Research On The Spatial Characteristics Of The Cultural Lineage And Its Evolutionary Mechanism In The Historical City Of Lhasa

Lhasa,meaning "holy land" in Tibetan,is located in the hinterland of south-central Tibetan region of China,on the north bank of Lhasa River,a tributary of Yarlung Tsangpo River,with an average altitude of 3,650 meters.In the 7th century A.D.,Songtsen Gampo unified the whole Tibet and moved the capital to Lhasa to establish the Tubo dynasty,which opened the history of the city of Lhasa for more than 1300 years.As one of the first national historical and cultural cities,Lhasa is one of the most typical cities built by Tibetan people,and its urban space reflects the regional characteristics and ethnic features of Tibet.With the promotion of the national aid program for Tibet,the modernization of Lhasa city is accelerating,and in this context,the characteristic style and culture of Lhasa city are facing serious challenges.In order to protect the city style,continue the culture of the city,realize the protective re-living and sustainable development of Lhasa historical and cultural city,so the study is conducted for the city culture of Lhasa.This paper takes Lhasa’s historic urban area as the research object,draws on the theories of urban cultural lineage,historical geography,urban morphology,cultural ecology and other related theories,introduces the perspective of cultural lineage space on the basis of urban spatial morphology research,and conducts a "common time" and"ephemeral" analysis of Lhasa’s historic urban area."At the same time,the spatial elements of the historic district are identified,the spatial characteristics of the historic district are summarized,the factors influencing the spatial evolution of the historic district are summarized and the mechanism of the spatial evolution of the historic district is summarized,and finally,the spatial value of the historic district of Lhasa is evaluated and targeted strategies for the protection of the urban cultural heritage are proposed.The main content of the article contains the following three parts.Combing the spatial pattern evolution of Lhasa’s historic urban area.It analyzes the historical and geographical basis of Lhasa’s urban development,clarifies the historical process of urban formation and development,and divides the spatial development process of Lhasa into four stages based on the background of social development,the political and religious status of the city,the period of historical relics,and urban construction: the development stage of the capital city as the center of power(633-842),the development stage of the sacred city as the center of religion(842-1642),and the development stage of the holy city as the center of politics and religion(1642-1960),and the development stage as the capital of Tibet after peaceful liberation(1960-present).The spatial pattern of the historical urban area is analyzed according to the stages,the spatial characteristics of each stage are summarized,and the changes are compared vertically to summarize the spatial evolution.Analyze the mechanism of spatial evolution of the cultural lineage in the historic city of Lhasa.On the basis of the evolution of spatial pattern,we extract the explicit and implicit elements of each development stage,classify the explicit elements into structural and functional elements,and analyze the implicit elements in relation to each stage of cultural space.The characteristics of the cultural space are summarized according to the characteristics of the constituent elements of each stage of the cultural space,and the mechanism of the evolution of the cultural space in the historical city is explored,which shows that the special environment of the plateau supports the formation of the cultural space,the socio-economic factors drive the development of the cultural space,and the change of the political system and the development of religious culture are the main driving force of the evolution of the cultural space.Based on the study of the characteristics of the cultural space and its evolution mechanism,we establish a system for evaluating the value of the cultural space in Lhasa’s historic city,evaluate the value of the cultural space by using expert assignment and hierarchical analysis,and propose targeted strategies for protecting the cultural space in Lhasa’s historic city based on the results of the value evaluation,which are to protect the function and structural characteristics of the cultural space itself,to protect the cultural and emotional elements associated with the cultural space,and to protect the cultural space.Based on the results of the evaluation,we propose targeted strategies for the conservation of cultural heritage spaces in Lhasa’s historic district,including the preservation of the functions and structural characteristics of cultural heritage spaces,the preservation of cultural and emotional elements associated with cultural heritage spaces,and the preservation of the translation process and utilization of cultural heritage spaces.Based on the above research content,we hope to provide a useful reference for the future protection and utilization of the cultural space in Lhasa’s historic district and the construction and development of Lhasa’s historic and cultural city.