Spatial Optimization Of Coal-Based City Based On Ecosystem Service Supply-Demand Relationship

Since the industrial revolution,the urban expansion brought by the rapid economic and social development has had a serious impact on the ecosystem.The demand for ecosystem services has been increasing,but the supply capacity of the ecosystem has been declining due to the erosion of ecological land,and the impact of the imbalance between supply and demand of ecosystem services on residents’ well-being is increasing.Therefore,how to alleviate the contradiction between supply and demand of ecosystem services through land space optimization,so as to achieve sustainable economic and social development,is a difficult problem and challenge faced by many cities and regions.As one of the regions where the contradictions among population,resources and environment are most concentrated,the ecological problems faced by coal resource-based cities are different from other types of cities under the dual effects of coal mining and urbanization,and the ecological system and social system are under great pressure.Therefore,it is not only the need of sustainable development of "ecology-economy-society",but also the need of people’s growing yearning for a better life to optimize the relationship between supply and demand of ecosystems by regulating the spatial structure of coal-based cities.Taking Huainan City,a typical coal resource-based city,as an example,this thesis uses natural,economic and social data,and comprehensively uses In VEST model and supply-demand matrix method to quantitatively measure the supply and demand of grain production services,water production services,carbon sequestration services and leisure and entertainment services in Huainan City in 2010 and 2020 from the town scale.Through the matching degree of supply and demand and Moran index,the temporal and spatial evolution characteristics of supply and demand relationship are analyzed.And using geographical detectors and multi-scale geographically weighted regression to explore the influencing factors and spatial effects of the spatial and temporal evolution of ecosystem service supply and demand;On this basis,the Geo SOS-FLUS model is used to simulate the evolution trend of land use in Huainan City under natural development scenarios and constrained development scenarios,and based on the simulation results,the supply and demand pattern of ecosystem services in different scenarios in the future is predicted,and the optimization strategy of land space in Huainan City is put forward,with a view to providing scientific basis for land space optimization in Huainan City.The main conclusions of this thesis are as follows:(1)The supply of grain production services in Huainan City shows an upward trend,the demand shows a downward trend,and the matching between supply and demand shows a surplus state.The total supply and demand of water production services are on the rise,and the temporal and spatial distribution of supply and demand matching has changed greatly.The supply of carbon sequestration services and leisure and entertainment services showed a downward trend,while the demand showed an upward trend,and the relationship between supply and demand further deteriorated.The matching of supply and demand of integrated ecosystem services is in a surplus state as a whole,but the phenomenon of supply in short supply is increasing in 2010-2020.(2)The high-value areas of food production service SDI(matching degree between supply and demand)in Huainan City are mainly concentrated in the towns in the northwest and southeast,and the low-value areas are mainly distributed in the east and west urban areas.The high-value area of water production service SDI is distributed in the eastern urban area,and the low-value area is distributed in the western urban area and the northwest industrial and mining towns.Carbon sequestration service SDI is concentrated in the central region,and high-value areas are mainly distributed in towns and villages in the northwest corner of Huainan City.Spatial autocorrelation of leisure and entertainment service SDI is low.SDI of integrated ecosystem services,the increase of low-value clusters and the decrease of high-value clusters reflect the worsening trend of the matching degree between supply and demand of integrated ecosystem services in Huainan City.(3)The relationship between supply and demand of ecosystem services in Huainan City is mainly affected by the proportion of construction land,ecological land and cultivated land.Among them,the proportion of construction land has the greatest influence on the matching degree between supply and demand.The calculation results based on MGWR model show that the increase of the proportion of construction land has an inhibitory effect on the improvement of the matching degree of supply and demand of ecosystem services,while the increase of the proportion of ecological land has a positive impact on the matching degree of supply and demand in the global scope,and the influence relationship of the proportion of cultivated land is unstable.(4)The scale expansion of construction land in natural development scenario is faster than that in constrained development scenario,which leads to the erosion of ecological space.The SDI of water production service in natural development scenario is higher than that in constrained development scenario,while the SDI of grain production service,carbon sequestration service and leisure and entertainment service is lower than that in constrained development scenario.On the whole,the relationship between supply and demand of ecosystem services in Huainan City is better than that in natural development scenario.(5)In order to optimize the relationship between supply and demand of ecosystem services,Huainan City should restrain the increment,revitalize the stock,and improve the urban quality by clearing the construction land;Promote the penetration of ecosystem services into urban areas through overall layout and urban-rural linkage;In addition,as a coal resource-based city,Huainan should continue to promote the restoration and management of mining areas,improve the supply of ecosystem services in mining areas,and improve the mining environment.