ABSTRACT
Moreover, the connectivity and the accessibility of the urban hierarchical tree of Beijing were decreasing from the top to the bottom, which indicated that the interactions between urban development centers were decreasing along with the sizes. On the other hand, the diversity of the urban hierarchical structure was measured by the index of uncertainty. In general, the uncertainty decreased from the top hierarchy toward the bottom hierarchy. In other words, the diversity of patch compositions was diminishing from the top to the bottom. Furthermore, the uncertainty index was also meaningful at a given hierarchical level. For instance, the high uncertainty (e.g., 4.3 for Patch 3 at the third level on Figure 5b) indicated that the patches located in that sub-region and connected to the same local core patch displayed distinct spatial patterns. In other words, there existed obvious spatial disparity of urban growth in that sub-region. For instance, several growth centers were clustered near the west vicinity of Patch 3 (Figure 5b).
