Research On The Spatio-temporal Evolution Of The Supply And Demand Pattern Of Ecosystem Services In Dandong

Ecosystem services are the resource and environmental foundation for the survival and development of human society.Affected by the regional differences in natural conditions and human activity intensity,ecosystem services supply capacity and demand levels show significant spatial heterogeneity.The intensity of human utilization of ecosystems has gradually increased in the process of economic development.Ecosystems are faced with a series of problems such as service function degradation and habitat deterioration.However,human beings are increasingly pursuing high-quality ecological services,making the contradiction between supply and demand of ecosystem services more and more obviously.Measuring the temporal and spatial evolution of ecosystem service supply and demand,and evaluating the matching relationship between supply and demand,has strong theoretical guidance and practical value for coordinating ecological and economic development and exploring sustainable management of regional ecosystems.This thesis takes Dandong as the research area,based on InVEST ecological model simulation and Arc GIS geospatial analysis method,quantitatively evaluated the temporal and spatial distribution pattern and change characteristics of water production,soil conservation,carbon sequestration,and habitat quality services in Dandong in 2000,2010,and 2020.Combined with the supply and demand ratio index,the Z-score standardized spatial statistical analysis method,this thesis measures the various of the supply-demand matching relationship of ecosystem services and comprehensive ecosystem services,and the differences between administrative districts in Dandong,in order to provide reference suggestions for the future ecological resource management and spatial development planning of Dandong.The main conclusions are as follows:（1）From 2000 to 2020,the land use types in Dandong were mainly forest land and cultivated land.During the study period,various land use patterns changed significantly.In the first 10 years,the area of forest land and grassland decreased the fastest,and the area of cultivated land and artificial land increased rapidly.In the next 10 years,with the promotion of returning farmland to forests and urbanization,the area of cultivated land decreased,while the forest land and artificial land increased.The northern administrative region has a large proportion of ecological sources,and the southern administrative region has a large proportion of cultivated land and artificial land,and the growth rate is fast.In some areas,ecological governance has achieved remarkable results in recent years,but human interference on the ecological environment has been continuously strengthened in the process of urbanization.（2）From 2000 to 2010,the supply of carbon sequestration services and habitat quality services in Dandong decreased to varying degrees,and rebounded from 2010 to 2020 with the improvement of natural conditions.The supply of water production service and soil conservation service first increases and then decreases with the fluctuation of climate.The spatial distribution of various ecosystem services generally presents a distribution pattern of high in the north and low in the south,and high in the east and low in the west.The ecological environment in the northeastern region is relatively good,and the supply of various ecosystem services in Kuandian is significantly higher than that in other administrative regions.The low-value areas are mainly in the Zhenxing,Yuanbao and the coastal areas of Donggang,which are greatly affected by human activities and have poor ecological environment.（3）From 2000 to 2020,the demand for carbon sequestration services and habitat quality services in Dandong continued to increase,and the demand for water production services and soil conservation services showed a trend of first increasing and then decreasing.The demand for water production services shows a spatial distribution pattern of high in the south and low in the north.The demand for soil conservation services gradually increased from southeast to northwest and northeast.The demand pattern of carbon sequestration services basically shows a decreasing trend from southeast to west.The demand for habitat quality services is higher in areas with high density of population and natural ecological environment.There are significant differences in demand between administrative regions.Donggang,Zhenxing,and Yuanbao with higher urbanization levels have significantly higher demand for water production services,carbon sequestration services,and habitat quality services than other administrative regions.The demand for soil conservation services in Kuandian and Fengcheng is higher than that in other regions.（4）The average supply-demand ratio index of water production service,soil conservation service,carbon sequestration service and habitat quality service in Dandong is greater than 0,and the total supply of each service can basically meet the needs of the study area.Due to the large differences in natural conditions and socioeconomic conditions between regions,the spatial and temporal heterogeneity of supply and demand matching of various ecosystem services is obvious.The supply-demand ratio of water production services and soil conservation services is spatially low in the southwest and high in the northeast.The supply-demand ratio of carbon sequestration services and habitat quality services is greater than 0 in most areas,and the low-value areas are mainly distributed in the southeast along the river.There are four different types of supply and demand matching for water production services in Dandong.Soil conservation services are mainly based on the spatial matching types of high supply and high demand,and low supply and low demand.Carbon sequestration services and habitat quality services are dominated by a deficit model with low supply and high demand and a surplus model with high supply and low demand.（5）The ecosystem services of Dandong can meet the needs of the city’s ecosystem services.The surplus areas of ecosystem services are mainly concentrated in the northern region,and the south and southeastern regions along the river are currently in serious deficit.The surplus of integrated ecosystem services is decreasing year by year,and it is developing in the direction of the evolution of the imbalance between supply and demand.In the future,the development of Dandong can rely on the good ecosystems of Fengcheng and Kuandian,and take measures to improve the ecological environment according to the different natural conditions of the surplus area and the deficit area.Strengthen the construction of ecological function zones in key areas,consolidate the ecological foundation for green development,improve the supply capacity of ecosystem services,reduce service consumption,and improve the imbalance between supply and demand to improve the utilization efficiency of natural resources.Strengthen the planning and management of Dandong’s territorial space to promote the coordinated development of Dandong’s economy and ecosystem.