夏玉米棵间土面蒸发与蒸发蒸腾比例研究

Ratio of soil evaporation to the evapotranspiration for summer maize field

利用连续4年的大型称重式蒸渗仪和小型棵间蒸发器的测定资料,研究了不同灌溉定额条件下夏玉米生长期间的逐日蒸发蒸腾和棵间蒸发过程。结果表明,夏玉米总的蒸发蒸腾量在年际间变化较大,其中叶面蒸腾总量变化较大,在158.44-233.99 mm;棵间蒸发总量变化较小,在171.43-181.52 mm,棵间蒸发量占蒸发蒸腾量的比例(E/ET)在43.57%-52.52%之间。降水和灌溉以及气象因素对夏玉米生育期棵间蒸发的影响较小,而对叶面蒸腾的影响较大。得出充分灌溉和非充分灌溉条件下,棵间蒸发占蒸发蒸腾的比例与叶面积指数的相关系数分别达到0.85和0.77以上。

A large weighing lysimeter and micro-lysimeters were used to measure the process of evapotranspiration and soil evaporation during four growing seasons of summer maize under different irrigation shedules. The results showed that the change of total evapotranspiration was large among years, among which the change of total transpiration is larger, the range of transpiration changes from 158. 44 mm to 233.99mm; The soil evaporation changing is small, the range of soil evaporation changes from 171. 43 mm to 181. 52 ram. The ratio of soil evaporation to the evapotranspiration changes from 43.57% to 52.52%. The effects of rain, irrigate and weather condition on the soil evaporation of summer maize in growth period are insignificant, but their effects on the transpiration are significant. Under sufficientand unsufficient irrigation condition, the related coefficients between the ratio of E to ET and LAI are above 0.85 and 0.77 .