Construction And Control Of Urban Ecological Security Pattern Based On Supply And Demand Of Ecosystem Service

The rapid development of the city has also brought about environmental damage and increased the risk of urban ecological security.As an important part of China’s land space development strategy,ecological security pattern plays an important role in improving the structure and function of regional ecosystem,protecting biodiversity and maintaining ecosystem services.The ecological security pattern under the guidance of refined governance thinking should pay more attention to the spatial relationship of ecosystem services.It is necessary to accurately identify the spatial location of surplus and deficiency of supply and demand from the perspective of supply and demand matching,improve the matching degree of supply and demand of regional ecosystem services,and realize the coordinated development of regional ecological protection and social economy.Based on the’pattern-process-service’system coupling theory,’patch-corridor-matrix’landscape pattern theory and’supply-flow-demand’ecosystem service flow theory,this thesis systematically expounds the technical route and key methods of urban ecological security pattern construction and control based on ecosystem service supply and demand from four aspects:ecosystem service quantification,landscape structure element identification,structural function system integration and spatial pattern control refinement.Taking Linyi City as an example,this thesis quantifies the supply and demand of ecosystem services by using natural ecological data and socio-economic data,and uses Arc GIS,In VEST,SPSS and other software to quantitatively evaluate the supply and demand of six types of ecosystem services,including water production,food production,carbon sequestration,soil conservation,air purification and leisure and recreation.On this basis,ecological source identification,ecological corridor extraction and ecological node identification are carried out to construct the ecological security pattern of Linyi City,and put forward the control strategy of ecological security pattern elements in Linyi City under the background of land and space planning.The research results can provide ideas for the construction and control of ecological security pattern under the background of territorial spatial planning,and provide reference for further optimization of ecological security pattern in Linyi City.The main conclusions of this thesis include:(1)Based on the pattern process theory,the"patch-corridor-matrix"model is used as the construction method of ecological security pattern,and the"supply-flow-demand"theory is used as the process mapping of the internal function improvement of ecological security pattern,so as to build the theoretical logic of the construction and control of ecological security pattern.From the four aspects of ecosystem service quantification,landscape structure element identification,structural function system integration and spatial pattern control refinement,the technical route and key methods of urban ecological security pattern construction and control based on ecosystem service supply and demand are formed.(2)From the evaluation results of supply and demand of ecosystem services,there is a mismatch between supply and demand in various ecosystem services in Linyi City.The areas with low supply and demand of ecosystem services are concentrated in the built-up areas with dense urban activities.In addition to food production services,the areas with high supply and demand of other ecosystem services are mainly distributed in the northern and western mountains.Due to the wide distribution of cultivated land in Linyi City,the overall grain yield is high,and there is no obvious concentration area in the area with high grain supply and demand.(3)Based on ecological source identification,ecological corridor extraction and ecological node identification,the ecological security pattern of Linyi City was constructed.Among them,the supply source area is 3402.44km~2,and the demand source area is2051.82km~2.A total of 112 corridors were formed,with a total length of 2652km,including 15important corridors and 97 general corridors.Combined with the land use types and resistance values in different widths of the corridors,the width of the important corridors in Linyi City was determined to be 100-200 m,and the width of the general corridors was 30-60 m.The number of integrated ecological pinch points is 161,and the number of integrated obstacle points is 88.(4)Combined with the results of the construction of ecological security pattern in Linyi City and the way of land and space governance,the ecological security pattern control mode of’importance-oriented hierarchical control,functional-oriented classified control,and implementation-oriented demarcation control’was formulated to guide the allocation of natural resources and spatial use control in the whole region,and provide an effective path for the refinement of ecological security pattern control.There are some limitations in the selection of ecosystem service types,the scale connection of ecological security pattern and the refinement of management and control.The next step will focus on the scientific selection of ecosystem service types,the construction of multi-level ecological security pattern,and the clarification of specific management and control requirements.