A Multi-Sensory Value Perception Deep Map model for smell–sound heritage in historic districts

Historic districts embody heritage value beyond visual form, yet quantitative assessment has overlooked soundscape and smellscape. This study proposes a Multi-Sensory Value Perception Deep Map (MVC-DepthMap) model integrating soundscape, smellscape and Historic Land-Use Assessment to quantify sensory heritage value through Time Depth and Historical Richness. Using Kunming Old Street as a case study, data from soundwalks, smellwalks, questionnaires and interviews were analysed with GIS. Results reveal a spatial pattern of core-node clustering, traditional-lane extension and peripheral decline. The Yunnan Confucian Temple, Guanghua Street East and Wenming Street form high-value clusters (MVC = 1.00, 0.65 and 0.65). Significant sound–smell interaction effects were observed: “traditional vending calls–food aromas” and “temple bells–incense smoke” produced sensory synergy, whereas “modern traffic noise–historic odours” generated sensory conflict. The model supports differentiated conservation and inclusive urban regeneration.