Comparison of Soil Evaporation Using Equilibrium Evaporation, Eddy-Covariance and Surface Soil Moisture on the Forest Hillslope

Title & Authors
Comparison of Soil Evaporation Using Equilibrium Evaporation, Eddy-Covariance and Surface Soil Moisture on the Forest Hillslope
Gwak, Yong-Seok; Kim, Sang-Hyun; Kim, Su-Jin;

Abstract
We compared equilibrium evaporation($\small{E_{equili}}$) eddy-covariance($\small{E_{eddy}}$) with soil moisture data($\small{E_{SMseries}}$) which were measured with a 2 hours sampling interval at three points for a humid forest hillslope from May 5th to May 31th in 2009. Accumulations of $\small{E_{eddy}}$, $\small{E_{equili}}$ for the study period were estimated as 2.52, 3.28 mm and those of $\small{E_{SMseries}}$ were ranged from 1.91 to 2.88 mm. It suggested that the eddy-covariance method considering the spatial heterogeneity of soil evaporation is useful to evaluate the soil evaporation. Method A, B and C were proposed using mean meterological data and daily moisture variation and the computations were compared to eddy-covariance method and equilibrium evaporation. The methods using soil moisture data can describe the variations of soil evaporation from eddy-covariance through simple moving average analysis. Method B showed a good matched with eddy-covariance method. This indicated that Dry Surface Layer (DSL) at 14:00 which was used for method B is important variable for the evaluation of soil evaporation. The total equilibrium evaporation was not significantly different to those of the others. However, equilibrium evaporation showed a problem in estimating soil evaporation because the temporal tendency of $\small{E_{equili}}$ was not related with the those of the other methods. The improved understanding of the soil evaporation presented in this study will contribute to the understandings of water cycles in a forest hillslope.
Keywords
Soil moisture;Soil evaporation;Equilibrium evaporation;Forested hillslope;
Language
Korean
Cited by
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