Water resources carrying capacity in Guangzhou city

摘要

The concept of carrying capacity has been proved to provide contribution to solve environmental problems. So, it is used widely in environmental planning and urban planning. Because cities are major users of scarce natural resources and the cause of serious environmental damage, assessing urban carrying capacity of water resources has bee emphasized. But there are some problems should be solution when it is used in urban water system. The key issues in estimation of carrying capacity are discussed by analyzing urban water system in this study. The first of them is the relationships in water system, economic system, social system and ecological system. How water quality and economic development impacts the estimation of water resources carrying capacity. The second is using variables which have close relations with urban planning to evaluate the carrying capacity. The third one is method to estimate carrying cavity. in the peeper, the system dynamic model has been built based on system analysis for urban water cycle. This model considers changes of water resources caused by changes of water quality and adjustment of economic structure, sues water resources and environmental investment as its major variables and confirms development costs of water resources by Logistic equation. Because data in the model are easy to obtains, it can be sued in urban planning and environmental planning widely. Furthermore,m because major variables of the model are usually described in urban planning, the model can be used to assess strategy of urban development. In the case study, the carrying capacity of water resources in Guangzhou city has been estimated by he model. Based on "tenth five years project of Guangzhou", some projects are built by scenario analysis and its carrying capacity of water resources has be calculated. From the rusts of simulating comparing, some conclusion have been get in the paper.