Study on Water Quantity and Quality-Integrated Evaluation Based on the Natural-Social Dualistic Water Cycle

For this study we constructed an integrated evaluation model of water quantity and quality that couples the supply-demand balance system, water consumption balance system, and a simulation model of water quality. In order to realize the dual water supply, the constraint equation of dual water supply has been added in the supply-demand balance system. The water pollution-induced water shortage quantitative identification approach and the evaluation index of the proportion between social economic water consumption and ecological water use has been put forward to evaluate the satisfaction degree of ecological water use and water quality based on simulations of water quantity and quality. This study utilizes an application of the water quantity and quality evaluation model in the main stream of the Huangshui River (Qinghai, China). The evaluation results provide support for future water resource development and management as follows: (1) the water quality-index water shortage rate of the entire area was 3.7% and in some local areas reached 25.7% (2) the proportion of ecological water use of each water resource partition were all more than 80% (3) although the ecological water demand in the rivers could be satisfied, the standard-reaching rate of water quality was very low due to the total pollutants not having been controlled.