Study On Analysis Method In Assessment Of Water Resources System Vulnerability And Application Under Changing Environment

With the development of society and economy and climate change, the global environment is changing and the problems of water resources system become much serious, such as water shortage, supply-demand contradiction and water pollution. To cope with these issues, water resources system vulnerability assessment is needed, which can be used to understand and measure the vulnerability of water resources system in different regions and provide evidences for the protection, restoration and utilization of water resources.Water resources system vulnerability assessment is an important part of water resources system security analysis. Water resources system vulnerability reflects the stability of water resources system. It is possible to measure the change of the quality and quantity of water resources, and the increase of water resource disequilibrium, drought and food disasters and so on, under the changing environment. However, there were few of researches about water resources system vulnerability, especially considering the changing environment. Among former researches, the evaluation standard is imprecision and the theory of water resources system vulnerability assessment in these researches is still under dispute. Therefore, this study is the research on analysis method in assessment of water resources system vulnerability and application under the changing environment. The major research and contents are as follows:(1) This study establishes the theory framework of water resources system vulnerability assessment according to the characteristics of water resources system, and analysis the water resources system vulnerability under climate change and human activities. To establish the assessment index system, the feature of climate change, water resources system, social economy and human activities should be considered.(2) This study selects the first-grade water resources regions as study areas, and applies the approach of the water resources system vulnerability assessment model bases on fuzzy pattern recognition. The results show that Hai River Basin and Yellow River Basin belong to utmost vulnerability, Liao River Basin, Songhua River Basin, Northwest River Basin and Huai River Basin belong to high vulnerability, Yangtze River Basin, Southwest River Basin and Zhujiang River Basin belong to middle vulnerability, however, Southeast River Basin belong to low vulnerability. This study also uses the projection pursuit and set pair analysis in water resources system vulnerability assessment to make sure the accuracy of assessment results by using fuzzy pattern recognition.(3) This study analysis the changing environment under different greenhouse gas emission scenarios (A1B、B2、A1) bases on CSIRO in China in the2020and2030level years, and predicts the water resources system vulnerability using fuzzy pattern recognition. The results show that the water resources system vulnerability will be lower in the future in China with the annual precipitation is increasing and water supply capacity is improving, however the vulnerability in north China is higher than that in south China.(4) According to the results of water resources system vulnerability assessment and the characteristics of water resources system, this study proposes countermeasure of lower the vulnerability of water resources system in different basins.