Dynamic Detection on Urban Sprawl Based on RS and GIS: A Case Study of Chengdu City

With the development of society and economy, the rapid urban sprawl in land use is being witnessed of late in urban districts. As a result, many problems in society and environment have appeared in urban districts, such as population expansion, air pollution, etc. Assessment and inventory on urban sprawl is essential for city planning and sustainable development. The objective of this study was to detect the urban sprawl of Chengdu city (1992-2006) following the RS (remote sensing) and GIS technique. RS data provided valuable information for understanding and monitoring the process of urban land cover changes. RS and GIS is gaining importance as vital tool in the detecting on urban sprawl of cities based on RS data. The urban sprawl area extracted from RS data of Chengdu city is 9882.808hm², 2.686 times 10⁴ hm² in 1992, 2006, respectively. The result shows that the Chengdu city is expanding in different directions resulting in large-scale urban sprawl and changes in urban land use, the spatial pattern of such changes is clearly noticed on the urban fringes than in the city centre.