地膜棉出苗后需要破膜放苗。出苗期如遇高温天气,放苗时间和方法不当,往往会造成烫苗,影响一播全苗。为了探讨和验证地膜棉烫苗温度与放苗标准,我们于1984年对膜内外温度变化规律进行了观察,1985年放苗时又进行了烫苗观察和小面积的放苗试验。兹将结果报道如下。 一、烫苗的膜内温度与大气日平均温度 1.出现烫苗与膜内温度有关。膜内日极端高温超过40℃有烫苗的危险,出现烫苗的概率为78％。但有时膜内日极端高温超过40℃,并来引起烫苗,其原因是烫苗不完全由于瞬时高温的作用,还由于热量的积累。如1985年4月16日和17日虽然日极端高温分别达45℃和48℃,但它是第一次出现在初期阶段,无长期热量积累,加之当天高温作用 After the emergence of plastic film need to rupture membrane Fangmiao. In case of hot weather in the emergence of seedlings, Fangmiao time and improper methods, often result in hot seedlings, affecting a broadcast seedlings. In order to explore and verify the cotton seedling temperature and standard seedling, we in 1984 on the film inside and outside the temperature changes were observed in 1985 when the seedling and then conducted a hot seedling observation and small area of ​​the seedling test. The results are reported below. First, the membrane temperature of hot seedlings and the average daily temperature of the atmosphere 1. There is a hot seedlings and membrane temperature. Extremes of high temperature within the membrane over 40 ℃ there is the risk of scalding, the probability of emergence of scald is 78%. But sometimes the extreme high temperature in the film over 40 ℃, and to cause hot seedlings, the reason is that the hot seedlings are not completely due to the role of instantaneous high temperature, but also due to heat accumulation. For example, on April 16 and 17, 1985, extreme high temperatures reached 45 ° C and 48 ° C respectively, but it was the first time that there was no long-term heat accumulation and the same day high temperature