Model of landslide hazard zonation and its effective factors using quantitative geomorphology (Case Study: Sanich region, Yazd)

Landslide can be considered as one of the important challenges of nature that affects natural areas and human societies. Several factors such as physical characteristics of the watershed, geology, soil structure, meteorology and hydrology are the most important environmental factors affecting in the landslide event. In order to reduce damage, landslide zoning have significant role in management of this phenomenon and planning. Many methods have been studied and used for landslide zoning.  For landslide hazard zoning, geomorphometry parameters used in surface digital modeling, are applied in this study. For this purpose, by using visual interpretation of aerial photographs and clear landslide position; map was made in the GIS. Then, by using a digital elevation model, geomorphometry parameters of landslides area, were extracted with a dense random sampling network. The decision tree is used to analysis of these parameters importance. Then, by using the geomorphometry parameters, landslide maps were extended for all the area. The results evaluation shows that the landslide digital zonation using the geomorphometry parameters have 88.2% accuracy. 20% of the data were abandoned for the test. Model results accuracy evaluation on the test data was 74.4 percent. Among the used parameters, parameters slope with 100 percent,   total curvature with 79% and a general curvature with 11% have greatest impact and it can be most important in the model.