不同覆盖层次塑料大棚内温度和光照度的变化

Variation of Temperature and Illumination in Different-Layer Plastic Covered Tunnel Greenhouse

为了推进蔬菜的模式化栽培,对不同覆盖层次塑料大棚的内外温度和光照度进行了观测、分析.结果表明:棚内旬平均温度高于棚外.测定期内,单层覆盖塑料大棚的棚内平均气温变幅为5.6～21.0℃,棚内外最高温度差值的最大值为9.0℃;双层覆盖塑料大棚的棚内平均气温变幅为7.5～23.0℃,棚内外最高温度差值的最大值为10.5℃.双层覆盖塑料大棚的棚内气温和地温比单层覆盖塑料大棚分别高1.9～2.0℃和2.0～2.7℃.不同覆盖层次塑料大棚的棚内外平均气温差值以晴天最大,雨天次之,阴天最小;地温变化幅度小于气温;棚内外光照度都是在每天14:00时最强,且双层覆盖塑料大棚内的光照度总是小于单层覆盖塑料大棚.

To extend the cultivation model of vegetable,the law of microclimate variation in different-layer-plastic covered tunnel greenhouse in Changsha was probed into.The result showed that the average temperature every ten days in plastic-covered tunnel greenhouse was higher than that outside,ranging from 5.6 ℃ to 21.0 ℃ in single-layer plastic covered tunnel greenhouse,and the maximium amplitude of the highest temperature reached 9.0 ℃;while in double-layer plastic -covered greenhouse,the maximium amplitude of the highest temperature reached 10.5 ℃; ranging from 7.5 ℃ to 23.0 ℃;and the temperature of air and soil in double-layer plastic-covered tunnel greenhouse was higher than that of single- layer plastic-covered tunnel greenhouse.The difference of average temperature between inside and outside of different layer plastic-covered tunnel greenhouse reached the biggest in a fine day,smaller in a rainy day,and smallest in a cloudy day.The variation of soil temperature was smaller than that of air temperature.Illumination was the highest at 14:00 both inside and outside of the different layer plastic-covered tunnel greenhouse,and the illumination of double-layer plastic -covered tunnel greenhouse was less strong than that of single layer plastic-covered tunnel greenhouse.