Abstract:
Abstract：Impervious surface is one of the key factors impacting regional spatial planning and ecological development, thus effectively indicative of change in urban development. As the central city of Huaihai economic zone, Xuzhou has been shifting its focus from rapid urbanization to ecologicalization; there, therefore, are broad implications for characterizing the dynamics of its urban impervious surface. In this study, we first identified the best impervious surface extraction approach by comparing four different impervious surface indices, namely ISA (Imperious Surface Area Index), BUAI (Built-up Area Index), BCI (Biophysical Composition Index), and ENDISI (Enhanced Normalized Difference Impervious Surface Index). By combining the fractal theory and a landscape ecology approach, we then analyzed the spatial-temporal heterogeneity of impervious surface of Xuzhou urban area (consisting of eight districts) from 2000 to 2007 and to 2017, from the perspectives of administrative division, profile lines, and landscape pattern indices, in order to characterize the dynamics of impervious surface in the context of urbanization, and provide suggestions for the future development of Xuzhou city. Results show that (1) BUAI can map impervious surface effectively and its resultant accuracy (Kappa coefficient=0.81) was by higher than the other three indices; that (2) while each district varied in impervious surface area with the Old City district (mainly for business and financial purposes) and Jinshanqiao district (the economic and technological development zone) having the highest proportions of impervious surface, growing impervious surface has been observed in the east and southeaster parts of the study area according to our BUAI based profile line analysis; and that (3) the impervious surface landscape pattern of the study area tends to be fragmented (from filled growth to dispersed expansion), complex, and irregular, suggesting its increased overall heterogeneity. Our study can provide a scientific basis for the urban development planning and land use planning.