ABSTRACT:Urban expansion displays different characteristics in each period. From the perspective of the urban agglomeration, studying the spatial and temporal characteristics of urban expansion plays an important role in understanding the complex relationship between urban expansion and network structure of urban agglomeration. We analyze urban expansion in the Yangtze River Delta Urban Agglomeration (YRD) through accessibility to and spatial interaction intensity from core cities as well as accessibility of road network. Results show that: (1) Correlation between urban expansion intensity and spatial indicators such as location and space syntax variables is remarkable and positive, while it decreases after rapid expansion. (2) Urban expansion velocity displays a positive correlation with spatial indicators mentioned above in the first (1980)(1981)(1982)(1983)(1984)(1985)(1986)(1987)(1988)(1989)(1990) and second (1990)(1991)(1992)(1993)(1994)(1995)(1996)(1997)(1998)(1999)(2000) period. However, it exhibits a negative relationship in the third period (2000)(2001)(2002)(2003)(2004)(2005)(2006)(2007)(2008)(2009)(2010), i.e., cities located in the periphery of urban agglomeration developing more quickly. Consequently, the hypothesis of convergence of urban expansion in rapid expansion stage is put forward. (3) Results of Zipf's law and Gibrat's law show urban expansion in YRD displays a convergent trend in rapid expansion stage, small and medium-sized cities growing faster. This study shows that spatial linkage plays an important but evolving role in urban expansion within the urban agglomeration. In addition, it serves as a reference to the planning of Yangtze River Delta Urban Agglomeration and regulation of urban expansion of other urban agglomerations.

ABSTRACT:Spatial analysis is the key content of GIS basic theory course. In this paper, the importance of practice teaching for GIS spatial analysis theory studying and its implementation method are discussed combined with practice teaching arrangement of spatial analysis in the course "GIS theory and practice" based on the basic principle of procedural teaching theory and its teaching model. In addition, the concrete gradual practice process is mentioned in four aspects. By this way, the GIS spatial analysis theory studying can be deepened and the cultivation of students' comprehensive ability of Geography Science can be strengthened.* Corresponding author. This is useful to know for communication with the appropriate person in cases with more than one author.