Evaluation of Water Resources Security in the Urban Area and Regulating Methods Based on DPSIR: A Case of Zhangye City
基于DPSIR概念的城市水资源安全评价及调控

Urban water security is an important part of urban ecological security, and it plays an important role in the sustainable urbanization development process of city and region. Using the framework of "driving force-pressure-state-impact-response"(DPSIR)and combining the theories of water supply allocation, water pollution control and water security management of continental rivers, this paper has constructed a DPSIR framework of river basin water resources management from the point of view of system dynamics. From the perspective of systematic analysis, the model is a concept model of evaluation index system that is extensively used in environmental research as well as a general frame that is used to organize information about environmental status. By taking the middle reaches of Heho in Zhangye City as an example, this paper has established a mathematical model of driving factors, pressure, influence and human activity of water resources system changes, and quantitatively analyzed the interaction among population-economy-water resources of water resources system and the feedback mechanism. The results show that, from 2000 to 2007, the water system of Zhangye city tended to be a virtuous cycle; the main driving forces of deterioration of water resources system are population growth, social and economic development, and the enormous pressure on water resources system is caused by increases of agricultural and industrial water demand, and the aggravation of industrial and living water pollution. Finally, according to results of the analysis, the main adjustable indicators in the management of water resources in a town have been proposed, thus providing a theory basis for the management of city water resources. However, the research also has shortages and needs to be improved in the following aspects: 1) Explain further the relationship among ingredients of DPSIR model, build a more detailed model of the system, and use the statistical data of water resources to predict the trend of city water safety; 2) Establish a model platform of safety warning of urban water resources to control and test the changes of city water resources system, and provide timely reasonable scientific basis for the management of urban water resources security system.