Fuzzy evaluation model of Yantai water-based system based on index weight reliability analysis

The health status of Yantai urban water-based system(Yantai UWBS) from 1996 to 2005 is evaluated with fuzzy pattern recognition model based on relative membership degree theory. Firstly, with AHP method, the index system is divided into four hierarchies: object hierarchy, criteria hierarchy, factor hierarchy and index hierarchy. And reference to relative national normative criterions or the index standard values of other cities, the index standard values of Yantai UWBS are adjusted synthetically. Secondly, index weights are calculated with comprehensive approach: AHP method is used to calculate the subjective weight; and based on the reliability analysis, CRITIC method is used to calculate the objective weight. Following evaluation results are obtained: (1) The health status can be divided into three stages: healthy evolvement from 1996 to 1997, continuous low level from 1998 to 1999, and stable recovery stage from 2000 to 2005. (2) For the sustainable water resources utilization in Yantai, the key restricting factor is the excessive development of groundwater under the influence of hydrological cycle. (3) The high and low water circle year influences the system status remarkably, and the bad status caused by hydrological cycle has short restore cycle.