基于AHP-熵权法的兰州市水环境安全模糊综合评价

水环境安全是区域经济和社会发展的关键因素,为了有效评价城市水环境安全状况,立足于兰州市水环境和水资源现状,依据压力-状态-响应(PSR)模型理论,筛选了5个评价子集共28项评价指标构建了兰州市水环境安全评价指标体系,采用了层次分析法和熵权法计算指标的组合权重,选用模糊综合评价法对兰州市2010-2017年水环境安全状况进行评价。结果表明,2010-2017年兰州市水环境安全综合评价值均处在III级,总体呈明显下降趋势,表明兰州市水环境安全状况逐步改善。其中,2011年综合评价值最高,2017年最低,临界II级。依据评价结果和实际情况,找出了影响兰州市水环境安全的7项控制指标,在不同控制指标的基础上,为水环境保护提出了相应改善措施和建议。

Fuzzy comprehensive evaluation of water environment safety of Lanzhou based on AHP-entropy weight method

The given paper is to engage itself in an investigative study on the water environment safety of Lanzhou in 2010-2017 from the point of view of the regional economic and social development,partivularly for Lanzhou City,Gansu.For the sake of better evaluation,this paper has established a water environment safety evaluation index system.According to the social and economic background,water environment and water resources status of Lanzhou,a total of 28 evaluation indices in 5 evaluation subsets that we have chosen through the pressure-state-response(PSR)model.The given study has successively been followed by an analytic hierarchical process(AHP)and entropy weight method to determine the comprehensive weights,the triangular membership function to calculate the membership degrees of the indices,whereas the comprehensive evaluation has been done in the principle of the weighted average by using the multi-level fuzzy comprehensive evaluation method.And,then,the water environment safety evaluation index system and the index grading system have been built up based on the above 2 national criteria.The water environment safety system of Lanzhou in 2010-2017 has been put into work just based on such water environment safety evaluation indexes.The results of the actual execution have indeed give a push in its water environment overall improvement to the safe level(level III)from 2010 to 2017,in the investigation period.Speaking more specifically,the comprehensive evaluation value in 2011 was close to unsafety(IV level),but in 2017 the water environment safety turned to be close to safety(II level).In addition,the evaluation results and the actual situation reveal that the method for evaluation can be said reasonable and effective in asserting the urban water environment safety through 7 indices,including the GDP per capita,the water consumption status quo per 10000 Yuan,the annual urban water supply sum-total,the sewage emission efficiency,the recovery ratio of the sewage treatment,the density of drainage pipeline network in the living-quarters sphere,and the environmental protection investment share of GDP,correspondingly and respectively,all of which should have a significant impact on the water environment safety of the city.And,in the final analysis,the corresponding improvement measures and suggestions have indeed been brought about for the future water environment protection reininforcement in response to the needs of different control goal categories.