stage, sliding bending-front edge shearing stage and ancient landslide sliding-revival stage [52].