Soil Surface Evaporation and Water Table Depths

Abstract

The experiment was conducted in lysimeters for studying the evaporation from soil surface in relation to water table depth and standard pan evaporation. Dummy variables 1 and 0 were used as an alternative to analyze the variance and covariance to compare the soil surface evaporation difference between water table depths. The dummy variable regression analysis can simultaneously test the difference between two regression lines whether due to slope coefficients or intercept terms. The water table depth was significantly affected on the soil surface evaporation. The soil surface evaporation for 38 cm water table was significantly smaller value than that for the 8 cm water table. The soil surface evaporation in wet season had a smaller deviation from the standard pan evaporation and had a more homogeneous distribution within the wet season than that in the dry season.