城市化过程中的水资源供需情景模拟及水资源安全评价：以京津冀城市群为例

Beijing-Tianjin-Hebei urban agglomeration is an area facing resource-induced water shortage with significant contradiction between water supply and demand. Under the background of rapid urbanization and the recent “coordinated development” strategy, the urbanization pattern, industrialization pattern and ecological pattern in the Beijing-Tianjin-Hebei urban agglomeration will be changed, which will further lead to changes in the pattern of water supply and demand. Hence, this project focuses on water supply and demand balance and water resources security under this background in Beijing-Tianjin-Hebei urban agglomeration. Based on the cross-discipline of urban geography and water resources, this project employs many research methods including literature review, historical data analysis, mechanism analysis, case comparison, conceptual modelisation, scenario analysis and uncertainty analysis in order to address water resources evaluation. The pattern and mechanism of water resources supply and demand variations in the urbanization process will be revealed. Simulations of multiple water supply and demand scenarios will be run taking into account different uncertainty sources. Water supply and demand status and water security will be evaluated in different spatial scales, i.e., in the whole urban agglomeration and in individual provinces. Based on the results, suggestions that benefit water resources security in the urbanization process will be provided，and effective policy portfolios will be given to guide the urbanization process and “coordinated development”. The research results, on the one hand, will be used to support decisions towards the goal of harmonious development of urbanization and water resources in Beijng-Tianjin-Hebei urban agglomeration; on the other hand, will facilitate the development of the cross-discipline of urban geography and water resources.

京津冀城市群是资源型缺水严重地区，水资源供需矛盾突出。在快速城市化和京津冀协同发展背景下，京津冀城市群面临着城市化、产业化和生态格局的显著改变，这些改变将引起水资源供需格局的变化。因此，本项目将在此背景下分析讨论京津冀城市群的水资源供需平衡和水资源安全问题。立足城市地理和水资源交叉学科，通过文献回顾、历史数据分析、机理分析、案例比较、概念建模、情景模拟、不确定性分析等研究方法解决水资源评价问题：揭示京津冀城市群水资源随城市化进程的供需变化规律和变化机理；进行不确定因素影响下的水资源供需多情景模拟，从京津冀城市群和各省市尺度上分别评价水资源供需关系和水资源安全状况；给出城市化过程中有利于保障水资源安全的政策和技术建议，并提出有效的政策组合指导城市化健康发展。研究成果既为京津冀城市群城市化和水资源的协调发展提供科学决策支持，又服务于城市地理和水资源交叉学科的发展和提升。

京津冀城市群是资源型缺水严重地区，在快速城市化过程中，水资源短缺成为制约城市社会经济发展的瓶颈之一。本项目主要讨论京津冀城市群的水资源供需平衡和水资源安全问题。通过解析城市化过程中水资源供需关系演化规律，发现京津冀城市群常年面临极大的水资源压力，但近20年水资源短缺状况有逐步减缓趋势。巨大的水资源压力带来了地下水超采、生态环境退化、社会经济发展受阻等多项负面影响。提出采用结构分解分析方法量化不同社会经济与自然要素对水资源短缺压力年际变化的作用，发现用水效率提高、南水北调、产业结构升级为水资源短缺压力减缓的主要原因，水资源量的年际波动带来水资源短缺指数的随机变化。北京、天津、河北水资源短缺变化特征呈现出差异性。在虚拟水贸易框架下分析京津冀城市群与外部的水资源供需关系，发现北京、天津从外部输入大量虚拟水，对外部水资源的依赖性强，河北输出大量虚拟水，为京津冀城市群及其他地区供给水资源，加剧了当地的水资源短缺。考虑自然与人类活动等多个不确定因素，建立水资源供需关系模拟概念模型，预测不同情景下京津冀城市群水资源安全状况，发现即使在最乐观的情景下，未来京津冀城市群仍然面临巨大的水资源供需压力。在乐观的情景下，京津冀城市群水资源短缺压力呈现逐年减小趋势，而在不乐观情景下，京津冀城市群水资源短缺压力表现出上升趋势。在研究结果的基础上，给出城市化过程中有利于保障水资源安全的政策和技术建议。研究成果为京津冀城市群城市化和水资源的协调发展提供科学支持。