甘肃武山多层覆盖塑料大棚冬季保温效果研究

摘要

多层覆盖是甘肃渭河流域冬季塑料大棚保温的一个重要手段,本试验通过在塑料大棚内搭建不同小棚并覆盖塑料薄膜,对塑料大棚多层覆盖的冬季保温效果进行了研究.结果表明,塑料大棚多层覆盖可以提高棚内气温和地温,随着覆盖层数的增多棚内气温的升高幅度降低.每增加1层棚膜,棚内日最低温度提高1.84~4.48℃,日平均温度提高1.38~3.72℃.采用4层覆盖,棚内日最低温度可提高5.69℃,平均温度提高13℃左右;单层覆盖时会出现逆温现象.不同覆盖层棚内温度与外界气温间关系密切,随着保温层数的增多,棚内温度受外界气温的影响越来越小.%Multi-layer cover is an important way for heat preservation in plastic tunnel in winter at the Wei River basin.This experiment studied the heat preservation effect in winter under plastic tunnel with multi-layer plastic film by constructing small size shed covered with plastic film inside of the big plastic tunnel.The results showed that the air temperature and soil temperature inside of plastic tunnel were all raised by covering multi-layer plastic film,but the ascending range of air temperature was reduced along with the increasing of covering layers. The greenhouse film mulch had salient warming effect.The daily minimum temperature within the tunnel increased by 1.84-4.48 ℃,and daily mean temperature increased by 1.38-3.72 ℃ when increasing the numbers of layer. The daily minimum temperature could be increased to 5.69 ℃,and average temperature increased about 13 ℃ by 4 mulch layers.Temperature inversion appeared only under one layer of plastic film.There is very close relation between inside tunnel temperature and outside tunnel temperature with different covering layers.The increasing layer numbers can reduce the influence of outside tunnel temperature on inside tunnel temperature.