Spatially Fuzzy Comprehensive Assessment of Flood Hazard Risk in the Dongjiang River Basin

By analyzing the main factors of the flood disasters in the Dongjiang River basin on the index system of water,rainfall,runoff,typhoon,elevation,slope,population,GDP,land and road with ArcGIS software,this paper adopts the analytic hierarchy process(AHP) to determine the weights of various factors,and uses fuzzy comprehensive assessment(FCA) to obtain the flood disaster risk maps of Dongjiang River Valley.The results show that: The highest flood disaster risk zones in Dongjiang River Valley include Heyuan City,Huizhou City,Huiyang District,Dongguan City and Bao'an and Longgang which are inside the East River Valley,as well as the relatively economically developed areas in the lower and middle reaches of East River Valley.The relatively safe regions include the mountainous areas which are less economically developed in the lower and middle reaches of Dongjiang River Valley.High-risk areas are typical in the plain and close to the main road of the river.The results are consistent with the flood disasters in previous years,thus,conclusions are credible.