Landslide hazard and risk map for road network using remote sensing and GIS: A case study of Xin Man district, Ha Giang province

Abstract

     Xin Man district in the South west Ha Giang has high landslide hazard. However, the available information on landslide in Xin Man district is still limited. We constructed the essential spatial database of landslides using GIS techniques. The quantitative relationships between landslides and factors affecting landslides are established by the Certainty Factor (CF). The affecting factors such as slope, elevation, landcover, geology, road distance, lineament distance, drainage density are recognized. By applying CF value integration and landslide zonation, the most significant affecting factors are selected. By using RS&GIS technology landslide occurrences on all these factors have been analyzed. The vector based GIS has been used for digitizing to produce thematic maps, as analysis for study was based on the pixel based information therefore Raster based GIS has been used for the analysis. Pixel based calculation was made by using the CF value Model. By using the CF model we obtain the CF value for all classes al all factor maps. On the basis of these CF value all factor maps are recoded and matrix analysis was perform to produce a Landslide Hazard Zonation map.