Study On Emergy Analysis And Coupling Coordination Of The Benefits Of Sand Prevention And Control Project

Desertification is a global ecological and environmental problem.China has been promoting the work of desertification prevention and control since the 1980 s.Sand prevention and control project is an important measure to protect nature,improve people’s livelihood,and promote economic development in sand areas.It has become one of the most important ecological environment construction projects in China.However,what are the benefits of the implementation of sand prevention and control project so far? How to reasonably monitor and evaluate the benefits of sand prevention and control project plays a vital role in the sustainable promotion of desertification.Yulin City is located in the southern edge of Mu Us Sandy Land which is one of the four major sandy lands in China,it is one of the regions with the most serious desertification in China,and it is an area with remarkable desertification control effect in China.Therefore,based on the survey data of national key R&D projects,taking Yulin City as an example,the method of emergy vavlue analysis is mainly used.The paper studies the benefits of sand prevention and control project by combining qualitative and quantitative analysis,normative research and empirical research,relying on the emergy theory,and combining the theories and methods of ecological economics and systematics.The core content of the paper is divided into four parts:(1)Dynamic evolution analysis of the impact of desertification prevention and control project on ecological economy;(2)From the perspective of emergy,the benefit analysis of sand prevention and control project.It mainly includes the analysis of ecological and economic benefits,the analysis of sustainable utilization of water resources and the analysis of ecotourism benefits;(3)Measurement and analysis of comprehensive emergy benefits of sand prevention and control project based on emergy index system;(4)Coupling and coordination analysis of comprehensive benefits of sand prevention and control project.The main conclusions of this paper are:(1)After the implementation of sand prevention and control project,the ecological environment has improved,the regional desertification has decreased,and the control rate of desertification land has reached 93.24%.The total value of vegetation ecological services has increased.Among the individual service values,raw materials,providing aesthetic landscape,gas regulation,and water conservation values have increased significantly.Land use has improved,agricultural comprehensive productivity has increased,and the overall ecological environment has gradually developed towards a virtuous circle.(2)From the perspective of emergy,after the implementation of the policy of desertification prevention and control,the total emergy input and output of the ecological economic system of Yulin City showed a steady growth trend,the ratio of emergy input to output showed a downward trend,and the efficiency of resource utilization was improved.The emergy yeild ratio(EYR)shows an increasing trend and the level of economic development is improved;However,the population carrying capacity is insufficient,the environmental load ratio increases,and the environmental pressure is still great;From the perspective of sustainable development,the ecological economy of Yulin City has gradually evolved from a backward state to a developing state,the pressure on the ecological environment has gradually increased,and the support ability of system resources for economic development has been declining.(3)After the implementation of the policy of sand prevention and control,the emergy ecological footprint of water resources in Yulin City shows a fluctuating upward trend,and the emergy ecological carrying capacity of water resources is insufficient.Yulin’s water resources are in the state of ecological deficit and sub-security;However,the ecological environment has improved and the tourism industry is in a state of wealth inflow,which is sustainable.However,with the improvement of the ecological environment,the emergy input and output of the tourism show an increasing trend,the exchange ratio of tourism emergy increases,and the tourism industry is in a state of wealth inflow,which is sustainable.At the same time,with the increase of tourism environmental load raio,the pressure of tourism on the environment is still increasing.(4)By using the grey correlation analysis and Topsis entropy weight method,it is concluded that the comprehensive benefits of sand prevention and control in Yulin City from 1996 to 2020 were transferred from poor level to good level,with remarkable results.The degree of coupling and coordination between systems transits from a seriously misadjusted state to near misadjusted state,and the functions of various elements gradually develop to a good state.Based on these conclusions,it is proposed that Yulin City can further promote the desertification prevention and control projects by improving the financial security system,regional resource protection and environmental governance,intensive and economical use of water resources,and expansion of desert ecotourism to promote the coordinated development of the eco-economic system.Some contents of this study make some innovations in the analysis methods and concepts of emergy theory,especially the concept of emergy EGDP and the proposal of regional emergy density analysis method,which are innovations in the analysis methods of emergy theory.In addition,with the development and application of artificial intelligence and big data,some research contents also need to be improved and deepened.