Research On The Assessment Of Flood And Waterlogging Risk In The Zhejiang Province Based On Remote Sensing And Geographic Information System

Flood and waterlogging disaster is one of the serious natural disasters,which has the greatestextent, hazardness and the highest frequency in all kinds of natural disaster and poses danger tohumans all the time.The risk assessment of flood and waterlogging is very important for preventingand mitigating disaster. In this paper the Zhejiang Province is used as the study area. On the base ofintegrating remote sensing images, gridded geographic data and gridded socio-economic statisticaldata, flood and waterlogging risk assessed by using the functions of GIS in data processing, spatialanalysis and model building.Firstly, using historical flood and waterlogging disaster MODIS data extracted from thedisaster to assess preliminary risk. The MODIS images have a long historical time series, wideswath and can be acquired freely, which is an important data in risk assessment of the disaster,because of MOIDS image data with time series is long, wide range of imaging, freely available,using MODIS image extracted in zhejiang province during the range2003-2012flood andwaterlogging season.In this paper, based on the function of spectral analysis, band math, decisiontree, the paper develops a method to extract flood and waterlogging by using MOD09Q1production. On the basis of water extent, the inundation frequency of flood and waterlogging iscalculated.Secondly, the thesis mainly make flood hazard, exposure, vulnerability and disasterprevention and mitigation capacity to be the primary index of flood and waterlogging disaster inzhejiang province.The secondary indexes mainly selected the elevation data, maximum three daysof rainfall, drainage density, population data, GDP data, young and old population, cultivated landratio, flood control standard, and waterlogged, density of hydrological stations, hospital beds,residents per capita deposit, per capita local fiscal revenue data, fifteen totally, the use of ArcGISfor data processing and analysis, getting fifteen1km1km grids handling of raster data indexdistribution of the disater risk assessment in zhejiang. On this basis, using analytic hierarchyprocess (AHP) to determine the index weight, and then the fuzzy comprehensive evaluationmethod (FCA), the function of ArcGIS modeling analysis of flood disaster risk. Lastly, the results of assessment of flood and waterlogging risk represented with two diffirentspatial scales-gird and administrative unit at the country level in this paper. From the assessmentmodels, the degree flood and waterlogging risk is increased from inland to the coastal areas, thehighest risk areas are mainly located in the plain area of Zhejiang coastal: Huzhou city, Jiashancounty, Jiaxing city, Pinghu, Haiyan county, Haining, tongxiang city, Cixi city, and Shaoxing city.The higher flood and waterlogging risk is distributed in Changxing country, Deqing county,Hangzhou city, Yuyao, Shangyu city, the urban areas of Ningbo, Taizhou city, Wenling city. TheShaoxing county, Linhai city, Ruian, Yueqing, Zhejiang Yuhuan, Pingyang county have mediumflood and waterlogging risk. The others region with a low flood and waterlogging risk.