Water resources carrying capacity of wetlands in Beijing: Analysis of policy optimization for urban wetland water resources management

Abstract Based on analysis of the wetland water resources system in Beijing city, this paper established a system dynamics (SD) model for the water resources carrying capacity (WRCC) in Beijing city. Using a computer simulation of the SD model, the variation trends from 2006 to 2030 in population, economy, water supply and demand, and pressure on the water environment were derived for Beijing, from which 12 core variables of the model were chosen as the WRCC evaluation indices. Five cases were designed in this study. The results indicate that the WRCC will continue to decline annually by following the status quo (Case 1), since the water environment will have difficulty in supporting the long-term social and economic development of Beijing. The status quo of Beijing’s socioeconomic development is therefore not sustainable. In order to address this problem, five optimization cases were put forward to improve the WRCC, and the carrying capacities and trends of the cases were compared and analyzed. Under Case 5, the WRCC (0.8 in 2030) will increase by 50%, compared to that in Case 1 (0.4 in 2030), while the water supply and demand ratio will be 20% higher than the average, and the water pollution will be 35% lower than the average in 2030. According to the analysis results, in order to guarantee sustainable utilization of water resources and social economy development in Beijing, it is necessary to increase water saving policies and pollution control investment in the future. Corresponding measures will need to be taken to ensure the implementation of water saving strategies to improve the water environment.