Early-Winter Thermal Responses of East–West and North–South Tomato Ridge Layouts in a Chinese Solar Greenhouse

This exploratory study compared early-winter thermal conditions in east–west (E-W) and north–south (N-S) tomato ridge blocks within one Chinese solar greenhouse from 22 November to 3 December 2025. A thin-film partition separated the blocks. We measured canopy-air, soil-surface, plastic-film, north-wall, and rear-slope temperatures and used transient computational fluid dynamics (CFD) to interpret spatial patterns. Mean canopy-air temperatures were 15.34 °C (E-W) and 15.22 °C (N-S), whereas mean soil-surface temperatures were 14.43 and 13.31 °C, respectively. On a representative cloudy day, daytime soil-surface temperature was 2.48 °C lower in the N-S block. The CFD model reproduced broad surface-temperature cycles on both representative days; canopy-air comparison was restricted to the sunny day from 12:30 to 21:00. Under the tested operating conditions, layout-related contrasts were more evident at the soil surface than in mean canopy air. Because the comparison involved two unreplicated blocks within one greenhouse and did not include crop-response measurements, these findings should be interpreted as exploratory thermal associations rather than evidence of a general causal or agronomic advantage of either ridge orientation.