Study On Comprehensive Evaluation And Coupling Coordinated Development Of Water-Energy-Food System Security In North China

Because water,energy and food resources are interrelated,influenced and restricted each other,the study of water,energy and food as a system problem provides a new way to solve the problem of water,energy and food.As a complex system,the security of its comprehensive evaluation index and coupling coordination degree is of great significance to ensure the healthy and sustainable development of regional waterenergy-food system.Based on the domestic and foreign research,this paper establishes the basic framework of water-energy-food system,establishes the evaluation index system according to the characteristics of regional development,uses the comprehensive evaluation index,coupling degree and coupling coordination degree model to evaluate the security and coupling coordination of water-energy-food system in North China,and then combined with the grey correlation analysis method to determine the main influence factors of coupling coordination degree Finally,BP neural network is used to predict the coupling coordination level of North China from 2020 to2030.The main achievements are as follows(1)This paper analyzes the temporal and spatial distribution of water resources,energy and food resources in North China from 2003 to 2019.The development analysis of water resources includes the spatial and temporal distribution of rainfall,groundwater resources,per capita water resources and water use structure;the development analysis of energy includes the production and consumption of energy and the structure of energy consumption;the development analysis of food includes food the change of grain yield and the structure of grain yield.(2)The comprehensive evaluation index of water-energy-food system in North China from 2003 to 2019 shows an overall upward trend,but the regional development is unbalanced.The comprehensive evaluation index of Beijing Tianjin Hebei region in2019 is 0.524,0.549 and 0.622 respectively.The comprehensive evaluation index of Shanxi Province and Inner Mongolia in 2019 is 0.584 and 0.593 respectively.The comprehensive evaluation index of Beijing and Tianjin is lower than that of Shanxi and Inner Mongolia is greatly affected by the comprehensive evaluation index of water resources.(3)The overall development of coupling degree and coupling coordination degree of water-energy-food system in North China is good,and the coupling degree is between 0.989 and 0.999,which is in a high level coupling stage as a whole,and the provincial administrative regions are also in a high level coupling stage;from 2003 to2019,the coupling coordination degree shows a fluctuating growth,and the coupling coordination degree increases from 0.621 to 0.757,which is fluctuating in Hebei Province In 2019,the coupling coordination degree of water-energy-food system in North China Hebei Province > Inner Mongolia > Shanxi Province > Tianjin City >Beijing city are in the intermediate development stage of basic coordination level.(4)The main influencing factors of coupling coordination degree of water-energy-food system in North China are analyzed by using grey correlation analysis.The results show that water resource is the core factor affecting coupling coordination degree of water-energy-food system in North China,followed by energy and food production and consumption.Improving the resistance to risk ability of water resources in North China,ensuring the security of water resources,promoting the production of energy and food,and reducing the waste of resources play a key role in the safe,healthy and sustainable development of water-energy-food system in North China.(5)BP neural network is used to predict the coupling coordination degree of waterenergy-food system in North China.The overall coupling coordination degree of North China will keep fluctuating and rising from 2020 to 2030.The prediction results show that the coupling coordination degree of water-energy-food system will increase to0.797 by 2030.