Research On The Relationship Between City Scale And Industrial Structure

Industrialization and urbanization have been the most important features of modern economic growth,and high levels of industry and urbanization are the continuous driving forces for world economic growth process since the 18 th century.Over the past seven decades,urban agglomeration has become the basic direction and main form of global urbanization.The major difference from the development of a single city to a metropolitan is that the space allocation of the industry is no longer based on the efficiency of a single city,but maximizing the efficiency of the combination of urban agglomerations.There are three contents.Firstly,the difference in the distribution of industri al functions in different levels of cities.Secondly,the industrial scale is based on the size of the economic population of the urban agglomeration instead of a single city.Thirdly,the urban agglomeration promotes the specialization of individual urban functions and the integration of urban agglomerations.The vibrant and large cities cluster not only owns a large number of population but also gathers huge economic activities in various functional forms.It includes not only large-scale international trade manufacturing and production,but densely-populated area of university scientific research institutions,science and technology and industrial innovation.The urban area has a multi-core character and is represented by a symbolized core city.The dynamic large cities group is the spatial support of the national economy and the display of international competitiveness.It is also the key to the continuous improvement of national economic efficiency.As a spatial expansion of urbanization,urban aggl omerations are continuous urban areas.They are also the orderly structure of large,medium and small cities.They are further referred to as the interdependence of the diversified division of labor among cities and the industries that are compatible with the scale structure.Structure distribution.The focus of this paper is to clarify the urban structure within the urban agglomeration on the basis of fully drawing on existing research achievements.Under the framework of the agglomeration of spatial econo mic theory and increasing returns to scale,based on theoretical analysis and empirical tests,it is suggested that cities of different scales and grades within urban agglomerations have different industrial structures.This is the interdependence of cities and the continuation of urban agglomerations.The internal basis for expansion is also the key to maximizing the spatial efficiency of urban economy.In the past century,the trend of world's major urban agglomerations development led by the United States has resulted in the formation of a huge number of large urban agglomerations that have extensive world influence and have greatly improved the competitiveness of the United States.U.S.urban agglomerations,as the research object,focus on the relations hip between the city scale and industrial structure in order to provide important theoretical and practical significance for the development of urban agglomerations in China.The logical structure of this paper is based on the theory of spatial economics a nd under the framework of agglomeration and increasing returns to scale propose a new hypothesis that urban agglomerations are born within the urban scale structure.Then the relationship between urban agglomeration industrial structure and the size of cities is developed.Specifically,it adopts statistical analysis and empirical analysis method and conducts the following research results: first ly,the distribution of the scale of the United States' advanced industries.According to the highly innovative advanced industries of the United States,there are significant gathered in large cities.It is verified that in the era of scientific and technological revolutions,especially experienced digital breakthroughs,large cities have rapidly shifted from manufa cturing centers to innovation centers,and due to the accumulation of innovative agglomeration effects,major cities have advanced Industries especially those represented by the digital economy that have increasingly enhanced their ability to gather servic es and become core functions of large cities.The second one is based on the hypothesis of spatial scale effect,which verifies the intrinsic link between the scale of the city and the industrial structure.It is verified without loss of generality that di fferent cities will have differences in the industrial structure.This difference is reinforced by the difference in land rental costs and spatial distances,as well as the different levels of economic development.The specific empirical test concludes thr ee following conclusions: firstly,cities obey a certain size structure distribution,that is,distribution of large,medium and small.The trade-off relationship between returns to scale and transport costs has led to changes in the industrial structure that have affected the size of the city.Secondly,among large,medium,and small cities there are intrinsic interdependencies.Interdependence results from agglomeration and industrial differences.Large,medium and small cities each play different roles.Finally,the size of cities,innovation processes,and scarcity of land determine the differences in industrial structure between cities.