Mapping of Landslide Hazards Using Remote Sensing and GIS in Gandaki Province, Nepal Nabaraj Neupane*1, Bikash Sherchan2, Krishna Prasad Bhandari3 and Sujan Subedi3
*1 Department of Civil Engineering, Pashchimanchal Campus, Tribhuvan University, Nepal
2Department of Geomatics Engineering, Pashchimanchal Campus, Tribhuvan University, Nepal
3Center for Space Science and Geomatics Studies, Pashchimanchal Campus, Tribhuvan University, Nepal
Abstract
Because of the the rugged topography, fragile geology and heavy rain precipitation pattern, landslide hazards pose a major threat in the Himalayan Region. Gandaki Province experiences the highest rainfall in Nepal and its fragile geology alleviate the probability of landslide occurance every year. The aim of this study is to analyze the landslide hazard and to present the results using a Geographic Information System (GIS) based on hazard risk zonation applying Analytical Hierarchy Process (AHP) techniques in Gandaki Province, Nepal. Hazard risk mapping was performed based on twelve conditioning parameters under four groups i.e., topographic factors (Elevation, Slope, Land Use Land Cover, and Profile curvature), hydrological factors (Proximity to stream, Precipitation, Flow Accumulation, Drainage Density, and Topographic Wetness Index), geological factors (Geology and Fault lines) and infrastructure factor (Proximity to road). Hazard risk maps were then classified into five classes: very low, low, moderate, high, and very high risks. The result then analyzed using GIS based on applying AHP technique. The historical date of landslides were validate by overlaying to the hazard risk map. The validity and accuracy were tested by. The calculated AUC (Areas Under the Curve) value 0.792 in the ROC (Receiver Operating Characteristic curve) indicating good accuracy during validation. The hazard risk maps were produced and were classified into five classes: very low, low, moderate, high, and very high risks. The Landslide Risk Map is used for disaster risk reduction, land use planning, and early warning systems.
Keywords: AHP, GIS, Hazards, Remote Sensing, Risk Zone
