Shape-weighted landscape evolution index: An improved approach for simultaneously analyzing urban land expansion and redevelopment

Urban redevelopment and the improvement of urban green coverages have become an important form of urban landscape evolution and have led to a decline in imperviousness. However, in the quantitative analyses of landscape patterns, such form has not been as widely considered as urban expansion dynamics represented by the growth of impervious surfaces. Furthermore, existing metrics ignore the different patch shapes in the identification of spatial evolution types, thereby significantly affecting the recognition of spatial relationships between new and existing patches. This study proposes a shape-weighted landscape evolution index (SWLEI) for simultaneously analyzing the landscape expansion and shrinkage types of patches in two or more periods. Compared with existing landscape expansion metrics, the SWLEI can depict the spatial relationships between new and old patches from a more detailed perspective and is thus more comprehensive and meaningful in terms of geospatial recognition. Empirical analysis in Hubei Province in central China indicated that dramatic urban expansion and small-scale urban built-up land use change occurred in 1990–2015. The changed urban patches can reflect the spatial patterns and distribution of urban redevelopment, and indicate the characteristics of the spatial optimization of urban land uses and urban greening. The characteristics of urban expansion and redevelopment patterns showed a distinctive disparity in different cities and periods. Urban growth became increasingly compact after 2005, and most cities experienced redevelopment at the early stage of urbanization and after 2005. Furthermore, the newly developed and changed urban patches were clustered in the central and eastern areas with advantageous physical and economic conditions.