Analysis of Water Resources Carrying Capacity of Coastal Cities along the Yangtze River Based on PSR Model

The coastal cities along the Yangtze River are relatively rich in water resources but the economy is developed, therefore the contradiction between economic society and water resources still exists. According to the characteristics of coastal cities along the Yangtze River, this paper constructs an evaluation index system for water resources carrying capacity based on the Pressure-State-Response(PSR) framework. Based on typical examples of Nantong City's 2010-2018 relevant index data, using the Analytic Hierarchy Process (AHP) model and with the help of YAAHP software, the following conclusions are obtained: 1) There are pressure state response mechanisms in each element of the water resources carrying capacity system of coastal cities along the Yangtze River. The key to the operation of the system is the limit of water resources carrying capacity. 2) Domestic water demand has the greatest impact on water resources carrying capacity. Domestic water demand has the greatest impact on the carrying capacity of water resources, but in the allocation of water resources, it is important to optimize the production water use of the industrial economy and provide sufficient funds to guarantee.3) During the period of 2010-2018 in Nantong City, with the development of industrial economy, the discharge of industrial wastewater was significantly reduced. Moreover, the investment in the treatment of industrial pollution, especially industrial waste water pollution, has been significantly increased, and the carrying capacity of water resources has been constantly optimized.