Research On Factors Analysis And Risk Assessment Of Flash Flood In Shaanxi Province

Flash floods not only restrict the socio-economic development,but also seriously threaten people’s lives and property safety.To carry out the prevention and control of flash floods is an important decision made by the State Council.Shaanxi Province set up a project team for flash flood disaster prevention and control,and actively carry out the work of flash flood disaster prevention and control in Shaanxi Province,which has achieved fruitful results.However,there is a lack of systematic analysis and research on the survey result data,and the data are not fully utilized.In this paper,we adopt relevant research methods,dig deep into the result data,and conduct relevant analysis and research on flash flood disasters in Shaanxi Province,which fully reflects the value of data and has important guiding significance for the prevention and control of flash flood disasters in Shaanxi Province.The main research contents and results of the paper are as follows.(1)Analyze and investigate the spatial and temporal distribution patterns and influencing factors of flash flood disasters in Shaanxi Province.Combining the flash flood disasters in Shaanxi Province from 1949 to 2015,the results of the historical survey of flash flood disasters in Shaanxi Province were sorted out and counted,and the spatial and temporal distribution patterns of flash flood disasters in Shaanxi Province were analyzed from both temporal and spatial scales,respectively.The distribution of flash flood disasters in Shaanxi Province gradually increases from north to south,with the pattern of patchy and banded distribution.Flash flood disasters in Shaanxi Province are widely distributed,regionally distinct,frequent,seasonal,easy to occur suddenly,difficult to predict,quick to occur,and hazardous.The distribution pattern of flash floods is influenced by rainfall,subsurface conditions,human activities and other factors.(2)Analyze the driving forces of flash flood disaster-causing factors in Shaanxi Province.Nine types of driving factors related to flash floods in Shaanxi Province were selected,and the degree of influence of each driving factor on flash floods was quantitatively analyzed,and the driving force analysis of the driving factors of flash floods in Shaanxi Province was carried out by using the geographic probe model.The results show that flash floods are the result of multiple factors acting together;rainfall factor is the direct factor and excitation condition for inducing flash floods,topography and geomorphology are the material basis and potential conditions for the occurrence of flash floods,and unreasonable human activities exacerbate the degree of flash flood hazards.Multiple factors acting together will strengthen the occurrence and danger degree of flash floods and affect the spatial distribution of disasters.(3)Analyze the degree of risk of flash floods in Shaanxi Province and conduct risk evaluation.Using fuzzy hierarchical analysis and ArcGIS spatial analysis,risk evaluation indexes were selected from both natural and social factors to further analyze the distribution of flash flood hazard and vulnerability distribution in Shaanxi Province and each region,and to conduct a comprehensive evaluation study of flash flood hazard risk.The results show that the risk of flash floods in Shaanxi Province gradually increases from north to south;the vulnerability is greater in Guanzhong than in southern Shaanxi than in northern Shaanxi.The degree of risk of flash floods in Shaanxi Province gradually increases from north to south,and the protection of Qinba Mountain area in southern Shaanxi should be strengthened in particular.The evaluation results and risk map can provide a scientific basis for the prevention and control of flash floods in Shaanxi P rovince.The analysis of driving factors and risk evaluation of flash flood disasters in Shaanxi Province will be beneficial to upgrade some parts of the provincial flash flood disaster monitoring and warning platform;to carry out the construction of flash flood disaster prevention and control projects;to carry out the compilation of flash flood disaster image data to improve the construction of group measurement and prevention system;to continuously improve the level of comprehensive flood disaster defense to meet the requirements of economic and social development;to consolidate and improve the built Non-engineering measures system.The work of flash flood risk analysis in Shaanxi Province has important guiding significance for the prevention and control of flash floods in various regions of Shaanxi Province.