산림 사면에서 토양수분 실측 자료, 평형증발 및 에디-공분산방법을 이용한 토양증발비교

Abstract

We compared equilibrium evaporation(<TEX>$E_{equili}$</TEX>) eddy-covariance(<TEX>$E_{eddy}$</TEX>) with soil moisture data(<TEX>$E_{SMseries}$</TEX>) 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 <TEX>$E_{eddy}$</TEX>, <TEX>$E_{equili}$</TEX> for the study period were estimated as 2.52, 3.28 mm and those of <TEX>$E_{SMseries}$</TEX> 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 <TEX>$E_{equili}$</TEX> 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.