Risk Analysis And Assessment Of Flood Disaster In Poyang Lake Region

As both the frequency and the intensity of global natural disaster occurrences are increasing, the research on natural disaster risk is drawing more and more attention in the international community and domestic related field. Flooding is a one of the worst natural disasters worldwide. With the population growth, wealth accumulation and rapid progress of urbanization, the world is facing increasing risk of flood disasters. Losses that caused by floods are becoming more and more serious. It's widely accepted that relying on dikes and other flood control facilities to fully control the floods is not realistic. From flood control to flood risk management is becoming popular both in the study and the practice of Flood Control and Disaster Reduction home and abroad.Poyang Lake region is one of the most flood-prone areas in the Yangtze River watershed. Frequent floods not only threaten the safety of life and property, but also seriously restrict the economic and social development in this area. As the State Council officially approved "Poyang Lake Ecological Economic Zone" as a national strategy in December 2009, the rapid urbanization, population growth and the accumulation of economic and social development will further exacerbate the risk of flooding in Poyang Lake region.Flood risk analysis and assessment is the scientific and technologic basis of flood risk management. Based on the analysis of a large number of relevant literatures, the author summarized the system of the theory and methodology on flood risk analysis and assessment. Based on literature analysis, wavelet analysis, frequency analysis, Mann-Kendall test and other methods, this paper discussed both the hazard inducing environment and hazard inducing factors in Poyang Lake region. Through the establishment of evaluation index system of Poyang Lake region, this paper also assessed the flood risk of the area. Besides, the author established a risk assessment model based on information diffusion theory to evaluate the flood risk on agriculture in the Poyang Lake region. This study is aimed to improve the security level of flood protect in Poyang Lake region, as well as to provide technical support for the balanced and sustainable development of economy and society in the Poyang Lake Ecological Economic Zone.Here are the main achievements of this paper: (1)Summary on the system of theory and methodology on flood risk analysis and assessment;(2)Systematic analysis of the flood risk in Poyang Lake region;(3)Establishment of the flood risk assessment index system and flood risk evaluation in Poyang Lake region. Assessment results indicate that the risk orders of 10 counties in the area are: Poyang County> Yugan County> Duchang County> Xingzi County> Nanchang County> Jinxian County> Xinjian County> Yongxiu County> Hukou County> Dean County.(4) Establishment of the Poyang Lake agricultural flood risk assessment modelThe author calculated the potential loss of agriculture in Poyang Lake region and pointed out that the expectation of inundated farmland may reach about 375km~2.Through scenario analysis, the author also studied the loss rate of grain as well as the economic loss in different scenarios.