日光温室番茄植株体温与气温差异研究

Difference between the tomato plant temperature and air temperatures in the solar greenhouse

植物群体间隙的空气温度不能准确地反映植物体实际的温度。该文用热电偶测定了日光温室内番茄茎、叶、果实的温度与同高度空气温度的差异。结果表明,日光温室番茄植株体温与同高度空气温度有明显的差异。不同部位二者差异不同。果实与空气温度差异最大,其次是茎、叶。这样环境温度测定后,结合植物体温与气温差异便可知植物体温。对番茄叶片测定了热时间常数,其均值为174 s,绝对偏差为73.1 s。热时间常数的测定,间接测定了综合热阻项,这为较难测定的植物表面传热热阻找到了一种易于得到的方式。

The temperature difference between the stem, leaf, fruit of tomato and the air at the same height was measured using the thermocouple temperature instrument, and the heat time constant of the tomato leaf was calculated. The result shows that the difference was clear, which was different at different parts of the plant. Fruit had the biggest temperature difference with the air at the same height whereas stem and leaf had the lower difference. The heat time constant of the tomato leaf was 172 s, whereas the absolute deflection is 73.1 s. The heat time constant is valuable because it is easier to be measured than the heat resistance and the general heat resistance can be obtained through its measurement.