Study on Soil Temperature and Its Influencing Factors in Northern Winter Solar Greenhouse With Drip Irrigation

Taking sweet pepper that cultivating in autumn and winter in solar greenhouse as material,by field experiment, the soil temperature change in solar greenhouse with drip irrigation under plastic film was studied during the growth period of pepper under the condition of four different soil water treatments,and the relationship of soil temperature andenvironmental factors and their comprehensive effects were analyzed by path analysis method.The results showed that the temperature of different treatments reduced,with the increasing of irrigation water quota.The temperature of surfacelayer soil reduced quickly and the range of its temperature was larger.And with the increasing of soil depth,the soil temperature increased slowlier and its range decreased,and the peak soil temperature of different layers appeared delayed. The relationship of soil temperature and the soil depth were exponential,and the correlation coefficient of each treatments reached the maximum at 15:30;the average soil temperature of 25cm depth reduce with the increasing of irrigation quota,and irrigation water quota had a direct influence on the correlation between soil temperature and the depth of soil; the correlation coefficients of soil moisture content,the air temperature and soil temperature in solar greenhouse was-0.7574and 0.6512respectively,directly action coefficients of path was-0.7021and 0.6172respectively,which showed that the both soil moisture content and the air temperature in solar greenhouse had greatly effect on soil temperature.