基于水资源约束的中国城镇化SD模型与模拟

China's urbanization SD modelling and simulation based on water resource constraints

中国城镇化正处于快速发展阶段,尽管经济和社会发展主控要素还在发挥重要作用,但水资源在生产、生活和生态方面发挥主控作用的局面愈益明显。在中国城镇化系统动力学(system dynamics,SD)模型基础上,从水资源供给、需求和水环境等层面将水资源作为主控要素嵌入原有模型中,拓展出基于水资源约束的中国城镇化SD模型,并对水资源利用进行了多情景模拟。结果表明:(1)系统存流量和灵敏度检验证明模型模拟效果良好,具有可操作性。(2)部门用水效率一定时,产业发展对水资源供需平衡的影响比人口增长更为明显。(3)在实行节水农业、节水工业、高生活需水、高生态环境需水和高再生水利用的综合协调方案中,2050年中国城镇化的发展约共需6789.70亿m^3水资源,基本实现水资源供需平衡。

Currently, China is at the critical stage of rapid industrialization and urbanization.Although the controlling elements of economic and social development are still dominating the process of urbanization, the role of water resources in terms of production, living, and ecology has become increasingly significant. However, there are still two urgent issues that should be dealt with. Specifically, the first research question is how to couple water resources, which is also a controlling element in urbanization, with economy and demography. Second, how to coordinate and optimize the relationship between urbanization and water resources utilization in China is supposed to be further explored. Thus, this study extends the existing China’s urbanization system dynamics(SD) by incorporating the key controlling element of water resources into the original SD model from the perspectives of water supply, water demand, and water environment. Then, based on the newly constructed China’s urbanization SD model, we simulate the water resources utilization in the future with multi-scenarios of China’s urbanization. The conclusions can be drawn as follows:(1) The system stock-flow test and sensitivity analysis demonstrate that China’s urbanization SD model based on water resource constraints is effective in simulation and operability.(2) When the water use efficiency of a certain sector keeps constant, the industrial development will exert more significant effects on the water supply and demand balance than population growth, typically in agricultural and industrial water demand.(3) According to the proposed scenario, which assumes the integrated and coordinated development with water-saving agriculture, water-saving industry, high domestic water demand, high ecological and environmental water demand, and highly reclaimed water utilization, China’s urbanization growth until 2050 will require approximately6789.70 × 10~8m^3 of water resources in total, consisting of 3642.65 × 10~8m^3, 1215.53 × 10~8m^3,1361.80 × 10~8m^3, and 569.72 × 10~8m^3 for agricultural demand, industrial demand, domestic demand, and ecological and environme ntal demand. The proposed scenario not only contributes to the stable and high-quality economic development and population growth, but also achieves a balance between water supply and water demand, which guarantees the water demand of residents’ daily life and the ecological environment as much as possible. Both the highly efficient and sustainable utilization of water resources and virtuous socio-economic development can be realized in this scenario. It should be one of the sustainable ways for China’s new urbanization in the future.