The Landslide-debris Flow Risk Assessment Of Primary And Middle Campus In Chuxiong

Landslide-debris flow disasters, as a common geological and meteorological mountain hazard, which is not only threaten people’s life and property, but also bring great damage for nature, society, resources and environment. Landslide-debris flow has a not wide impact range, but the frequency is very high, and along with the global extreme climate change and human unreasonable land use in recent decades, the probability, intensity and damage from the landslide-debris flow disasters shown a constant trend of rising. Chuxiong Yi Autonomous Prefecture (Chuxiong) is located in the middle of Yunnan province and primary part of central Yunnan plateau which has fragile ecological environment, and complex terrain, loose rock which are all private favorable conditions for the development of the landslide-debris flow disasters, in addition, Because of the short of refuge common sense, primary and middle school students are usually under the threat of landslide-debris flow disasters, that affect the normal education on primary and middle school students seriously in Chuxiong. Therefore, it is necessary to construct the landslide-debris flow disasters risk assessment of primary and middle campus in Chuxiong, which will provide a scientific basis for effective disaster prevention and reduce the losses from landslide-debris flow hazards for primary and middle campus.This paper according to the regional natural risk system theory, which is natural disasters is combined with risk of hazard-inducing factors, sensibility of hazard-pregnant environment and vulnerability of hazard-affected bodies, as basic theory. According to the process of "principle and method-factor analysis and screening-index construction-model implementation-disaster risk assessment". It starts from the access of and analysis of the spatial distribution about different sensibility factors which affect the landslide-debris flow disasters in Chuxiong, and combined with the geographical location of primary and middle campus in Chuxiong to construct the landslide-debris flow disasters risk assessment system of primary and middle campus in Chuxiong. Combined with analytic hierarchy process(AHP) and K-means cluster analysis, every indexes weight in each level of assessment system, and models of risky of disaster inducing factors, sensibility of hazard inducing environment, vulnerability of hazard affected bodies and risk assessment are constructed. Using assessment model and town assessment unit, risky, sensibility and vulnerability could be assessed, and then the risk could be reached of the landslide-debris flow disasters risk of primary and middle campus in Chuxiong.The main conclusions were as follows:1. Using GIS technology, this paper constructed the source database of landslide debris flow disasters based on GIS through muti-sourse information unit matching, space information discretization and parameterization in Chuxiong. It started from the basic natural conditions and induce power on landslide debris flow disasters formation, and then analyzed the main influence factors of landslide debris flow disasters. It constructed four layers risk assessment index system which including target layer, criterion layer, sub criterion layer, and index layer, and then fixed the weight of every indexes using AHP.2. The result of assessment about the risk of hazard-inducing factors showed that the senior risk zone of the landslide-debris flow disasters of primary and middle campus in Chuxiong, because of high extreme precipitation, is concentrate on Wuding, Yuanmou, Mouding, Lufeng, Chuxiong. Yiyi, Xishelu, Dutian all have high extreme precipitation and disaster frequency radio, which caused highest risk level. The low level of risk zone is concentrate in the Yongren, Dayao, Yaoan, Nanhua and Shuangbai, these areas have lower extreme precipitation and disaster frequency radio. Therefore, the risk level is low.3. The result of assessment about the sensibility of hazard-pregnant environment showed that the sensibility level of the landslide-debris flow disasters of primary and middle campus in Chuxiong is higher in the east than the west. The senior sensibility is concentrate on the Yuanmou. Chuxiong, Lufeng and Shuangbai, these areas have strong tectonic activity, fully developed river valley, serious eroded soil. The sensibility level of the most other area in Chuxiong is lower because of high altitude and undeveloped rivers, such as Yongren, Dayao, Yanan, Nanhua, Mouding and Shuangbai in the southeast.4. The result of assessment about the vulnerability of hazard-affected bodies showed that the higher vulnerability level of the landslide-debris flow disasters of primary and middle campus in Chuxiong is relatively concentrated on the developed towns of every city which has many primary and middle campus and higher concentration degree; For the most relatively undeveloped towns, the vulnerability is not very weaker because the distribution is concentrate relatively even with less campus.5. The result of the disaster risk assessment showed that the risk level of the landslide-debris flow disasters of primary and middle campus in Chuxiong is middle. The senior risk zone was mainly concentrated on the Wuding, Yuanmou, Mouding, Lufeng, Chuxiong, these areas all have high risk level. The sensibility level of Yuanmou, Mouding, and Chuxiong and the vulnerability level of Mouding, which had high level, is also reached senior level. The risk level almost is low in the Yongren, Dayao, Yaoan, Nanhua and Shuangbai because of lower risk level. Some towns reached middle level because of high vulnerability.