한국농림기상학회지, 제 11권 제4호(2009) (pISSN 1229-5671, eISSN 2288-1859)
Korean Journal of Agricultural and Forest Meteorology, Vol. 11, No. 4, (2009), pp. 233~246
DOI: 10.5532/KJAFM.2009.11.4.233
ⓒ Author(s) 2014. CC Attribution 3.0 License.


광릉 활엽수림과 침엽수림에서 에디공분산으로
관측한 하부 군락의 증발산

강민석(1), 권효정(1), 임종환(2), 김 준(1,3)
(1)연세대학교 대기과학과/지구환경연구소, (2)국립산립과학원 산림보전부,
(3)동경대학교 GCOE 지속가능한 도시재생센터/산업과학연구소

(2009년 12월 10일 접수; 2009년 12월 30일 수정; 2009년 12월 30일 수락)

Understory Evapotranspiration Measured by Eddy-Covariance
in Gwangneung Deciduous and Coniferous Forests

Minseok Kang(1), Hyojung Kwon(1), Jong-Hwan Lim(2), Joon Kim(1,3)
(1)Global Environment Laboratory & Department of Atmospheric Sciences, Yonsei University, Seoul 120-749, Korea
(2)Division of Forest Conservation, Korea Forest Research Institute, Seoul 130-712, Korea
(3)Global Center of Excellence for Sustainable Urban Regeneration & Institute of Industrial Science,
The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656 Japan

(Received December 10, 2009; Revised December 30, 2009; Accepted December 30, 2009)

ABSTRACT
The partitioning of evapotranspiration (ET) into evaporation (E) and transpiration (T) is critical in understanding the water cycle and the couplings between the cycles of energy, water, and carbon. In forests, the total ET measured above the canopy consists of T from both overstory and understory vegetation, and E from soil and the intercepted precipitation. To quantify their relative contributions, we have measured ET from the floors of deciduous and coniferous forests in Gwangneung using eddy covariance technique from 1 June 2008 to 31 May 2009. Due to smaller eddies that contribute to turbulent transfer near the ground, we performed a spectrum analysis and found that the errors associated with sensor separation were <10%. The annual sum of the understory ET was 59 mm (16% of total ET) in the deciduous forest and 43 mm (~7%) in the coniferous forest. Overall, the understory ET was not negligible except during the summer season when the plant area index was near its maximum. In both forest canopies, the decoupling factor (Ω) was about ~0.15, indicating that the understory ET was controlled mainly by vapor pressure deficit and soil moisture content. The differences in the understory ET between the two forest canopies were due to different environmental conditions within the canopies, particularly the contrasting air humidity and soil water content. The non-negligible understory ET in the Gwangneung forests suggests that the dual source or multi-level models are required for the interpretation and modeling of surface exchange of mass and energy in these forests.

Keyword: Evapotranspiration, Understory, Eddy-Covariance, Decoupling factor, Coniferous forest, Deciduous forest

MAIN

적요

증발산(ET)을 증발(E)과 증산(T)으로 배분하는 것은 물 순환과 에너지, 물 및 탄소 순환의 연결고리를 이해하는 데에 매우 중요하다. 산림 군락의 총 증발산은 상부 및 하부 군락의 증산과 토양 및 차단 강수로부터의 증발로 구성된다. 이들의 상대적 기여도를 정량화하기 위해, 에디 공분산 방법을 사용하여 2008년 6월 1일부터 2009년 5월 31일까지 광릉 활엽수림과 침엽수림의 마루에서의 증발산을 관측하였다. 스펙트럼 분석에 따르면, 초음파 풍향 풍속계와 수증기 농도측정기 사이의 거리에 의한 증발산 과소 평가는 군락하부에서 연간 증발산량의 약 10%정도였다. 하부군락의 연간 증발산은 활엽수림과 침엽수림에서 각각 59mm와 43mm로, 총 증발산량의 16%와 7%를 차지하였다. 전반적으로 식생면적지수가 최대인 여름 기간을 제외하고는 하부군락의 증발산은 총 증발산에서 무시할 수 없는 부분을 차지하였다. 두 산림지역의 비결합 모수(Ω)는 약 0.15이었으며, 이는 하부군락의 증발산이 주로 포차나 토양 수분에 의해서 조절됨을 보여준다. 두 산림의 하부 군락의 증발산의 차이는 군락하부의 환경 조건의 차이에 기인하며, 특히 습도와 토양 수분의 차이로 인해 발생하였다. 광릉 하부 군락의 증발산 기여도가 작지 않다는 사실은 이러한 산림의 물질과 에너지 플럭스를 해석하고 모델링하기 위해서는 이원 또는 다층 모형이 필요함을 시사한다.

