Abstract:
To scientifically evaluate landslide stability and formulate effective mitigation strategies, this study takes Qinzhou District,Tianshui City as the research object. Based on the analysis of regional geomorphology and landslide development characteristics,ten indicators:geological structure,disaster frequency,slope gradient and gradient change rate,slope aspect and shape change rate,elevation,gully density,vegetation index,rainfall,earthquake,and human activity were selected.The Analytic Hierarchy Process(AHP) was used to determine their weights,and GIS spatial analysis was combined to conduct a comprehensive evaluation of landslide susceptibility,vulnerability,and hazard. The results show that landslides in Qinzhou District are dominated by loess landslides and loess-mudstone landslides. Five high-hazard zones,two medium-hazard zones,and three low-hazard zones were identified. The high-hazard zones cover about 1,163. 1 km
2,contain 158 hidden danger points,making them key areas for disaster prevention and mitigation. On this basis,a comprehensive mitigation strategy featuring " management first,technical support,and combined prevention and control" was proposed. In high-hazard zones,measures combining monitoring and early warning,drainage and load reduction,retaining reinforcement,and ecological restoration were adopted. A typical slope in the Taijing-Yuquan high-hazard subzone was selected for six-month deep displacement monitoring.The cumulative displacements of five inclinometer holes ranged from 12. 4 mm to 30. 6 mm,all below the 50 mm early-warning threshold,indicating coordinated deformation and overall stability of the slope. The study demonstrates that the proposed mitigation strategy is technically feasible and practical,and can provide a scientific basis for landslide risk control and territorial spatial planning in Qinzhou District and similar areas.