Characteristics And Gene Analysis Of Spatial Morphology Types In Historic District Of Chongqing

Urban spatial form is the carrier of culture,and in essence it is a reflection of regional culture.China’s regional culture is rich and diverse,and the urban morphology in the historical period is distinctive.However,under the background of globalization and rapid urbanization,many cities are showing the trend of "homogenization",with similar features and declining features.The formation of urban regional characteristics is a historical process.First of all,it is necessary to "discover" the essential laws of the formation of urban regional characteristics,and then it is possible to select,reconstruct and create them.Therefore,it is urgent for urban construction to study the essential law of the formation and development of regional urban morphological characteristics and explore how to inherit regional traditional culture and shape urban regional characteristics in the contemporary context.Morphological typology studies the organization principles of spatial morphology,focusing on "the invariable content in the process of change",this is similar to the nature of biological genes.As far as typology is concerned,type analysis is not the ultimate goal.Through analysis,induction and summary,exploring viable types and providing reference and guidance for design is the ultimate goal.Therefore,based on the method of morphological type analysis and GIS spatial analysis,taking the historic urban area of Chongqing as an example,this paper studies the type characteristics,generation mechanism and evolution law of urban spatial morphology,extracts the "gene" of urban spatial morphological characteristics,and explores the inspiration for the inheritance and development of urban context and regional characteristics.According to the development process of Chongqing’s historic urban area,the article divides the street network,block and architectural texture into three stages: pre-feudal period(before 1891),post-founding period(1891-1949)and post-founding period(after 1949).It studies the types and characteristics of these spatial morphological elements in each stage,and analyses the law of inheritance and evolution of morphological types and its influencing factors.In the aspect of street network form,this paper analyses the type evolution of street network structure,and combs the inheritance and evolution of different grades of roads;In view of block shape,the change of block scale is discussed from the aspects of block area,length-width ratio and so on;In terms of architectural texture and types,combs the type characteristics,distribution and spatial combination of architectural texture in different periods,as well as the inheritance and evolution of different types of buildings.Finally,it summarizes the interaction between different spatial form elements and the influencing factors of inheritance and evolution.On this basis,the spatial morphological genes of historic urban areas in Chongqing were extracted.The structural morphological genes of "grid type","free reticulation type","regular small scale type","free large scale type" and the architectural texture of "boundary enclosure gene","axis symmetry gene" and "combination sequence gene" were identified.These genes are the carriers of urban genetic information and have the characteristics of "genetic stability",but according to the different geographical environment,they have different manifestations.Based on the type analysis and gene extraction of urban spatial morphological elements,it is proposed to inherit excellent genes,protect dominant genes,continue recessive genes,implant vigorous genes and construct different levels of "morphological genes" network protection system to inherit and develop Chongqing’s historical and regional characteristics.