An experiment was conducted to determine the extent to which the distribution of CO2 depended on the thermal conditions within a greenhouse. The CO2 levels and the change in the horizontal temperature gradient were measured throughout the greenhouse. The appropriate level of CO2 and the concentrated mass of CO2 were analyzed at predetermined points to verify the relation between CO2 and temperature to establish whether a constant distribution existed throughout the facility. As a result, when using the membrane system, the CO2 concentrations external and internal to the greenhouse were measured to be 380~440 ppm and 1020 ppm, respectively. The efficiency of the membrane system was shown to be about 268%. The highest CO2 concentration was about 1000 ppm near the floor, where the temperature was the lowest. In contrast, at a height of 2.50 m, where the temperature was the highest, the CO2 concentration was the lowest at about 400~500 ppm.
Tropical Agricultural Research Vol. 26 (4): 714 – 720 (2015)