Analysis Of Flood Risk Evaluation In Jinjiang Basin Based On Gis

Flood control and hazard mitigation is one of the eternal theme of human society. With the inevitability of flooding, the only thing for people to do is to make manage for flood, but to resist the occurrence of floods. Only in this way can we avoid risks and minimize losses when the flood occurs. A great support of the flood control and hazard mitigation is Flood risk assessment, which is the foundation and an important prerequisite of flood risk management. And it's of great significance for the frequently flooding regions.In all sorts of flood disaster, rivers flooding is the main component. Located in the southeast coastal fujian, jinjiang river basin of quanzhou is a one of frequently flood areas. Therefore,this paper is build the jinjiang river flood risk evaluation model which from the Flood theory viewpoint. Building hierarchy of flood risk and index quantification with the hazard-formative factors, subsquently environment,and hazard-affected body in this model. Using the basic geographic data, rainfall data, the background of social and economic statistical data, with the comprehensive use of analytic hierarchy process (AHP), multilayer fuzzy comprehensive evaluation method (MFSE) and GIS spatial analysis and modeling technology, the model is established more Objective. Assess the jinjiang river flood risk of comprehensive evaluation,and analysis the flood risk evolution. Main results show that:Jinjiang River Basin flood risk associated with a higher degree of rainfall, topography and river network is followed. The terrain and river net take more effect to the flood risk on the downstream and flat area. Jinjiang river flood risk distribution is gradually increase from northwest to southeast, the risk is higher on the downstream and the estuary runoff.The high risk region and middling-high risk region combined 40.84% for greater proportion in the whole basin, the main distribution of these region is Locally in the whole city Li, Jinjiang northern,the northwestern and central nanan, the east of AnXi and YongChun southeast. The risk comprehensive index value of flooding counties from high to low, is jinjiang district, nanan city, FengZe, NanAn, DeHua, YongChun,LuoJing, and AnXi.The change of Jinjiang river flood risk level is not obvious during 2000 to 2006. The area of the high risk region and middling-high risk region has increased, and the rest were decreased, but the magnitude is not large. The sharpest change in the risk range is the high-risk region. The increased area of flood risk account for 24% of the whole basin. And the basin flood risk index variation mean for 0.0124. The increased risk to the average is FengZe area, Li area,and jinjiang,the three places' flood risk mean amplitude are all far more than the whole basin.