The delimitation of urban growth boundaries using the clue-s land-use change model: Study on Xinzhuang town, Changshu City, China

Over the past decades, urban growth boundaries (UGBs) have been regarded as effective tools applied by planners and local governments to curb urban sprawl and guide urban smart growth. The UGBs help limit urban development to suitable areas and protect surrounding agricultural and ecological landscapes. At present, China's Town and Country Planning Act officially requires the delimitation of UGBs in a city master planning outline and in central urban area planning. However, China's practices in UGBs are usually determined by urban planners and local authorities, and lack a sound analytical basis. Consequently, Chinese UGBs are often proven to be inefficient for controlling urban expansion. In this paper, take the fast-growing Xinzhuang town of Changshu city, eastern China as an example, a new method towards establishing UGBs is proposed based on land-use change model (the Conversion of Land Use and its Effects at Small regional extent, CLUE-S). The results of our study show that the land-use change and urban growth simulation accuracy of CLUE-S model is high. The expansion of construction land and the decrease of paddy field would be the main changing trends of local land use, and a good deal of cultivated land and ecological land would be transformed into construction land in 2009-2027. There is remarkable discordance in the spatial distribution between the simulated UGBs based on the CLUE-S model and the planned UGBs based on the conventional method, where the simulated results may more closely reflect the reality of urban growth laws. Therefore, we believe that our method could be a useful planning tool for the delimitation of UGBs in Chinese cities..