A Cross-county Study On The Evolution Of Spatial-temporal Patterns Of Urbanization

Urbanization is such a process that rural population and non-agricultural industries agglomerate to the urban area, resulting in the development of industrialization. The level of urbanization in a region essentially reflects the level of economic development and social progress there. Therefore, how to promote the steady urbanization in a country becomes the government’s strategic thought since such process plays a political role that realizes the coordinated development of economic, population, natural resources, and environment. Chengdu-Chongqing economic zone, as the most advantageous, vigorous, and development potential area in the western region of China, has been the economic center and growth pole for that region. The development in such zone is expected to promote the overall growth of economic for Western China. Whereas, in the process of urbanization development, ChengduChongqing economic zone has been facing with some difficulties along with the local urbanization in this area, such as peri-urbanization, low level of urbanized population, the imbalance between urbanized population and urban land resource, the structural maladjustment of industry, and the unreasonable urban system. Such difficulties have become the bottleneck to restrict the socioeconomic development in the zone. So, it is meaningful to study the conditions of the local urbanization process, including the spatial-temporal evolutionary characteristics, in Chengdu- Chongqing economic zone.This research constructed the indictor system for assessing county-cross urbanization level in Chengdu-Chongqing economic zone by integrating population urbanization, economic urbanization, and social urbanization in Chengdu-Chongqing economic zone. In detail, the entropy method was applied to estimate the weight values; then, the levels of urbanization in 2002, 2007, and 2012 cross counties were calculated respectively. The degree of differentiation between the levels of urbanization cross counties was measured by different approaches, including range, standard deviation, coefficient of variation, and Thiel index. Assisted by some GIS and ESDA(exploratory spatial data analysis) software such as Arc GIS and Geo Da, the characteristics, heterogeneity, and correlation of spatial differentiation, and the evolutionary law were examined as well.The research indicated that:(1) From 2002 to 2012,the absolute gap between levels of urbanization cross counties in Chengdu-Chongqing economic zone was expanding, while the relative difference was reducing.(2) The differenced among the county urbanization levels in Chengdu-Chongqing economic zone was mainly caused by the internal difference within Chengdu plain economic belt; such local factor occupied the contribution rate over 50%. Meanwhile, the external difference between the economic belts was also expanding.(3) The spatial pattern of county urban levels in Chengdu-Chongqing economic zone has transformed from “low value aggregation, high value dispersion” to “dual-core of high value”.(4) From 2002 to 2012, the urbanization gravity center, economic gravity center, and society gravity centers were all moving along the “development axis of Chengdu-Chongqing” and toward to the geometric gravity center, which presented a “southeast to northwest” trend. Such tendency was related to the growing power of economic aggregation in the City of Chongqing after it became the direct jurisdiction of the central government in China. But the population gravity center was moving toward the side of Chengdu instead, which was because of the competitive advantage in tertiary industry in the City of Chengdu.(5) From 2002 to 2012, the spatial autocorrelation for the county urbanization levels in Chengdu-Chongqing economic zone was significant, showing a pattern of high value aggregation and low value aggregation. The Chengdu plain economic belt and Chongqing economic belt were the “high-high” aggregating areas, while the “low-low” area was located at the central region between the two belts. Entirely, the spatial pattern presented an inclined “8” shape. In order to promote the urbanization cross counties in Chengdu- Chongqing economic zone, some policies were proposed in the research: first, unbalanced development strategy for different areas should be implemented. Second, population urbanization can be realized by developing industry at different area, which can promote the rural population transfer at local. Third, some supporting policies such as land resource management and social security should be improved to solve the issues associated with the rural population transfer.