Globally, cultural heritage renewal has become an important strategy for promoting economic development. However, against the background of persistent urban shrinkage, built heritage conservation faces severe challenges. Taking provincial-level historical and cultural districts in Liaoning Province as the research object, this study conducts field investigations and semi-structured interviews with residents, and applies grounded theory to construct an explanatory relational framework for heritage conservation dilemmas in shrinking cities. It aims to answer the question of how conservation dilemmas in historical districts are formed under urban shrinkage. The findings show that, in shrinking contexts, growth-oriented conservation systems face structural maladaptation, and Government Support, Economic Conditions, Service Level, and Heritage Resources exhibit cumulative associations. This is manifested in a main explanatory pathway of ‘weakened Government Support–strained Economic Conditions–declining Service Level–degradation of Heritage Resources’: (1) fiscal contraction and institutional maladaptation constrain the capacity of government support; (2) weakened government support and shrinking demand jointly undermine the market foundation of historical districts; (3) declining market activity and sustained population outflow jointly weaken public service provision and community networks, further resulting in the decline of social functions and spatial vitality in historical districts. Based on these findings, this study proposes a smart-shrinkage-oriented response framework. Under the premise of accepting population decline and economic contraction, the framework seeks to optimise the allocation of limited resources through differentiated conservation, low-cost maintenance, and incremental reuse. This study provides empirical evidence for understanding the formation process and governance pathways of built heritage conservation dilemmas in the context of urban shrinkage.

To address social challenges arising from extensive exploitation of rural tourism resources—including degradation of natural ecosystems and erosion of ethnic cultural heritage—this study establishes a synergistic assessment framework constrained by habitat quality, resource endowment, and facility accessibility. By integrating the InVEST model, kernel density function, and cumulative cost distance algorithm, we developed a spatial overlay analysis tool to evaluate these three dimensions in the dry-hot valley of Lujiang Dam (LJD) within China's Nujiang River Basin. This approach identified natural spatial suitability for tourism development (NSSTD). Key findings reveal that LJD exhibits high overall habitat quality (844.88 km², 64.55% of total area), yet demonstrates pronounced spatial heterogeneity—prime habitats concentrate in western and southeastern sectors, contrasting with a central low-quality habitat belt. Natural/cultural resources display a barbell-shaped spatial configuration, clustering at southern and northern extremities. Tourism accessibility manifests concentric spatial patterns, with 88.08% of resources accessible within 90-minute travel thresholds. NSSTD zones (54.74 km²) predominantly located in southern LJD encompass 17 land-use types and 70.73% of villages. These results provide critical spatial decision-making support for: Sustainable tourism resource management in dry-hot valleys, precise village planning, territorial spatial optimization strategies. The methodology demonstrates operational value in balancing ecological conservation and rural development priorities.