A DYNAMIC MODEL OF WATER SECURITY LEVEL IN BEIJING

As the constant development of China's economy and population increases, the water shortage is becoming more and more severe. Many regions are now facing water resource crisis. In order to solve this problem and offer a dynamic evaluating scheme, this paper makes qualitative analysis of water resources and separates it into two parts——"supply" and "demand", according to the categories on National Bureau of Statistics of China. And then, it makes more specific categories in each part and uses the data to get fitted graphs and equations. Then, it establishes differential equations and analyzes the collected data to develop a dynamic mathematical model of water resource to assess whether a particular area has the ability to meet the demand of water usage. And we also use past data and facts to test our hypothesis. At last, we choose Beijing as the object of study, use this model to assess the water security level and obtain the future situation of water resource in Beijing in the following 10 years. Beijing is the capital of China, situating in the north of China. It is somehow different because the government is running a "south water to north" plan to help Beijing offer enough water to its citizens. Also, in 2008 Beijing is the host city of the 29^th Olympic Games. So this influences the industrial water emission, which we explain in the paper in detail. Based on the analysis, we put forward two policy proposals to solve the problem of water crisis: either to introduce new policy to restrict the water sewage or to increase the water input from other regions.