Quantitative And Comprehensivee Valuation Of The Benefits Of Sponge Cityc On Struction

The construction of a sponge city can purify,store and use rainwater to produce various benefits.The coexistence of qualitative and quantitative benefit indicators causes a lot of ambiguity and uncertainty.The quantitative methods for qualitative indicators are also lacking.Different rainwater facilities The multiple combination methods also further increase the complexity of benefit calculation.Therefore,based on the identification of benefits and the establishment of an indicator system of benefits,a sponge city comprehensive benefit evaluation model was constructed to quantify and analyze the benefits of sponge city construction,and the second batch of sponge pilot cities in Guyuan City,Ningxia as an example for calculation analysis.The paper mainly draws the following conclusions:(1)In terms of benefit identification,this paper considers the function and demand coupling method for identification from both the water resource itself and the urban demand.Then,based on the principles of comprehensiveness,independence and representativeness,and referring to the "Sponge City Construction Performance Evaluation and Assessment Measures(Trial)"(Jianban Chenghan[2015]No.635)document and "Sponge City Construction Technology Guide-Low Impact Development" The contents of the "Rainwater System Construction" document established the sponge city and sponge community benefit index system.The results show that without a unified and recognized system,the reasonable authority of the built system is guaranteed,and the problem of repeated errors and omissions of indicators is avoided.(2)In the quantitative calculation of benefit indicators,refer to the shadow engineering method,alternative cost method,hedonic price method,market value method,willingness to pay method,restoration cost method and protection cost method in environmental economy and water conservancy economics,etc.and improve the method Improve to calculate the benefits of sponge city construction.Afterwards,the comprehensive benefit evaluation model of the sponge city and sponge community was constructed by referring to the "National Sponge City Construction Pilot Performance Evaluation Index Scoring Rules" and using the analytic hierarchy process,coefficient of variation method and weighted coefficient method.The results show that the objective assignment of the selected method prevents the evaluation results from being affected by the evaluator's personal subjective factors,and reduces the burden of evaluation decision-making(3)Taking the second batch of sponge pilot cities in Guyuan,Ningxia as an example,the respective comprehensive benefit evaluation models of the sponge city as a whole and the sponge community were built and analyzed.The second batch of sponge pilot cities in Ningxia Guyuan City were analyzed by example,and the comprehensive benefit evaluation model combining Guyuan characteristics is used to evaluate the sponge city construction benefits.The results show that the comprehensive benefit of Guyuan sponge city construction is 31.418 million yuan per year.The higher water resources,visibility and water environment benefits indicate that sponge city skills can effectively alleviate water shortages and beautify the environmental space,resulting in positive economic and ecological adverse effects.The total benefit of the construction of six sponge communities in Guyuan City is 111.4 thousand yuan/a,of which the economic and environmental benefits are relatively high,which is consistent with the weight analysis results of each community and rainwater facilities.The analysis of the benefits of the rainwater facilities shows that the static and dynamic benefit-to-cost ratios of the sunken green spaces are the largest,and the comprehensive benefits are better.This paper calculates and analyzes the overall construction efficiency of sponge city and sponge community in Guyuan City,Ningxia,a sponge pilot city by constructing a sponge city and sponge community construction benefit model,which provides a reference for the research and construction of sponge city.