喷灌条件下冬小麦冠层温度的试验研究

Canopy temperature of winter wheat in sprinkle irrigation

研究了喷灌条件下冬小麦冠层温度在不同土壤水分条件下的变化规律及其随作物生长发育期的变化状况。结果表明,在喷灌条件下,冠层温度的变化规律同普通灌溉的变化规律基本相同。当灌水量达一定程度后,冠层温度不再下降,反而呈现上升趋势;土壤水分对冠层温度的影响程度相对减小,不为主要决定因子;对于冬小麦,当灌溉量增加到一定程度时,反而不利于冬小麦的生长,水分利用效率也下降,在灌足底墒水和返青、拔节期均灌溉的情况下,小麦生长期间每次灌水量不宜过大,以每次灌水量不超过300m3/hm2为宜。

The experiment was conducted to study the canopy temperatures and the growth of winter wheat at different moistures in sprinkle irrigation. The results showed that the canopy temperature in sprinkle irrigation varied generally in the same manner as that in conventional irrigation did. When the irrigation water reached a certain amount, the canopy temperature tended to rise instead of continuing to decline and the soil moisture had a relatively weakened effect on the canopy temperature so as not to be a major decisive factor; meantime, when the irrigation water reached a certain amount, it would negatively affect the growth of winter wheat and lowered the water use efficiency. Where wheat had sufficient soil moisture before sowing and were irrigated at re-greening and jointing stages, respectively, the amount of irrigation water should not be too high during wheat growth and it was not advisable for the amount of water for each irrigation to surpass 300 m^3/hm^2.