A Preliminary Assessment of Landslide Occurrence in Relation to Slope Angle in the Bharmour Development Block, Himachal Pradesh
DOI:
https://doi.org/10.48165/prakriti.2026.3.02.08Keywords:
Bharmour, frequency distribution, Himachal Pradesh, landslides, slope angleAbstract
This study investigates the relationship between slope angle and landslide occurrence in the Bharmour Development Block, Himachal Pradesh, India. Using a landslide inventory of 1,511 events and a DEM-derived slope map, the Frequency Ratio (FR) method was employed to quantify the association between slope classes and landslide occurrence. The results show that although 58.64% of all mapped landslides occurred on very steep slopes, the highest Frequency Ratio (2.39) was recorded for gentle slopes, indicating a disproportionately high landslide occurrence relative to their areal extent. These findings suggest that slope angle alone does not fully control landslide occurrence in the study area, and that additional landslide conditioning factors, such as lithology, proximity to roads, land use, and rainfall, are likely to play important roles. The study provides a useful preliminary assessment of landslide susceptibility and demonstrates the importance of normalised measures, such as the Frequency Ratio, for understanding landslide distribution in complex Himalayan terrain
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