Abstract: Three treatments including air-circulating condensation dehumidification(condensation),soil mulching dehumidification(mulching) and gas exchange dehumidification(control) were set up to study in the temperature-maintaining effects of the air-circulating and regenerative dehumidification system inside Southern Chinese Greenhouses.The changes of the air and soil temperatures inside the greenhouses under the different conditions were observed.The results showed that in the sunny days during running time of dehumidification system,the air temperatures of the lower level inside the condensation greenhouse were significantly higher by 0.9~2.7 ℃ and 0.2~1.7 ℃ than inside the control greenhouse and the mulching greenhouse respectively.In the cloudy or on the rainy days,the air temperatures of the lower,middle and higher level inside the condensation greenhouse were also higher than or equal to that inside the mulching and control greenhouses.In the sunny days,the soil temperatures at 5cm,10cm,15cm,20cm depths inside the condensation greenhouse were higher by 1.0~2.1℃,1.0~1.5℃,1.2~1.5℃,and 1.4~1.6℃ than that inside the control greenhouse respectively.In January,the daily average air temperatures of the lower level inside the condensation greenhouse were higher by 0.1~2.3℃ and 0.1~1.5℃ than that in the control greenhouse and the mulching greenhouse respectively,while the number of days over 0.5℃ inside the condensation greenhouse were more 17 days and 18 days than that in the control greenhouse and the mulching greenhouse respectively.It was indicated that the temperature-maintaining effects of the air-circulating and the regenerative dehumidification system were significant in winter of the Southern China.

Key words: Southern Chinese Greenhouse, Southern Chinese Greenhouse, Air-circulating and regenerative dehumidification system, Temperature-maintaining