Uncovering urban functional areas differences through POI-based spatial metrics: evidence from Jianghan district, Wuhan

Urban functional areas (UFAs) exhibit strong spatial heterogeneity, and point of interest (POI) data represent valuable resources for capturing this variation. Although prior studies have mainly focused on using POIs to improve the accuracy of identification models, the underlying mechanisms by which POI characteristics distinguish UFAs remain underexplored. To address this, this study analyzed the differences in the characteristics of POI data across UFAs from three perspectives: density, diversity, and spatial distribution patterns. Moreover, to assess the positional relationships of POIs, the along-edge distribution index was developed. The results showed that POI characteristics differ markedly among UFAs. Density and diversity were the highest in commercial & business facilities and residential areas, whereas industrial land and green space & square areas exhibited sparse and homogeneous POI distributions. Spatially, POIs in residential and commercial & business facilities parcels were clustered, whereas those in administration & public services and green space & square areas were more dispersed. Regarding positional relationships, POIs in residential and street & transportation areas tended to align along parcel boundaries. These findings enhance our understanding of POI-based functional differentiation and offer practical insights into more interpretable UFA identification models and urban planning applications.