Soil heating by solarization inside plastic greenhouse in Santa Maria, Rio Grande do Sul, Brazil

Solar heating of soil by mulching with transparent polyethylene (known as soil solarization) is a physical method of soil disinfestation. The increase in soil temperature by solarization inside a plastic greenhouse in Santa Maria, Rio Grande do Sul State, Brazil, was measured. It was estimated the time which soil temperature exceeded some thermal levels in solarized soil, During the 1992/1993 and 1993/1994 summers, experiments were carried out in a 10 m × 25 m plastic greenhouse. Soil temperature was measured at 2 cm, 5 cm, 10 cm, and 20 cm depths in one solarized and uncovered plot. An increase of 10°C or more was observed in solarized soil at 2 cm and 5 cm depths in comparison to the bare soil. Soil temperature exceeded 50°C or more several days during 1993/1994 up to the 10 cm depth. The estimated exposure time at several thermal levels in solarized soil allow to conclude that solarization presents potential in the region.