| Water is the most basic material to guarantee the survival of humans and the development of the city.Our country is a typical typical water scarce country,which is one of the poorest countries in the global water resources.But for a long time,the water environment protection consciousness of people is very weak.Water drainage without restraint leads to urban water environment is in a state of a lack of management.With the constant improvement of Chinese urbanization rate,rapid urbanization process will lead to include problems of urban water environment pollution,ecological fragility,water shortages and a series of problems of water environment,the sustainable development of water environment will be severely affected.Urban water environment combined with social factors such as economy and population in this study.The concept of comprehensive quality of urban water environment was put forward,which is not limited to water quality and water resources analysis and evaluation.The comprehensive quality of urban water environment from the perspective of water environment,studying the degree of adaptability,coordination and sustainable development between water environment and social factors such as population,economy,which is a comprehensive reflection of pros and cons of different city functions and degree of adaptability of them.In this paper,on the basis of social cycle of water,the index system of comprehensive quality of urban water environment research was built from water quantity,water use,sewage discharge and water quality four aspects,the index weight was determined using the analytic hierarchy process(ahp),development of urban water environment quality assessment model was established,and urban hierarchies were confirmd according to the evaluation results.Classification method of the research is based on the comprehensive quality score of urban water environment,in view of the existing in the development of urban water environment is the most serious problem of city types,including water resource-poor city,water-overuse city,sewage over-discharge city,low water quality city and good-evaluation city.Some suggestions for improvement have been put forward accordingly in this study.Urban hierarchies were confirmed according to the comprehensive quality of urbanwater environment evaluation results.The result shows that the numbers of excellent city,good city,medium city and poor city is 20,130,84 and 54,respectively,which accounted for 6.94%,45.14%,29.17% and 18.75% of the total cities.Based on the research of the urban classification method,we found that more than two-thirds of the cities at prefecture and above level have problems in comprehensive quality of water environment.There are a quarter of all the cities have more than two kinds of problems.There are many kinds of problems concern wide scope and deep degree,which showing that the overall situation is not optimistic.Water resource-poor city need to strengthen promote water-saving measures and improve the efficiency of urban water;water-overuse city need to vigorously implement the water-saving policy to reduce the use of clean water,increase the use of circulating water,adjust the industrial structure;sewage over-discharge city need to increase the intensity of wastewater recycling,reducing sewage discharge,improve the relevant laws and regulations,enhance the supervision and punishment for sewage discharge;low water quality city need to strengthen the regulation of the outlet of into the river,decrease the quantity of pollutants into the river,improve the water quality of rivers and lakes and other natural runoff.Comprehensive urban must comprehensive measures above,adjust measures to local conditions,establish the corresponding management methods. |
