基于超标风险改进的加拿大水质指数及其应用

将三角模糊数和超标风险度引入加拿大水质指数(CCME-WQI),建立了能够反映超标风险的改进型CCMEWQI。改进后的CCME-WQI通过计算水质指标的超标隶属度与超标风险,可实现对水质不确定性与超标风险的综合考量。在此基础上,评价了重庆市某水库2016—2019年水质状况。结果显示:改进后的CCME-WQI的评价结果较仅反映最差指标类别的单因子评价法的评价结果更为全面、客观。基于超标风险改进的CCME-WQI考虑了即将超标但尚未超标的水质因子存在的风险,在结果显示上比改进前的CCME-WQI更为全面、严格,更适用于评价一段时间内的水体污染程度和超标状态。

Improved Canadian Council of Ministers of the Environment Water Quality Index Based on Risk of Exceeding Standards and Its Application

The triangular fuzzy number and risk of exceeding standards were introduced to the Canadian Council of Ministers of the Environment Water Quality Index (CCME-WQI) to establish the water quality index that can reflect the risk of exceeding standards. In this amended CCME-WQI, membership and excessive risks were calculated to take into account the uncertainty and excessive risks of water quality. And the water quality status of a reservoir in Chongqing from 2016 to 2019 was evaluated by the amended CCME-WQI. It was found that the evaluation results of the amended CCME-WQI was more comprehensive and objective than the single-factor index that only reflecting the "worst index category". Compared to traditional CCME-WQI, the evaluation results were more comprehensive and objective due to the risk of the water quality factors that were about to exceed the standard but not exceeding the standard were taken into account. The results showed that the amended CCME-WQI was a suitable method to evaluate the degree of water pollution and the state of exceeding the standard for a period of time.