Anaysis of Urban Land Expansion and Its Driving Forces in Beibei District, Chongqing Municipality
大都市卫星城镇用地扩张及其驱动力分析——重庆市北碚区为例

Beibei District is one of cities in the coastal zonal areas of Chongqing Municipality, showing the fastest urban land expansion. Rapid urban land expansion, especially occurring since the 2000s, has resulted in change in the economic structure over there. With the significant economic shift, the area of urban land use has also increased. Its developmental characteristics and land use change are typical in satellite towns of metropolis in southwestern China. Most of satellite towns of metropolis have experienced the same political, economic, and technical reforms and advancements. This paper presents an integrated study of urbanization trends in Beibei using geographical information systems (GIS) and remote sensing. Remote sensing provides spatially consistent data sets that can cover large areas with both high spatial and temporal resolutions. These advantages are unique in detecting spatial and temporal dynamics of processes in urban growth and land use change. Integration of remotely sensed data and global positioning system (GPS) with GIS has been a trend in comprehensive assessment of land cover change in a more effective and efficient way. It has been proved useful in mapping urban areas and analysis and modeling of urban growth and land use change. Based on integrated analysis of GIS and remote sensing, we unraveled a trend in urban land use expansion and suggested the primary driving forces of this trend in Beibei, a satellite city of Chongqing. Spatial and temporal variations in urban land use expansion through 1972 to 2006 corresponded to land use/land cover change (LUCC). Characteristics of LUCC in Beibei are: 1) temporally, the urban land use expansion can be generally classified into three stages, i.e., slow, fast, and dramatic expansion. The fast and dramatic expansion was clearly observed in southwestern part of the city. The downtown of the urban area shifted from the south and the southwest; 2) three types of spatial pattern of urban growth in Beibei include normal urban growth, social-political intervention, and economic-population intervention; 3) changes in spatial pattern of urban growth suggest that the urban land use expansion played a dominate role in LUCC; and 4) constrained by physical geography characteristics (mainly the river and mountains), the urban land use expansion in Beibei seems to be typical in the same type of satellite city. On the other hand, economic, political, public transportation, and population growth also contributed to the urban land use expansion of varying degrees.