Early Detection and Monitoring of Potential Landslides in Danba County Based on the Space-Air-Ground Investigation System

Objectives In view of the problem that it is difficult to identify the high hidden landslides by traditional ground investigation methods, the author's team have proposed the space-air-ground investigation system of landslide detection and monitoring. It has been applied nationwide with good results.However, there are few academic reports about it. In the study area of Danba County, where landslide disasters are frequent.Therefore,the detection and monitoring of potential landslides based on the space-air-ground investigation system was carried out.

Methods First, stacking-interferometric synthetic aperture radar(Stacking-InSAR) and small baseline subsets-InSAR(SBAS-InSAR) were combined with high-resolution optical remote sensing to achieve a wide-area census of active landslides in the whole study area, and the results of Stacking-InSAR and SBAS-InSAR were compared and analyzed. Second, light detection and ranging (LiDAR) technology and unmanned aerial vehicle aerial photography technology were used to conduct a detailed investigation of landslides in high-risk areas around Danba County, and further verification of major landslides through on-site investigation. Finally, SBAS-InSAR technology was used to monitor and analyze the deformation of typical landslides.

Results 41 active landslides were detected in the study area by using the space-air-ground investigation system. They are mainly local resurgence of large ancient landslide accumulations under long-term gravity, river scouring and human engineering activities, etc. Most of the landslide deformations have a good correlation with rainfall.

Conclusions In the process of identifying landslides by using the space-air-ground investigation system, it is necessary to give full play to the advantages of each technical means.