Relations between Plant Coverage and Soil Temperature beneath Film Mulch with Different Size of Planting Hole

摘要

The purpose of this paper was to clarify the effects of planting hole diameters of mulch film and plant coverage on soil temperature beneath mulch film. At both 6:00 and 15:00, the soil temperature in mulched zones decreased more when the plant coverage was higher and the soil temperature in the control zone (bare plot) was higher. No significant difference, however, was observed between zones with different planting hole diameters. The soil temperature differences between zones are significantly affected by air temperature, soil moisture tension and plant coverage. In vegetation zones, the daily range ratio of the soil temperature was the smallest in the zone with 3 cm diameter planting holes (Mp_3). The daily range ratio of soil temperature in allvegetation zones, except the Mp_3 zone, was affected by three factors: daily average air temperature, daily total amount of solar radiation and daily average wind speed.