Spatial Association Rules and Thermal Environment Differentiation Evaluation of Local Climate Zone and Urban Functional Zone

Urban heat islands (UHIs) caused by urbanization have become a major issue affecting the sustainable development of the ecological environment. The distribution of UHIs is mainly affected by the reflection and transmission of heat radiation caused by differences in urban spaces, and the anthropogenic heat emissions caused by social activities. At present, the research on the urban thermal environment involves two spatial classification systems: local climate zone (LCZ), based on urban morphology and spatial patterns; and urban functional zone (UFZ), based on socio-economic activities. It is not clear whether there are association rules between these two systems in different cities. Against this background, this study explores the association rules between the UFZ and LCZ classification systems using the selected Chinese cities in different regions as typical examples. Our results confirm that there are common association rules from UFZ to LCZ, as the form of buildings is greatly influenced by the types of functional areas in urban construction. Specifically, the medical zone corresponds to the compact mid-rise zone (LCZ2); the business service area and the office area also correspond to the compact zone (LCZ1-LCZ3); and the industrial area corresponds to the compact low-rise zone (LCZ3). These functional zones have the same association rules in different cities. The cross-regional mining of the relationship between different urban functional systems will help to coordinate different planning departments and carry out the integration of multiple spatial plans. Furthermore, we found that LCZ has a better differentiation effect on the surface temperature through our comparison research, which makes it more suitable as a reference for research on the thermal environment and the heat island effect.