Study On Appropriate Greenway Width Of City Agglomeration In Pearl Delta

The Greenway width (GW) is a critical techno-economic indicator for its planning, construction and management.The GW relates closely to its type and function. The widths of different types of Greenways differ a lot. To a great extent, the GW determines the utilization of the land in a Greenway system. In recent years, the construction of Greenway in China has just started. The design of WG is one of the most controversial issues in the planning and construction practice for Greenway in cities of Pearl Delta. A theoretical deduction of Greenway Width Model to probe into the appropriate width is of both academic values in the study of Chinese characteristic Greenway and operational significance.Based on the studies of literature and planning cases of Greenway and GW, this paper focuses on the discussion of following issues: (1)the function of Greenway and its categorization, (2)the design of Greenway Width Theorectical Model (GWTM),(3)the deduction of the value of the GWTM and (4)the setting of a theoretical width of Greenway widely applicable for city agglomeration in Pearl Delta. The research methods the study adopted are theoretical deduction and cases testing. The former one is to design the Component Value of the GWTM while the latter one is to access the validity of the deduction.This paper has made a systematic analysis and summary of the positive function, negative function and principal function of Greenway. According to its principal function, the types of Greenway of city agglomeration in Pearl Delta are categorized. Based on the study and analysis of theories such as patch-corridor-matrix theory in Landscape Ecology, Landscape Ecological Flow, Edge Effect, Ecological Succession, Phytocoenology, Safe distance theory in Animal Ethology, Animal habitat and action radius, service radius of public green space and Space Model of protected area, which relate to Greenway planning, construction, and management, we deduced the GWTM and its derive models which was built and presented in graphics and figures. According to the principal function and the categorization of the Greenway, the Component Value of the GWTM is calculated. In the light of this model and value, the appropriate width of Greenway of city agglomeration in Pearl Delta is determined.This paper analyzes related studies on Greenway Width at home and abroad, categorizes the greenways of city agglomeration in Pearl Delta according to the function of Greenway, constructs the GWTM and its derive models on the basis of relevant theories and calculates the component value of each type. As a result, the appropriate width of Greenway of city agglomeration in Pearl Delta is determined and suggestions to present main problems in the Greenway construction of city agglomeration in Pearl Delta are made.