Abstract:

In order to further enhance the thermal insulation properties and reduce the frequency of low temperature and solar radiation disaster occurred in the greenhouse, the tomato sunlit-greenhouse of Xuzhou was used as research object, using the greenhouse microclimate data collected from December 2010 to April 2011, according to the physical processes and mechanism of forming sunlit-greenhouse microclimate, different weather type about winter, spring and effect of different leaf area index on greenhouse energy distribution were studied systematically. The results showed that: with indoor total radiation changing, sensible heat and latent heat changed, sensible heat consumption was the main consumption in cloudy day, latent heat consumption was less than sensible heat consumption in the whole day; the energy used as crop evapotranspiration in fine day was significantly higher than that in cloudy day, while the consumed energy of indoor and outdoor tubular heat transfer was the opposite; with leaf area index increasing, the radiation reaching the earth surface reduced, the ground heating was slow, the exchanging quantity between indoor air and sensible heat of earth surface reduced, while the exchanging quantity between indoor air and sensible heat of wall increased. The results could provide a scientific basis for greenhouse structure optimization and sunlit-greenhouse management in winter and spring.