Measurement Of The Urban System Temporal Evolution Of Jiangsu Province Based On Fractal Theory

Principles of modern urban development in China are following the guidance of urban scale after its establishment. As one of the quickest and most dynamic province in social economic growth in China, urbanization level of Jiangsu has been keeping promoted since the Reform and Opening-up. Went through the south Jiangsu development model in 1980s, external-oriented urbanization in 1990s and large urbanization strategy in 2000s, Jiangsu is now in top speed of the whole nation in the process of urbanization. In 2008, its urbanization level was up to 54.3%, almost 8.6% advanced to the country's average number. However, beneath the surface of a rapid growth, there are still insidious flaws such as contradiction between urbanization development velocity and quality, enlargement of regional imbalance, disparity in urban and rural area, inequality function of urban system, which all call for re-examinations on the urban scale strategy, especially for decent realization of the concept on urban system. Based on the fractal theory in urban geography, this paper takes the city-size distribution and allometric growth relationships between area and population as the starting point, gives an empirical research at provincial and city levels on the population scale and its relationship between expansions of urban construction land in urban system of Jiangsu Province.Urban system is consisted of cities with different function, scale and structure, which are closely tied up and mutually dependent in areas integrative. Meanwhile, as a self-organization, it is marked by characteristics of wholeness, hierarchy, ordering, dynamics, and openness. In this paper, regional non-agricultural population, built-up land acreage of cities and counties in Jiangsu over 1996～2008 are taken as the major data source, methods of rank-size rule, law of allometric growth and its multi-fractal property are employed to analyze fractal feature of city-size distribution, index scale and degeneration of population-area allometric growth in dimension of phase and ordering space. The results indicate:(1) urban system of Jiangsu Province is now in good gear, its rank-size structure is in a centralized-to-decentralized period of transition; (2) the monopolies of primacy city are not as strong as they used to be, but large scale cities remain the dominating force to speed up the process of urbanization, which would wider the regional gap henceforth; (3) allometric growth relationship between urban land and population is in trends of degeneration at provincial level, which turns negative to positive after 2001, and cities except Huaian and Yancheng are all in semi-degeneration relationship of allometric growth; (4) scale factors of allometric growth of Xuzhou, Lianyungang, Suzhou and Nanjing mark higher than other cities in an obvious way, which imply faster urbanization of spatial expansion than population growth in these cities. Further research shows that gap between land and population urbanization grows quickly.Fractal theory in urban geography is one kind of science methods for geographical spatial information analysis, which provides a powerful tool for complexity exploration. Proceeded with the feature of nonlinear, this paper not only uncovers principles of urban system without abstracting the model of targets, but also achieves creditable conclusions without losing too much geographical information, which offers a profitable experiment for the info-science in the information era.