Evaluation of Landslide Risk Using the a and IV Methods: A Case Study in the Zipaquirá–Pacho Road Corridor

This study develops a landslide susceptibility zoning map for the Zipaquirá–Pacho road corridor in Cundinamarca, an area prone to frequent landslides. Two statistical methods—Weight of Evidence (WoE) and Information Value (IV)—were used alongside various causal factors to generate the map using GIS software. A landslide inventory with 101 points was compiled through fieldwork and Google Earth image analysis. Of these, 70% were used to build the models, while the remaining 30% were reserved for validation, ensuring spatial representativeness. The resulting susceptibility maps classified the area into five categories: "very high," "high," "moderate," "low," and "very low." For WoE, 19.62% of the area was classified as "very high" and 19.71% as "high," while for IV, the respective values were 17.57% and 26.55%. Notably, 88% of the identified landslides occurred in "high" and "very high" zones. Model validation using the AUC (Area Under Curve) metric yielded an efficiency of 81%, confirming the reliability of both methods for landslide prediction. The study's findings are essential for supporting mitigation strategies and serve as valuable input for local authorities and stakeholders involved in risk management and infrastructure planning.