Analysis Of Temporal And Spatial Characteristics Of Landslide Disaster And Landslide Susceptibility Assessment In Chongqing

Chongqing is a city with a high incidence of landslide disaster, which causes a large number of casualties and economic losses every year. Based on the historical records of landslide disaster, this paper analyzes the spatial-temporal characteristics of landslide in Chongqing. Since 1980, the number of landslide in Chongqing has increased significantly, and the increase mostly occurred in May to September, especially in July. More than 80% of the landslides are triggered by rainfall, while other influencing factors are nature disasters and human activities. The high density of landslide in Chongqing are the urban areas and Wanzhou District as well as Zhongxian segment in the Three Gorges area. The high-occurence disaster zone for landslides is changed from the northeast to southwest.Using the landslide records,this paper analyzes the occurrence condition of landslide. And this paper extracts the information of the impact factors from DEM data, MODIS NDVI data and 30-meter Global Land Cover Dataset. Then I use the method of weighted information value to determine the rights of the impacts factors. The susceptibility evaluation is carried out by the combination of these impacts factors. The conclusions of this paper are drawn as following:(1) Using the landslide records from 1950 to 2011, this paper anaylzes the spatial-temporal characteristics of landslide by different scale and triggers. Through studying the the spatial distribution of landslide in Chongqing City, We know the expansion and change of the high incidence of landslide area of Chongqing city.(2) Refer to previous research results, this paper creates a landslide hazard evaluation index system, select geological lithology, the direction and the structure of slope, the role of water, the index of ndvi, and the land use type as a major impact indicators. Building spatial database of landslide disaster of Chongqing city using the extracted information of the impact factors from other database.(3) Based on the impact factors database, This paper gets the rights of each impact factor by the information quantity method. The susceptibility evaluation is developed by the combination of the rights of these impact factors and divided into five regions.