Research On The Current Situation And Optimization Of Green Space In The Central Urban Area Of Beijing Under The Guidance Of Ecosystem Services

The contradiction between human and nature is particularly prominent in the central urban area of Beijing which is of glorious historical and cultural traditions with high-density constructions.Green space as the main solution to ecological problems is highly valued,and ecosystem service is widely known as the concept of studying the relationship between human and nature.The expanding research field of landscape architecture provides a new way to solve ecological problems.How to use landscape architecture to solve the ecological problems in the central urban area of Beijing and build a nice living environment has become the focus and difficulty of our research.The research takes the central urban area of Beijing as the subject,constructs the analysis framework of urban green space under the guidance of ecosystem services through the interpretation of urban green space and ecosystem services;summarizes the evolution characteristics of green space through the study of the natural ecological pattern and the development process of green space in Beijing;analyzes the quantitative structure characteristics and gradient differentiation characteristics of the current situation of green space based on the study of landscape pattern,and puts forward the green space problem in central urban area.The study then evaluates and optimizes the current situation of three aspects: the number of elements,the spatial structure and the functional partition from three aspects: the comprehensive benefit of ecosystem services,the evaluation of irreplaceable services and the types of single dominant services,and finally optimizes the green space in the central urban area of Beijing under the guidance of ecosystem services.The main conclusions are as follows:First of all,based on the ontological cognition of green space,the connotation of ecosystem service and the analysis of the relationship between the two things mentioned above,this paper puts forward the idea of urban green space in Beijing city center guided by ecosystem service.Secondly,through the research on landscape pattern,it's found that there are distinct differences among the element quantity structures in different types of green space and shrubland is the main vegetation cover;after analyzing the landscape patterns from different directions in the research zone dynamically by moving window method,it's found that there are obvious gradient analysis features showed inside of,in the northeast of,in the northwest of and in the south of the first green partition,the closer to the edge,the more various the types of green space are and the bigger the amount of green space is,even the more consistent the distribution is.Thirdly,using the concept of ecological green equivalent to analyze the quantitative characteristics of the green space in Beijing city center,the result shows that the whole district,Haidian district,Beijing under the Guidance of Ecosystem Services Shijingshan district meet the requirements,while Chaoyang district,Fengtai district,Dongcheng district and Xicheng district don't meet the requirements;for further step,the research uses linear programming model and combines with a series of city green space limitations to adjust and optimize the element quantity structure of city green space,it seeks for the proper portion of all kinds of green space when the overall benefit is maximum under the preconditions of ecological priority,simultaneously,it offers optimization suggestions for internal improvement and external integration under different circumstances.Fourthly,building the functional connect network with ecological meaning in the research zone based on graph theory and minimum cost model,summarizing structural issue by analyzing current situations,and offering optimization methods like the protection and repairment of important spots,recognition and dredging of important approach,connection and strengthening of current network and integration and classification of current structure from the aspects of spots,approaches,network,structure and so on.Combining with importance calculation and ecological principles,analyzing three important spots types,which are respectively the “dominant spot” with important energy retention function,the “hub spot” in the crucial location of connection and the “transitional spot” connecting many approaches;the three important linkages support the connection among natural elements,among important spots,and among network structure individually;“three steps” network optimization strategy means that carrying out inter-component connection first to improve the network structure entirely,then carrying out intra-component connection to stabilize and strengthen it,in the end,building partial mini network to optimize functions;the tertiary structure suggests that the first level network connects natural elements,the second level network build manually throughout the whole zone and the third level network encrypt the structure.Besides,by analyzing the functional connection network of the whole district,central zone-core zone and core-zone,it's found that different research units have different distance threshold value,which offers basis and proof for deepening grid structure further.Through the research on six administrative divisions,it's found that different development model and different geographical features of cities generate different structural models,including point-like radiating structure,branch connection structure,and reticulated composite structure,which provide directions for network optimization under different modes.In the end,by assessing the importance of ecosystem service in the research zone and analyzing its spatial distribution characteristics,the service characteristics of each district is made clear;within the first green partition,it is the zone mainly leaded by social and cultural service,in the northwest,it is the important ecosystem service zone for comprehensively adjusting and supporting social and cultural service,the northeastern zone and the southern zone are both leaded by adjusting service and supportive service.The main contradict of every district is made clear by then,the function guidance strategy is made to make sure the high efficiency of the leading service from green space.Therefore,this thesis innovates from the perspective,dimension and method.It is concludes that reasonable adjustment of the quantity and structure of factors is an important means to improve the benefits of green space,the construction of functional connection network is an effective way to protect the ecological security and maintain the stability of the system,and the formulation of functional guidance strategy is an important way to ensure the play of leading service universities,which provides the direction for the optimization of green space in the central urban area of Beijing.