蔬菜大棚内保持适宜的湿度是保证蔬菜正常生长发育的必要条件之一。在生产中，常用以调节湿度的方法主要有： 　　一、通过改变棚内温度来改变棚内湿度。一般棚内相对湿度为 100％，棚内温度为 5℃时，每升高 1℃，湿度下降 3％～ 4％，升高到 20℃时，湿度约为 70％，温度升 Vegetable greenhouse to maintain proper humidity is to ensure the normal growth and development of vegetables one of the necessary conditions. In production, commonly used to adjust the humidity are: First, by changing the shed temperature to change shed humidity. Generally, when the relative humidity in the shed is 100% and the temperature in the shed is 5 ℃, the humidity will drop by 3% ~ 4% for each increase of 1 ℃. When the temperature rises to 20 ℃, the humidity will be about 70%