蔬菜幼苗定植后,大棚两侧温度状况远不如大棚中间好,易受到霜冻的危害,可采取以下几项措施,加以解决: 一、掌握定植适期。应以大棚周围的土壤温度为标准,来制定定植适期。二、设小拱棚。对边行幼苗,在夜间覆盖临时性小拱棚,不用压土封严。三、设“天幕”。即夜间在大棚膜下用薄膜拉 Vegetable seedlings colonization, the temperature on both sides of the greenhouse far better than the middle of the greenhouse, vulnerable to the dangers of frost, can take the following measures to be addressed: First, grasp the planting period. Soil temperature should be around the greenhouse as a standard, to develop colonization appropriate period. Second, set a small shed. On the line of seedlings, covering the temporary small arch at night, without pressure seal. Third, set up a “sky screen.” That night under the greenhouse film with a film pull