CO₂ Environment

Abstract

Carbon dioxide concentration in the air is another important factor for plant growth. The CO₂ concentration in the open air varies daily. On a sunny day the CO₂ level is fairly constant around 300 to 350 µl/l due to photosynthesis by plants, and it rises to around 400 to 450 at night. The CO₂ level is more important under cover, especially in plastic houses where air exchange is normally restricted in order to raise temperatures in a cold climate. As a result, the carbon dioxide concentration falls below the outside level during the daytime due to photosynthetic CO₂ uptake. Therefore, sometimes CO₂ enrichment is conducted in plastic houses.