Study On The Influence Of Vegetation On Geological Hazards Growth Of Loess Plateau

Wuqi County, which is in the northwest of Yanan city in Shanxi province, locates in the region of loess plateau. The ecological environment of this area is one of the most vulnerable regions in our country and the special natural geography environment caused by the landslide,collapse and debris flow and other geological disasters take place frequently, which seriously threats people's lives and properties.In recently years, with the intensification of human being's engineering activities, the geological disasters present an aggravating tendency.Therefore, it is important to study on the correlation of vegetation and geological hazards growth of WuQi County.This paper combines with the detailed investigation task of geological disaster in Yan'an of Shan'Xi Province which issued by China Geological Survey Bureau in 2008. On the basis of the laboratory test and the detailed survey of the geological disaster in WuQi, it carried out research work on the correlation of vegetation and geological hazards growth of Wuqi County. First of all, we study regional geological environment, loess properties and vegetation characteristics of WuQi. Then through the research of the mechanism of biotechnical slope protection, such as the strength of herbs' root and the anchoring effect and the supporting effect of woody plants' root and the hydrologic effect of the biotechnical slope protection, analysis of the affect of vegetation on the geological disasters. Then this paper has an in-depth analysis to the characteristics of loess landslide and internal and external formation factor of landslide so that rainfall and human engineering activities were the main predisposing factor of loess landslide in WuQi. Again we has analyzed the re-development characteristics of geological disasters, obtained that large - medium-sized and medium - thick slide-based are the main geological hazards of WuQi. Finally, we have designed a slope and calculated the stability of the slope in a natural, saturated water and bare land, with vegetation. Then we use the software of FLAC for a particular slope. Then we based on our analysis of slope stability, further analyzed and summarized the vegetation on the impact of geological hazards of WuQi.