Research On Urban Water-Energy-Food System Coordination Based On Policy Regulation

Water,energy and food are the basic resources necessary for people’s survival and development.With the development of society,population growth and acceleration of urbanization,the global demand for resources has increased rapidly.At the same time,the global climate change,resource crisis and other factors have seriously threatened the sustainable development of the three kinds of resources.To meet the growing demand of resources,which has become a major challenge for around of the world.Due to the importance of the three types of resources,researchs on the sustainable development of the three types of resources has been prosperous.However,because water,energy,and food are widely associated in the production and consumption process,especially in urban areas,population and resources are highly concentrated in urban space,and the metabolic pathways of various resources in the urban system overlap and overlap,making the correlation effect obviously.The study of a single resource is difficult to reflect the overall appearance of urban resource metabolism.Therefore,to carry out a comprehensive analysis of three types of resources at the city level and consider the impact of these "associations" on various subsystems in the process of resource management is of great significane for clarifying the metabolic characteristics of three types of resources and realizing sustainable development of resources.First,this research analyzes and identifies water,energy,and food metabolic pathways based on the Material Flow/Energy Flow Analysis,establishes a quantitative analysis network model for water,energy and food metabolism on city level.Second,the model is applied to quantitatively analyze the metabolic characteristics of water,energy and food and identify the associated nodes and metabolic pathways among the three metabolic networks in the social and economic system of Guangzhou from 2013 to 2017,in which food is represented by two elements of nitrogen and phosphorus.Third,according to these associated nodes and metabolic pathways,a comprehensive water-energy-food metabolism network in Guangzhou is constructed.And then an comprehensive evaluation index system is established to evaluate the development of the water-energy-food integrated network in Guangzhou.Lastly,based on the integrated water-energy-food network and system dynamics theory,a system dynamics model was established to examine the evolutionary trend of resource metabolism in Guangzhou under different policy scenarios from 2013 to 2030.The research results show that from the quantitative analysis of water energy and food metabolism in Guangzhou,it can be seen that Guangzhou’s resource demand is large and the recycling rate is low.During 2013-2017,the total water input decreased from 68.4×108m3 to 65.3×108m3;the amount of energy input increased from 53.8×106 tce to 62.3 million tce,the amount of N input increased from 73081.0 tons to 105520.3 tons,and the amount of P input increased from 10943.5 tons to 15152.3 tons.Through the identifying and analyzing of Guangzhou’s water,energy and food metabolism network,it is found that the directly related associated nodes among the three networks are thermal power generation,petroleum processing and refining,water production and supply,wastewater treatment,agricultural cultivation,animal husbandry and food processing nodes.Based on these nodes,an integrated waterenergy-food network is established.Based on the analysis of the established integrated network,it is known that in 2017,the total water consumption related to food production in Guangzhou is 12.19 × 108m3,and the energy-related water consumption is 22.91 × 108m3 The energy consumption related to food production is 113,600 tons of standard coal,and the energy consumption related to water is 21,700 tons of standard coalAccording to the comprehensive evaluation of the established water-energy-food integrated network in Guangzhou,it can be seen that the demand of resource consumption in Guangzhou has gradually increased,the level of self-sufficiency of resources has gradually decreased,and the impact on the environment has also shown a strengthening trend.According to the result of system dynamics simulation,it can be seen that the total water demand can be significantly reduced by increasing the utilization ratio of recycled water.Increasing the recycling rate of waste resources can reduce the impact on the environment,but it will increase energy consumption to a certain extent.By rationally formulating power regulation policies,energy demand can be reduced,and it will also have an impact on water demand.In summary,from the perspective of the synergy between water,energy and food,comprehensive consideration of the impact of resource management policies on various resource systems can better achieve the sustainable development of each kind of resource.