Evapotranspiration of soil-plant-atmospheric continuum - a simulation study with lysimeter

Evapotranspiration (ET) and evaporation from ground water surface (Eg) are the two factors most difficult to determine in all components of field water balance. In regions with shallow ground water, the ground water plays an obvious role on supplying the soil water in unsaturated zone by capillary rise, which is of significant importance to the crop growth. The experimental data of water balance components and relevant parameters of soil-plant-atmospheric continuum model were obtained by lysimeter, Bowen ratio meter, hydraulic evapotranspirometer, etc. Based on the data measured by lysimeter, the simulation value of soil-plant-atmospheric continuum model was verified. The observed data of ET and Eg were comparatively analyzed with their simulation data, and the causes of difference between them were discussed.