Study On Emergy Evaluation Method Of Water Use Efficiency Based On Comprehensive Benefits

The increasingly prominent contradiction between the supply and demand of water resources,and the continuous deterioration of water environment problems,have gradually become the main factors restricting the progress of economic and social development and the improvement of the ecological environment,under the requirements of such systems and policies as "Three Red Lines","Sixteen-character Water Control Policy","Accelerating the construction of water conservancy projects and strengthen the supervision of water conservancy industry",how to expand the concept of water use efficiency and scientifically evaluate the water use efficiency of the agricultural,industrial,domestic and ecological sectors has become a key issue facing the practice of water resources management.This article relies on the National Natural Science Foundation Youth Fund project "Study of emergy evaluation method of water use efficiency based on energy analysis of water process"(No.5160090427),in view of the current situation that the evaluation of water use efficiency in different departments does not fully consider the impact of water use on the economy,society and ecology,and the evaluation indicators of different departments are inconsistent,according to the emergy theory and analysis method,the research on the emergy evaluation method of water use efficiency based on comprehensive benefits is carried out.The main work and results are as follows:(1)Based on the eco-economic system of water resources utilization,and according to the definition of efficiency,expand the concept of water use efficiency,considering the full impact of agriculture,industry,life,and ecological water use on the economy,society,and ecological environment,a new concept and evaluation framework for water use efficiency based on comprehensive benefits is proposed.(2)According to the interaction and conversion relationship between water resources and other substances and energy in the agricultural,industrial,life and ecological sectors,guided by emergy theory and analytical methods,construct water energy efficiency energy system maps of different departments,determine the composition of water use efficiency of different water departments and the quantitative method of energy efficiency,an evaluation method of agricultural,industrial,life,ecological and regional water use efficiency emergy based on comprehensive benefits is proposed.(3)Taking Zhengzhou as an example,using the emergy evaluation method of agricultural,industrial,life,ecological and regional water use efficiency based on comprehensive benefits,the water use efficiency of agriculture,industry,life,ecology and region in Zhengzhou from 2011 to 2017 was evaluated,and the evaluation results were discussed and analyzed.