Recreational Space Configuration, Perceived Time Cost, and Recreational Travel Carbon Emissions: Mediation Evidence from Tianjin, China

Leisure space configuration has been recognized as a spatial approach to reducing carbon emissions from recreational travel, but the role of perceptual factors in linking inter-facility distance to travel behavior is not fully clear. This paper adopts a “relative distance–perceived time cost (PTC)–carbon emissions” framework to explore their associations. Based on 20 recreational hotspots in Tianjin and 2372 valid questionnaires, we apply correlation analysis, mediation tests and regression tree segmentation for empirical exploration. Results indicate that the maximum distance between commercial and other leisure facilities (ShopMax) correlates significantly with PTC and shows a potential indirect association with carbon emissions. The indirect effect is significant for single-point trips (p = 0.006), while only directional trends exist for chained trips due to sample constraints. Optimal distance intervals present nonlinear differences across facility types: scenic facilities (ScenicMax) have overlapping perception- and emission-friendly intervals, whereas ShopMax shows divergent intervals for chained trips. The 200–300 m range is consistently found to be a high-carbon zone. This exploratory analysis suggests perceived time cost may connect spatial configuration to low-carbon travel. Differentiated layout strategies warrant further exploration for various facilities and travel contexts.