基于WPI模型的重庆市水资源安全分析

为综合评价重庆市水资源安全情势,分析多重背景下水资源安全影响因素,以WPI模型构建水资源安全评价指标体系,该体系分为5个子系统资源(R)、途径(A)、效率(U)、能力(C)和环境(E)。采用加权函数法计算1997—2013年重庆市水资源安全综合评价指数和5个子系统得分值,并利用因子分析法进行对比分析;建立水资源安全因素判定模型,对子系统进行优等、中等、劣等因素划分。结果表明重庆市水资源安全值呈阶梯式上升,趋势系数为0.022 8 /a,水资源安全状况趋于好转,并且与因子分析对比结果基本一致;但各子系统时序变化差异较大,途径和能力子系统分值逐年上升,资源和环境子系统分值比早年有所下降,该阶段的效率子系统分值变化不大;因素评判结果显示,途径因素和能力因素随着时间推移而不断提高,从劣等因素变为优等因素,但资源和环境因素却逐渐演变为重庆市水资源安全的劣等因素,效率因素降为中等因素。未来重庆市水资源安全存在一定风险,需加强水资源管理和水环境改善,提高公民节水意识来加以防范。

Analysis of Water Resources Security in Chongqing City Based on WPI Model

The aim of this research is to comprehensively assess the situation of water resource security in Chongqing city and analyze the influencing factors in multiple background. We built an assessment index system of water resources security based on WPI model. The system consists of five subsystems: resource (R), access (A), usage (U), capacity (C), and environment (E). We calculated the comprehensive security index of water resources and the five subsystems’ scores during 1997-2013 in Chongqing city using weighting function method, and conducted comparative analysis by using the method of factor analysis. Furthermore, we established factors rating model and classified the five subsystems into superior, medium and inferior. Results revealed that the water resources security index of Chongqing increased progressively during 1997-2013, and the coefficients of overall trend was 0.0228/a, indicating that the situation of water resources security improved and the assessment result was consistent with factor analysis. However, the five subsystems had a different variation tendency in time. Among the five subsystems, the scores of access subsystem and capacity subsystem were rising year by year. Compared with earlier years, the scores of resource subsystem and environment subsystem in late years declined. But the score of usage subsystem changed a little. The access factor and capacity factor evolved from inferior to superior while the resource factor and environment factor degraded into the inferior. The efficiency factor degraded into medium from superior. According to the above results, we conclude that the situation of water resources security in Chongqing city has risk possibility in the future. Therefore, the management of water resources should be strengthened and water environment should also be improved, and the water-saving awareness should be intensified.