基于改进灰靶模型的广州市水生态安全评价

Evaluation of Water Ecological Security in Guangzhou Based on Improved Grey Target Model

为评价广州市的水生态安全情况,引进熵权法的灰靶模型,运用指标加权重的方式对模型中存在的不足进行改善,并以此构建了涉及水健康、水发展及水保障的生态安全指标评价体系,评价了广州市的水生态安全状况。评价结果表明:2011—2015年,广州市的水生态安全综合靶心度值由0. 706 5上升为0. 930 9,安全等级由临界安全等级提升到理想安全等级,说明广州市的水生态朝良性方向发展。但在此过程中,水保障安全仍旧不稳定,其值在临界值周围波动,有向恶性方向发展的风险。经对比发现,由改进后的灰靶模型得到的靶心度值和安全等级的变化趋势都与综合指数法所得结果的变化趋势相同,改进后的灰靶模型解决了原模型在使用度上的不足。这些研究成果可为水生态安全评价实践提供参考。

The grey target model of entropy weight method was introduced to improve the deficiency of the model by adding weight to the index,then,the ecological safety index system of water health,water development and water security was involved,and the water ecological security situation in Guangzhou was evaluated,and the reference basis for the subsequent safety decision and management of aquatic state was provided.The results show that,from2011to2015,the comprehensive target value of water ecological safety in Guangzhou increased from0.7065to0.9309,and the safety grade raised from the critical safety level to the ideal safety level,and it indicated that the water ecological security in Guangzhou city was developing in the good direction.In the progress,the value of water security safety was still unstable,and the value changed around the critical value and had the risk of change in the bad direction.After comparison,it is found that the changing trend of the target value and safety grade on the improved grey target model is the same as that of the comprehensive index method,that proves that the improved gray model solves the shortage of the original model in the use degree,and provides a reference for the practice of water ecological safety evaluation.