基于人水关系的京津冀城市群水资源安全格局评价

京津冀城市群是我国乃至全世界人类活动对水循环扰动强度最大的地区之一,水资源过度开发利用不仅严重影响生态环境安全,而且制约着经济社会的可持续发展。基于人水关系协调视角,从水资源本底条件、水资源开发利用程度、水资源开发利用效率等3个方面建立了水资源安全综合评价指标体系,并根据国内外发展经验和相关标准确定了评价标准阈值,使得评价结果在不同的时空尺度上均具有可比性。然后通过熵技术支持下的层次分析法和多目标模糊隶属度函数,对2000—2014年京津冀城市群水资源安全的时空格局进行了定量评价。结果表明:(1)整个京津冀城市群的水资源安全指数多在0.2—0.4之间,属于不安全类型,但总体向临界安全类型转变;(2)各城市的水资源安全指数在时空尺度上表现出较大差异,总体表现为南低北高且随着时间的推移普遍提高的格局;(3)整个京津冀城市群及各城市水资源安全指数的次级指标在时空尺度上也表现出一定的差异性和地域一致性,它们交互作用,最终综合决定着水资源安全指数的时空变化。

Evaluation of water resource security patterns in the Beijing-Tianjin-Hebei urban agglomeration based on human-water relationships

The Beijing-Tianjin-Hebei urban agglomeration is one of the most water-deficient regions in China and globally owing to intense human activities. Overexploitation of water resources has greatly affected the eco-environmental security, and restricted the sustainable development of the socio-economic system. Regarding the coordinated development of human-water relationships, a comprehensive evaluation index system for water resources security was constructed, which was composed of three criterion layers, i.e., natural endowment of water resources, exploitation and utilization degree of water resources, and exploitation and utilization efficiency of water resources. The thresholds and grading standards for each specific indicator and their integrated indexes were set according to the experience of developed countries and regions, so that the evaluation results could be compared spatially and temporally. Subsequently, we used an Analytic Hierarchy Process (AHP) model reformed by entropy technology to calculate their weights, and establish a multi-objective fuzzy membership function to calculate the normalized values. We used the statistical data of 13 urban regions in the Beijing-Tianjin-Hebei urban agglomeration during 2000-2014 to analyze the spatiotemporal pattern of water resources security. The results showed that: (1) for the whole region of the Beijing-Tianjin-Hebei urban agglomeration, most of the water resources security indexes were between 0.2 and 0.4, which were regarded as unsafe type during the period. However, they tended to become larger and the security type became critically safe; (2) various cities in the Beijing-Tianjin-Hebei urban agglomeration had different water resources security indexes. Generally, they were smaller in the South and larger in the North; most became larger during the period; (3) the integrated indexes of the three criterion layers also had a high degree of regional consistency and disparity. They interacted with each other spatially and temporally, and impacted the spatiotemporal pattern of water resources security in the Beijing-Tianjin-Hebei urban agglomeration.