在低温季节,塑料大棚内由于经常密闭保温,通风不良,很容易造成有害气体的危害,严重时甚至会使棚内的蔬菜在一夜之间枯萎,所以应特别注意预防。大棚中有害气体的发生,首先是由于施肥技术不当,特别是在氮素化肥用量大,或干施作追肥时,最易产生有害气体,此外,应用大量的新鲜厩 In the low temperature season, the plastic greenhouse is often closed and insulated, poor ventilation, it is easy to cause harmful gas hazards, even in severe cases even shed vegetables overnight withered, so should pay special attention to prevention. Harmful gases in the greenhouse, first of all due to improper fertilization technology, especially in the nitrogen fertilizer, large amount, or dry top dressing, the most likely to produce harmful gases, in addition, the application of a large number of fresh stables