An Empirical Study on the Interaction and Synergy Effects of Park Features on Park Vitality for Sustainable Urban Development

Parks, as essential elements of urban green public spaces, play a crucial role in sustainable urban development. Their features have features confirmed to significantly affect park vitality. Prior research has indirectly indicated that park features might impact park vitality via interaction and synergy; however, such effects have been neglected in park vitality studies. The study area is South China, with data collected from 20 urban comprehensive parks in 8 representative cities. This study constructs linear mixed models of principal component main effects, interaction effects, and synergy effects to empirically examine the interaction of internal element features and the synergy of external environmental features affecting park vitality. The findings indicate: (1) Structural interaction effects exist among internal element features that impact park vitality. The structures of “medium plaza + small plaza” and “primary park road + open grassland” significantly enhance vitality. Conversely, the structure of “aquatic plant coverage area + lake + dense woodland” has a negative influence. Single structure features are ineffective in significantly influencing park vitality. (2) The inclusion of interaction terms between internal feature structures enhances the significance of their effects on vitality. The interaction of “medium plaza + small plaza” × “primary park road + open grassland” shows the strongest effect. (3) There is a synergy between internal and external features: with external features like accessibility and disposable income, certain internal interaction structures positively contribute to vitality. Additionally, the “service capacity” external environmental feature exhibits a negative synergy with internal element features. These findings provide theoretical and practical insights for sustainable urban park design, planning, and refined management in cities with similar socioeconomic and spatial contexts.