Research On The Streetscape Design Strategies On Landscape Gene Perspective

In the context of city development transferred from incremental era into stock era,streetscape is becoming the New Blue Ocean for designer,as a showcase of city image and a significant platform which convey the quality of cityscape.However,in the process of streetscape construction,some problems are commonly existed,such as city characteristics elimination,and streetscape elements convergence.Moreover,the existing researches are focus on the regional characteristics of the specific city,the research conclusions are not of universality.Based on the above background,the researcher takes“Basic Theory and Model–Theoretical Deduction–Practice”as the linage to build the streetscape design and evaluation method,from the perspective of landscape gene.The conclusions are of positive significance to the streetscape quality improvement,and are the solid enrichment of Road Landscape Design Theory.First,the researcher defines the streetscape and its appearance.According to the composition elements of street space,the researcher summarizes the general method of streetscape design based on regional cultural characteristics.In accordance with the theory of Molecular Genetics and Landscape Genetics,the researcher then discriminates the similar organism characteristics of streetscape,which includes the heritability,dynamic stability and variability,laying a solid theoretical basis for the subsequent research.Secondly,the researcher proposes the basic concept and model of streetscape gene by analogizing with biological DNA model,with explaining the extract principles,extract methods and classification principles（by feature and by attribute）of streetscape gene.Subsequently,the basic properties,that are Uniqueness,Prominence,Additivity,and the intrinsic meaning from cultural,psychological and aesthetic aspects of the streetscape gene are summarized.Moreover,the researcher presents the expression and variation mechanism of streetscape gene by comparing with the biological gene.Thirdly,the Object-Oriented Classification Pattern of Streetscape Gene（OOCPSG）is used to extract the Streetscape Information Unit（SIU）and its Recognition Factors（RF）.The theoretical framework of streetscape gene is further summarized by the"Streetscape Information Unit（SIU）–Streetscape Information Point（SIP）–Streetscape Information Chain（SIC）"model.The researcher subsequently analyses the SIU and classifies them by attribute,with explaining its transmission path.The identification process of the SIC is summarized to demonstrate the spatial distribution pattern of street space.The general formula of streetscape construction=!∪_"∪_#∪_$is introduced to guide the planning,design and renewal work of urban road landscape.The streetscape gene expression rate E and the classification model are introduced to evaluate the style of SIC.Then,the research of spatial feature of SIC is carried out,and the calculation method of streetscape image semantic segmentation is constructed based on the PSPNet model of Res Net50.The objective evaluation indexes such as I₇（Greenness）,I₈（Enclosure）,and I₉（Openness）,are calculated by obtaining the pixel ratio of landscape element in the image.Subsequently,based on the above analysis of the style and spatial of the SIC,the streetscape quality evaluation method is proposed to comprehensively appraise the service level,environmental attributes,cultural characteristics and spatial quality of street.Finally,taking Huanan Road and Ninghai Road in Nanjing as the research objects,the streetscape design method from the perspective of streetscape gene is applied to extract the streetscape gene of Nanjing roads and analyze the style and spatial of the SIC.Eventually,The quantitative evaluation results are A_IIIC_III（22.764）for Hunan Road and A_IIC_II（23.831）for Ninghai Road.According to the evaluation results,targeted landscape renewal strategies and design guidelines are proposed to achieve the overall improvement of streetscape quality.In summary,the researcher integrates the multidisciplinary theory of landscape gene,human geography and machine learning into the streetscape design process,and forms the streetscape planning model based on landscape gene.The streetscape gene strategies can highlight urban characteristics,convey cultural values,enhance regional cognition and maintain the living heritage of the streetscape,which has theoretical innovation and practical application value.In addition,the construction of the streetscape quality evaluation provides the expansion of the evaluation method for the engineering practice,so that the streetscape quality evaluation conclusion has a deeper and diversified connotation.