基于天-空-地多源信息的水库岸坡时空变形特征分析OA

Baihetan Hydropower Station is the second largest hydropower station in the world.Since April 5,2021,when water impoundment began,the average water level has risen by more than 150 m,and during its operation,the water level fluctuated by about 60 m.The substantial increase and the periodic recession of the water level have induced multiple deformations along the reservoir banks.This paper focuses on Xiaomidi deformation mass in Baihetan Reservoir area,integrating data from multiple monitoring sources including optical satellite imagery,time-series interferometric synthetic aperture radar(InSAR),unmanned aerial vehicle(UAV)photogrammetry,ground surveys,three-dimensional deformation monitoring radar,and Global Navigation Satellite System(GNSS),to establish a"space-air-ground"monitoring network.Based on multi-source monitoring data from these platforms,the study analyzes the spatiotemporal deformation characteristics of Xiaomidi during the initial impoundment period in Baihetan Reservoir.Wavelet coherence is then used to investigate the coupling relationships among rainfall,reservoir water level,and displacement in different periods and at different cycles,revealing the dominant frequencies and lag effects.The results indicate that since the reservoir impoundment began in April 2021,Xiaomidi deformation mass has continued to deform under the combined influences of terrain,lithology,reservoir impoundment,and rainfall.The deformation exhibits a pronounced traction-type zonal characteristic,with the magnitude of deformation decreasing from the slope toe to the rear edge.The correlation and periodicity between Xiaomidi deformation and reservoir water level fluctuations gradually weaken and exhibit a time lag from the front edge to the rear edge.Rainfall,on the other hand,shows limited coherence only at the rear edge and on short-term time scales.Integrating multi-source monitoring data from satellite,aerial,and ground-based platforms,wavelet coherence analysis has formed a comprehensive technical system for spatiotemporal deformation analysis of landslides,significantly enhancing the capability to understand deformation mechanisms of complex geological bodies and providing important technical support for scientific prevention,control,monitoring and early warning of reservoir bank landslides.