Season-Dependent Canopy Control of Understorey Microclimate and Thermal Comfort in a Peri-Urban Star Anise (Illicium verum) Plantation: A Two-Campaign Screening Study for Urban Climate Adaptation in Southern China

Peri-urban forests are valued as nature-based solutions for urban climate adaptation, yet seasonal canopy effects on understorey thermal comfort potential remain poorly quantified in production forests. In a peri-urban star anise (Illicium verum) plantation in southern China, we surveyed five purposively selected stands (144 trees, 446 hemispherical images, 150 microclimate runs) in spring and summer 2026, and screened understorey comfort potential using a preliminary Forest Wellness Potential Index (FWPI). Stand differences were weak in spring but pronounced in summer: understorey light, moisture and comfort potential all decreased with canopy openness under summer thermal load (exploratory Spearman ρ: −1.00 to −0.70; n = 5) but not in spring. Closed stands warmed by 1.8–1.9 °C between campaigns, whereas a recently crown-replaced stand warmed by 8.0 °C, its FWPI rank dropping from second to last. Because stands differ in age, management history and stem density, these contrasts are interpreted as associations within a management gradient, not canopy-only effects. The proposed screening workflow and four season-aware management principles—canopy continuity, compatible intercropping, staged crown renewal and seasonal scheduling—are preliminary hypotheses for multi-year, multi-site validation.