Open space fragmentation in Hong Kong's built–up area based on spatial horizontal and vertical equity lenses

Abstract

Urban studies attempt to assess open space fragmentation and develop sustainable policies in high–density cities. However, it is unclear whether open space fragmentation has widened existing spatial inequalities. Thus, this study first proposes a theoretical framework of open space fragmentation and its associated spatial equity issue in towns at different stages of urbanisation development. Due to the acute shortage of open space and continuing urbanisation, Hong Kong’s built–up area provides a suitable case to unravel this issue. The characteristics of open space fragmentation forms in old and new towns are elaborated through landscape pattern analysis and principal components analysis. Spatial horizontal equity and spatial vertical equity based on demographic characteristics and social economic status are portrayed by means of the Theil index and spatial matching. The results reveal that open space fragmentation takes the form of morphological (use, internal, extensive and shape) and connectional (location) fragmentation. Open space fragmentation shows spatial heterogeneity, as evidenced by the highest fragmentation index of 0.259 in the Kowloon region, followed by the Hong Kong Island and the New Territories regions. Additionally, internal fragmentation overall is embedded in more spatial horizontal inequalities, and there is a higher level of spatial horizontal inequality in old towns than in new towns. Vulnerable groups that rely more on open spaces, including children, the elder, low education groups, immigrant groups and unemployed groups, suffer more from spatial vertical inequalities in old towns than in new towns. The findings inform refined open space management in high–density cities.