PROGRESS IN GEOGRAPHY ›› 2010, Vol. 29 ›› Issue (10): 1193-1200.doi: 10.11820/dlkxjz.2010.10.006

• Original Articles • Previous Articles     Next Articles

Constraint Mechanism of Excessive Urban Spatial Expansion in the Context of Large-scale Urban Construction Investment: A Case Study of Wuxi

YANG Shan1, ZHOU Lei1, CHEN Sheng1, JI Zengmin2   

  1. 1. School of Geography Science, Nanjing Normal University, Nanjing 210046,China;
    2. Department of Cultural Information, Sugiyama University, Nagoya 464-8662, Japan
  • Online:2010-10-25 Published:2010-10-25


The economic stimulus package with large-scale urban construction investment, launched by the government in 2008, will not only play a significant role in promoting the economic development, but also lead to the excessive urban spatial expansion. Due to the scarcity of arable land resources in China, the excessive expansion of urban space will be a threat to the national long-term interests. This paper analyzes the relationship between urban construction investment and urban spatial expansion by establishing an AC-D model, and taking Wuxi as an example, and verifies the role of urban construction investment in promoting urban spatial expansion. By entering the data of urban spatial expansion and statistics of Wuxi (1991, 1998, 2001, 2005, and 2008) into AC-D model, this paper calculates the effects of urban construction investment on urban expansion, and finds a significant role of urban construction investment in promoting urban spatial expansion. The elasticity coefficient (α) between total urban construction investment and urban spatial expansion reaches 0.619. Furthermore, the paper calculates the contribution rates of urban construction investment in different directions to urban spatial expansion in Wuxi, and the result shows that investment in different fields will cause different degrees of expansion of urban space. On the basis of these studies,this paper builds up an urban construction investment structure optimization GA model based on genetic algorithm, which is under the constraints of GDP, urban area and population. The results show that a moderate amount of investment in the five areas with significant impacts on urban spatial expansion of Wuxi is about 277.6 billion Yuan in 2009 and 2010. Investment in excess of this size will cause excessive urban spatial expansion. The investment required for manufacturing, transportation, warehousing and postal industries, real estate investment and construction should be properly controlled, and the investment in water conservancy, environment, education, health, social security and social welfare industries to protect and improve people's livelihood should be increased. So this paper provides a scientific ground for urban construction investment and sustainable development.

Key words: AC-D model, constrained mechanism, GA model, urban expansion, construction investment, Wuxi