The Research On The Time-Scale Effect Of The City-Size Hierarchy In China

After nearly 60 years construction and development, since the birth of New China, the cities of China have changed a lot in quantity and size. Is the cities' development equilibrium, among cities of three different sizes? Is the current City-Size hierarchy of China reasonable? And what else problem exist in the city development of China? According to this, the present paper summarizes the studies on City-Size hierarchy system in China, and introduces the theories of "Rank-Clock", "Distance Clock", and "Half Life". This paper researches the present characteristics of the City-Size hierarchy system of China. This paper uses the non-rural population datas of cities at prefecture level or above in China after the foundation to analyze the evolutions of scale structure of these cities and the evolutions of Rank-Size distribution. This paper describes and analyzes the "Rank-Clock", "Distance Clock", and "Half Life" of these cities. This paper uses the historical demographic data to describe and analyze the "Rank-Clock" of 30 historical cities in China from the year dot to 2000 A.D. This paper analyzes the weakness of resource-based cities in northeast china, rising and development of the coastal cities in east china, the study of the economic integration in yangtze delta and the study of western development.The main research results:①research results of the evolution of urban scale structure and City-Size distribution show that numbers of big, medium-sized and small cities are unbalanced with total population and total economic scale; the general trend of City-Size distribution is increasingly balanced; after 1980s, the numbers of cities at prefecture level or above increased rapidly, big cities haved 640 thousand and above to megalopolis haved 2.56 million are increasing with the quickest speed.②The result of "Rank-Clock" shows that megalopolis' "Rank-Clocks" change less and their ranks lie in the front of the country, such as Shanghai, Beijing, Chongqing, Wuhan, and so on. The "Rank-Clocks" of cities in the northeast area change more and their ranks gradually decrease; The "Rank-Clocks" of cities in the east and coastal areas of China change more, too. And their ranks increase rapidly. The "Rank-Clocks" of some cities in the west and inner land don't change. Because that their ranks are more than 100, all the time.③The result of "Distance Clock" shows that high grade cities change less,and low grade cities and new cities change more; The whole urban system changes slowly, only changes a little big between 1980 and 1985, and between 2000 and 2005.④The result of "Half Life" isn't evident. But we can the forwards half life of cities before 100, in 1980, is much less that backwards half life. Because that the new cities replace the old cities more fast.⑤The result of "Rank-Clock" about historical cities shows that the cities's ranks with political function are closely related to their political status. And the cities's ranks in the east and coastal areas of China are closely related to their geographical conditions and economic policy.