用Micro-Lysimeters和大型蒸渗仪测定夏玉米蒸散的研究

Determination of daily evaporation and evaportranspiration of summer corn fields by Large-scale Lysimeter and Micro-Lysimeters

利用大型称重式蒸渗仪和自制的Micro-Lysimeters对夏玉米生育期的蒸散量进行了研究。研究发现夏玉米整个生育期的棵间蒸发占总蒸散量的36.01%,其中大部分集中在生育前期;不同深度层次的土壤水分和棵间蒸发与蒸散量的比例(E/ETwd)随着深度的增加相关性越来越弱,10cm土壤含水量与E/ETwd的相关系数R2=81.23%,30cm土壤含水量与E/ETwd的相关系数R2=46.47%,50cm土壤含水量与E/ETwd的相关系数R2=34.09%;叶面积指数与E/ETwd也有密切的关系,相关系数R2=87.47%。

Experiments have been conducted to determine the daily alteration processes of evaportranspiration and soil evaporation of summer corn during growing period by using largescale weighing lysimeter and microlysimeter. According to the observation data, about 36.01% of the total field evapotranspiration is consumed by the soil evaporation, most of which is concentrated in the early growing period. The relationship between E/ETwd and the soil water content of different depth and the that between E/ETwd and leaf area index are analyzed. The results show that the correlation coefficients (R2) between E/ETwd and soil water content at 10 cm, 30 cm and 50 cm, are 81.23%, 46.47% and 34.09% respectively, and the correlation coefficient (R2) between E/ETwd and LAI is 87.47%.\;