| As a phenomenon of urban material space,the evolution of urban spatial form is the product of multi-dimensional factors.For different cities,they will have their own unique spatial form and evolution characteristics.Known as the ’ Golden Valley ’,Tongren City is one of the famous historical and cultural cities in China.It is located in Huangnan Tibetan Autonomous Prefecture and has a unique natural landscape and long history.Since the Qin and Han Dynasties,Tongren has a history of more than 2500 years.It has gradually developed from a Qiang settlement to a city with a scale of 12km2.Tongren ’s urban spatial form has shown different characteristics with the continuous development of the city.The research and analysis of Tongren ’s urban spatial form and evolution characteristics can provide key direction guidance and enlightenment for Tongren ’s future urban development.In this paper,the central urban area of Tongren is taken as the research object,and the development history of Tongren city is sorted out.The focus is on the analysis of the urban development of Tongren from the Yuan Dynasty to the present.Before 1949 and after 1949,the qualitative analysis and quantitative analysis of the evolution characteristics of Tongren urban spatial form are carried out.At the same time,the multi-dimensional influencing factors of urban spatial form evolution and their comprehensive mechanism of action are summarized.On this basis,the suggestions for the future development of Tongren urban spatial form are put forward.The main contents and conclusions of this paper are as follows :The first part combs the historical evolution and urban construction process of Tongren before 1949.Taking the Tongren old city established in the Yuan Dynasty as the main object,the development process of Tongren city before 1949 is divided into four periods : origin,temple construction,city construction and county establishment.This paper analyzes the urban spatial form of colleagues in different stages before 1949,including the following aspects,namely,landscape pattern,architecture,external spatial outline,urban spatial expansion,internal spatial structure,land use layout and road network structure.In the second part,based on the evolution of administrative system,social and economic development,urban construction land and urban planning,the development process of Tongren city after 1949 is divided into four stages : initial construction period,adjustment development period,rapid development period and steady development period,and the urban development process and spatial form characteristics of each stage are summarized.This paper combs the data of colleagues and conducts relevant speculation and research,draws the current situation map of colleagues ’ land use in different years,and analyzes the evolution characteristics of colleagues ’ external spatial form and internal spatial structure with the help of Arcgis software.In terms of the evolution characteristics of external spatial morphology,the study found that 1994 was an important turning point in the expansion speed of Tongren City,the expansion speed of Tongren construction land was constantly increasing,the expansion intensity showed a trend of increasing first and then slowing down,and the overall spatial expansion of Tongren City showed a north-south zonal expansion.In terms of the evolution characteristics of internal spatial form,the study found that the development of Tongren ’s urban functions has gradually improved and public service land accounts for a large proportion,and the evolution of Tongren ’s urban spatial form has shown a multi-center development trend.The third part,based on the multi-dimensional influencing factors,analyzes the spatial evolution mechanism of Tongren ’s urban development process,and analyzes the mechanism of urban spatial morphological evolution in different stages before and after1949 and the specific degree of urban spatial morphological characteristics affected by multi-dimensional factors.The analysis found that different factors have different effects on the characteristics of urban spatial morphology.Natural and resource,political and policy,economic,transportation,cultural and other factors can affect the speed of urban spatial expansion of colleagues,and the most influential factors are political and policy and economic factors;natural and resource,economic,transportation and cultural factors can affect the way of urban expansion,and the most influential factors are economic and transportation factors.Nature and resources,politics and policy,economy,transportation and culture can affect the expansion direction of colleagues ’ cities,and the most influential factors are natural and resource,culture and road traffic factors;natural resources,culture,economy and traffic factors affect the internal structure change of Tongren city;cultural,political and policy,economic factors significantly affect the composition of urban land in Tongren.Based on the above analysis,this paper puts forward some suggestions on the development of urban spatial form in the future. |
