面向水质安全预警的流域产业化和城镇化压力源评估方法

为适应水环境风险管理中对压力源的快速评判需求,构建了流域产业化、城镇化压力源评估方法,并开展其应用研究.从压力源危险性及受体易损性着眼,提出了压力源结构风险和布局风险双重控制思路；围绕警示性评估的定位,针对单项及综合风险分析,阐明了评估指标选取、风险指数计算和预警级别划分等步骤,并以三峡库区为案例进行了评估.结果显示,三峡库区产业化、城镇化压力源综合评估Ⅰ级(重警)区主要集中在重庆市主城区附近的8个区县,其结构风险指数值(0.375 6～0.624 6)和布局风险指数值(0.598 7～0.967 8)均较高；Ⅱ级(中警)区域包括江北区、北碚区、巴南区、大渡口区和巫山县,呈现布局风险指数值(0.820 7～1.000 0)较高、结构风险指数值(0.258 4～0.355 5)相对低的特征；Ⅲ级(轻警)区域包括渝东南和渝东北的5个区县和渝中区.其中,渝中区结构风险指数值(0.135 6)小,但因其布局风险指数值(0.960 7)较大而使得综合评估结果为轻警状态. 

Assessment Method of Industrialization and Urbanization Stressors for Water Quality Safety Early Warning

Considering the requirement of fast recognition of stressors for water environmental risk management, an assessment method for the stressors of industrialization and urbanization was established and applied.In view of the pressure of stressors and the vulnerability of receptors, a concept on the integrated control of structure and layout risks of stressors was developed.Oriented by warning evaluation, the detailed assessment steps were clarified for both the single and the comprehensive risk analysis including the index selection, risk index calculation and early-warning level classification. The case study of the Three Gorges Reservoir(TGR) showed that eight counties located near the downtiwn area of Chongqing met grade I level(heavy warning) for the comprehensive risk from industrialization and urbanization. Their stressor structure risk index(0.3756-0.6246) and layout risk index(0.5987-0.9678) were both high. Jiangbei district, Beibei district, Ba′nan district, Dadukou district and Wushan county met grade Ⅱ level(moderate warning), characterized by a higher layout risk index(0.8207-1.0000) and a relative low structure risk index(0.2584-0.3555). Five counties in northeast and southeast of Chongqing and Yuzhong district met grade Ⅲ(slight warning). Yuzhong district had a lower structure risk index value(0.1356), but it was still in the state of slight warning due to its higher layout risk index value(0.9607).