Cooling Performance of Landscape Element Combinations: A Multi-Dimensional Outdoor Thermal Comfort Assessment in Urban Parks of Zhengzhou, China

Urban parks have been widely recognized for their cooling potential; however, the regulatory effects of landscape element combinations on outdoor thermal comfort (OTC) in urban parks remain insufficiently quantified from a systematic, multi-dimensional perspective. Focusing on three representative urban parks in Zhengzhou, China, this study combines microclimate field measurements and questionnaire surveys conducted during the summer midday period to assess the regulatory effects of ten landscape element combinations on OTC across the physical, physiological, and psychological dimensions. Under summer midday conditions, OTC differences related to shading condition were generally more pronounced than those related to ground surface type or proximity to water bodies, with consistent trends across all three dimensions. Across comparable grass-covered and stone-paved combinations without adjacent water bodies, physiological equivalent temperature (PET) was 14.9–25.8 °C lower under dense tree shade and 11.9–23.9 °C lower under sparse tree shade than under unshaded conditions. This study further provides indicative estimates of summer midday thermal comfort reference thresholds for urban parks in Zhengzhou based on PET, including an extrapolated neutral PET reference value of 20.3 °C, a neutral PET range of 13.6–27.0 °C, and a thermal acceptability range of 15.4–36.2 °C. The multi-dimensional assessment advances understanding of the effects of different landscape element combinations on OTC and provides a transferable analytical approach for context-specific OTC research across different regions and urban park types.