Emergy Assessment Of Ecological Economic Effects Of Urban Water System Connectivity Project

As one of the large-scale ecological water conservancy infrastructure in the city,the urban water system connectivity project is an important part of the urban ecosystem.It plays a significant role in protecting the urban ecological environment,ensuring human life and promoting economic development.In recent years,with increasing attention to the construction of urban water ecological civilization,a large number of urban water system connectivity projects have been built in China.It is urgent to quantify and assess the effects of the projects comprehensively and scientifically.Based on the emergy theory and analysis method of ecological economics,this paper mainly studied the composition system and assessment methods of eco-economic effects of urban water system connectivity project.The main work contents and achievements are as follows:(1)Based on the definition and engineering practice of urban water system connectivity project and combined with the idea of system theory,this paper constructed the eco-economic system of urban water system connectivity project,defined the boundary and connotation of the system.Based on the binary water cycle theory,the influence of urban water system connectivity project construction on the binary water cycle process was analyzed,and the interaction between the project and binary water cycle was clarified.The assessment framework of engineering ecoeconomic effect was constructed.(2)Combined with the binary water cycle process under the influence of ecoeconomic system of the urban water system connectivity project,the energy analysis method has been used to analyze the changes of system material flow and energy flow brought by urban water system connectivity project construction from the processes of evaporation,rainfall-runoff,infiltration,water supply,water consumption and drainage regression.The energy system diagram of binary water cycle process was constructed and the formation mechanism of effects of urban water system connectivity project was analyzed.The eco-economic effect composition system of urban water system connectivity project was constructed.(3)Based on the external manifestation of the effect,this paper puts forward the quantitative method of ecological environment,social and economic effects of the urban water system connectivity project by emergy analysis method.Combined with the input-output situation of the engineering eco-economic system,the net emergy yield ratio,environmental load ratio,emergy sustainable indices,engineering net emergy density and engineering water utilization intensity were used to evaluate the engineering eco-economic system.(4)Taking the urban water system connectivity project in Xuchang as an example and using the emergy assessment method of eco-economic effects of the project proposed in this paper,based on the actual situation of regional water body and economic and social development,the eco-economic effects of project in Xuchang were quantified and evaluated in combination with the relevant data of 7 years before and after the completion of the project,and the results were analyzed to demonstrate the feasibility and rationality of this method.