Evaluation of Geological Hazard Susceptibility in Huixian City Based on AHP-IV

This study presents a systematic evaluation of geohazard vulnerability in Huixian City, employing an informative model based on gully units integrated with hierarchical analysis (AHP-IV) to more accurately depict the geomorphic characteristics of geohazards. Utilizing ArcGIS and SPSS software, this study identified nine key evaluation indices: slope, Melton ratio, gully density, hazard point density, degree of undulation, rock group, normalized vegetation index (NDVI), soil erosion potential index (SPI), and multi-year average rainfall, facilitating a comprehensive assessment of geohazard vulnerability. Results showed that 36.13% of the study area was covered by zones with very high and high susceptibility., exhibiting concentrated geohazard development, while low susceptibility zones harbored fewer geohazard sites, consistent with actual distribution patterns. To validate the assessment results, this paper employed the frequency ratio model and ROC curve analysis. The frequency ratio demonstrated an increasing trend with escalating risk levels, with the very high susceptibility zone exhibiting significantly higher frequency ratios compared to the low susceptibility zone. Furthermore, the evaluation model achieved an AUC value of 0.871, indicative of its high precision and reliability, thus offering robust insights for geological hazard monitoring and early warning systems in Huixian City. This study not only enhances the practicality and guidance of geological hazard assessment but also furnishes a critical scientific foundation for geological hazard prevention and control efforts.