Study Of Rural Areas' Flood Vulnerability

Flood disaster is one of the most important natural disasters in China,and the economic loss caused by flood accounts for about 3.5% of the total output value of the national economy yearly.China's rural economic development is relatively backward,and industry is relatively single.Standard for flood control is relatively low,and the villagers' consciousness of flood control is relatively weak.Due to the above reasons,the flood is very easy to cause casualties and economic losses.In view of the weakness of the research on flood control and disaster mitigation in rural areas of China,this paper examined flood submerge range in the Wanquan river downstream using DEM and hydrological data.The research units for this paper are villages and towns.Firstly,for each of the unit,values of 16 indices reflecting the social economy,population structure,housing and road loss were computed.Secondly,based on the indices,exposure,sensitivity and adaptive capacity were quantitatively studied using fuzzy synthetic evaluation.The overall vulnerability of each unit was calculated and plotted in GIS to obtain the vulnerability distribution map.The major study contents and conclusions are as follows.(1)The towns and administrative villages' flood vulnerability assessment system is established,which is suitable for the rural areas of China.In consideration of the representation and the availability of the index,we selected 16 indicators to reflect rural areas' flood vulnerability in scale of town.Combined with the vulnerability analysis of administrative villages,the two level of vulnerability assessment system was established,and the vulnerability distribution map was obtained.This is a development and innovation for the previous flood risk map,and it is of operational and practical significance.(2)Two-dimensional hydrodynamic model was established to quantify the exposure of the study area,which covered property,roads and personal security aspects.For the first time,the combined effects of flow velocity and water depth on safety of person were analyzed in the exposure assessment,which made it more comprehensive.This method provides a concrete and feasible calculation model for the analysis of the degree of exposure in rural areas.(3)Taking Wanquan River Downstream as an example,the calculation and analysis of the vulnerability of the rural areas in this area were carried out.Further research was made based on the analysis result,which mainly included the study of the change of the time scale of vulnerability and the comparative analysis of different analytical methods.A new index of vulnerability analysis was proposed,which was used to reflect the internal heterogeneity of the evaluation object.