Assessing the fragmentation of construction land in urban areas: An index method and case study in Shunde, China

The fragmentation of construction land due to decentralised urban development, disorderly mixed land use, and large-scale transportation infrastructure poses a threat to urban integrity. There is a need to quantify the fragmentation level in a consistent way for inclusion in planning-related decisions. In the context of China's urban sprawl, this study develops a quantitative and intuitive index approach that planners can use to analyse multiple fragmentation features of construction land within urban areas. The approach can be used in planning policy reviews for timely land-use assessment and can be integrated into urban planning processes for developing strategic land-use scenarios. The method was applied in Shunde, a typical urban area in southern China, and construction-land fragmentation and its impacts on environmental quality were analysed. The results show that the entire built-up area in Shunde displays a high level of fragmentation. Patches of industrial and rural residence have been identified specifically higher fragmentation level. The shortage of available construction land makes land consolidation within built-up areas very important in planning Shunde's future development. Moreover, the land shortage requires the progressive reduction of construction land fragmentation. The results of the study also indicate that although land fragmentation has been affected by transportation infrastructure and the existence of rivers and hills in this region, decentralised decisions from hierarchical local governance regimes have greatly exacerbated this situation. Shunde provides examples of typical land-use problems associated with quasi-urbanised regions in China; construction-land fragmentation is a greater determinant for the sustainable development of urban and rural areas than construction-land growth.