Rapid urbanisation has generated numerous environmental consequences, particularly regarding open space fragmentation. Open space fragmentation is the transformation of open space from a state of homogeneity, integration, and continuity to a state of heterogeneity, division, and incoherence. Nevertheless, one main obstacle to understanding this issue is how to address the spatial heterogeneity of the impact of urbanisation on open space fragmentation. Thus, this paper provides a comprehensive framework for the mechanistic associations between open space fragmentation and urbanisation in Hong Kong’s built-up area. The results illustrate that both open space fragmentation index and urbanisation index values are noticeably higher in dense urban areas. Land urbanisation, represented by the percentage of construction land in total land, has the highest explanatory power for spatial differentiation in open space fragmentation, followed by social and population urbanisation factors. Furthermore, the relational interrelations of open space fragmentation drivers are the bivariate and nonlinear enhancement interactions. Social urbanisation and land urbanisation have the strongest bivariate enhancement interaction for the use fragmentation form and the largest nonlinear enhancement interaction for the internal fragmentation form. Based on initial urban planning, open space fragmentation is an adaptation outcome of population, land, and social urbanisation factors, and this self-organisation phenomenon has been further emphasised in the historical process. These insights significantly enrich our understanding of how urbanisation affects open space fragmentation and provide valuable guidance for better open space strategies.

Healthy City policies are often enforced based on expert assessments, which calls for research on the presence and occurrence of mismatches between experts’ and public opinions. Additionally, the unique challenges in small and midsized cities (SMCs) are often ignored. In this study, we compared the values of experts and the public on achieving a healthy SMC. A survey with both experts and public participants was conducted. An explorative factor analysis (EFA) and fuzzy synthetic evaluation (FSE) were adopted to identify the key factors and their importance hierarchy. Both the experts and the public highlight the importance of Environmental Quality and Governance/Service (EQ). More attention could be given to public participation and urban form to reflect the public’s perceptions better, as they prioritized these factors more than the experts did. Both similarities and mismatches between experts and the public were revealed in this study, indicating that more studies are necessary to understand heterogeneous values and achieve mutual understanding. Thus, public participation and involvement are recommended to construct a Healthy City for more comprehensive benefits. Our results also offer valuable insights from the public to plan Healthy Cities in the future, avoiding reactive decision making.

Urban heritage revitalization relies on public cultural cognition, yet the psychological impact of spatial morphology remains under-quantified. This study integrates space syntax with survey data to evaluate the relationship between five spatial metrics and six cultural dimensions, including authenticity, integrity, vitality, involvement, diversity, and identity, across three heritage cases. Correlation and clustering analyses reveal that spatial configuration dictates distinct cultural cognitions rather than universally positive effects. This study identified three spatial–cultural typologies: an authentic traditional revitalized area, where high visual entropy preserves authenticity but limits involvement; a high-quality hub, which utilizes high integration and connectivity to holistically enhance all cultural cognitions; and a functional and vital art area, where spatial control for modern vitality is maximized at the expense of historical identity. These findings demonstrate that morphological variables serve as active, quantifiable predictors of cultural impact, moving the discourse of space and culture from a metaphor to an empirical framework. This study provides actionable design strategies for balancing functional efficiency with historical preservation in sustainable urban (re)development.