Quantifying the Type of Urban Sprawl and Dynamic Changes in Shenzhen

Urban sprawl is a hot topic of global concern with increasing dramatically and impact on ecological environment. But there is not a mature method to explain the detail of process of urban sprawl and dynamic changes. In this paper, the dynamic changes of urban is studied based on 1980, 1988, 1994, 2000 and 2005 five remote sensing images of Shenzhen. It is distinguished three types including infilling, edge-expansion and outlying using six landscape metrics related to character the urban pattern. Combining urban sprawl type and urban pattern makes deepen understanding of urban expansion. The results show that the urban area of Shenzhen increases rapidly with growth rate and it experiences urban sprawl phase. In the early stage, it is at the diffusion period with the outlying area in dominant place in sprawl type and landscape fragmentation aggravation showed by NP, LPI increasing in pattern. With the infilling and edge-expansion area increasing rapidly, the urban sprawl turns into coalescence period with good landscape connectivity and landscape fragmentation remission. The method of combining type of urban sprawl and landscape metrics is useful to determine the time of urban sprawl phase. The results can help urban plan and design.