二氧化碳是绿色植物进行光合作用的主要物质 ,但大气中二氧化碳的含量一般为３００ ／ （毫克／公斤） ,这个浓度虽能使作物正常生长 ,但不是进行光合作用的最佳浓度。一般植物进行光合作用的最适浓度约为１０００ｍｇ／ｋｇ,远远超过了大气中的的正常含量。在棚（室）蔬菜栽 Carbon dioxide is a major source of photosynthesis for green plants. However, the amount of carbon dioxide in the atmosphere is typically 300 / mg / kg, which is the optimum concentration for photosynthesis, though it allows the crop to grow normally. The optimum concentration of photosynthesis of plants is about 1000mg / kg, far exceeding the normal content of the atmosphere. In shed (room) vegetable planted