REFERENCES

Baldocchi, D. D., C. A. Vogel, and B. Hall 1997: Seasonal variation of energy and water vapor exchange rates above and below a boreal jack pine forest canopy, Journal of Geophysical Research 102(D24), 28,939-28,951

Baldocchi, D. D., B. E. Law, and P. M. Anthoni, 2000: On measuring and modeling energy fluxes above the floor of a homogeneous and heterogeneous conifer forest, Agricultural and Forest Meteorology 102(2-3), 187-206crossref(new window)

Baldocchi, D. D., L. Xu, and N. Kiang, 2004: How plant functional-type, weather, seasonal drought, and soil physical properties alter water and energy fluxes of an oak-grass savanna and an annual grassland, Agricultural and Forest Meteorology 123(1-2), 13-39crossref(new window)

Br$\acute{e}$da, N. J. J., 2003: Ground-based measurements of leaf area index: a review of methods, instruments and current controversies, Journal of Experimental Botany 54, 2403-2417crossref(new window)

Denmead O.T., 1984: Plant physiological methods for studying evaporation: Problems of telling the forest from the trees, Agricultural Water Management 8(1-3), 167-189crossref(new window)

Hong, J., J. Kim, D. Lee, and J.-H. Lim, 2008: Estimation of the storage and advection effects on H2O and CO2 exchanges in a hliily KoFlux forest catchment, Water Resources Research 44, W01426crossref(new window)

Hong, J., H. Kwon, J.-H. Lim, Y,-H. Byun, J. Lee, and J. Kim, 2009: Standardization of KoFlux Eddy-Covariance Data Processing, Korean Journal of Agricultural and Forest Meteorology 11(1), 19-26 (in Korean with Englishabstract)

Iida, S. i., T. Ohta, K. Matsumoto, T. Nakai, T. Kuwada, A. V. Kononov, T. C. Maximov, M. K. van der Molen, H. Dolman, H. Tanaka, and H. Yabuki, 2009: Evapotranspiration from understory vegetation in an eastern Siberian boreal larch forest, Agricultural and Forest Meteorology149(6-7), 1129-1139crossref(new window)

Jang, K., S. Kang, H. Kim, and H. Kwon, 2009: Evaluation of shortwave irradiance and evapotranspiration derived from Moderate Resolution Imaging Spectroradiometer(MODIS), Asia-Pacific Journal of Atmospheric Sciences 45(2), 233-246

Kang, M., S. Park, H. Kwon, H. T. Choi, Y.-J. Choi, and J. Kim, 2009: Evapotranspiration from a deciduous forest in a complex terrain and a heterogeneous farmland under monsoon Climate, Asia-Pacific Journal of Atmospheric Sciences 45(2), 175-191

Kim, J., D. Lee, J. Hong, S. Kang, S.-J. Kim, S.-K. Moon,J.-H. Lim, Y. Son, J. Lee, S. Kim, N. Woo, K. Kim, B.Lee, B.-L. Lee, and S. Kim, 2006: HydroKorea and CarboKorea: cross-scale studies of ecohydrology and biogeochemistry in a heterogeneous and complex forest catchment of Korea, Ecological Research 21(6), 881-889crossref(new window)

Kwon, H., T.-Y. Park, J. Hong, J.-H. Lim, and J. Kim,2009: Seasonality of net ecosystem carbon exchange in two major plant functional types in Korea, Asia-Pacific Journal of Atmospheric Sciences 45(2), 149-163

Lee, Y.-H. and H.-J. Lim, 2009: Evaluation of modified Soil-Plant-Atmosphere Model (mSPA) to simulate net ecosystem carbon exchange over a deciduous forest at Gwangneung in 2006, Korean Journal of Agricultural and Forest Meteorology 11(3), 87-99

Massman, W. J., 2000: A simple method for estimating frequency response corrections for eddy covariance systems, Agricultural and Forest Meteorology 104(3), 185-198crossref(new window)

McNaughton, K. G. and P, G, Jarvis, 1983: Predicting Effects of Vegetation Changes on Transpiration and Evaporation, Water Deficits and Plant Growth Vol. VII,pp. 1-47

Monteith, J. L., 1965: Evaporation and Environment, In The State and Movement of water in living Organisms, Symposium of the Society for Experimental Biology, Academic Press, NY, 205-234

Moore, C. J., 1986: Frequency response corrections for eddy correlation systems, Boundary-Layer Meteorology37(1), 17-35crossref(new window)

Raupach, M, 2001: Combination theory and equilibrium evaporation, Quarterly Journal of Royal Meteorology Society 127, 1149-1181crossref(new window)

Scott, R. L., C. Watts, J. G. Payan, E. Edwards, D. C. Goodrich, D. Williams, and W. James Shuttleworth, 2003: The understory and overstory partitioning of energy and water fluxes in an open canopy, semiarid woodland, Agricultural and Forest Meteorology 114(3-4), 127-139crossref(new window)

Tanner, B.D., Swiatek, E., Greene, J. P., 1993: Density fluctuation and use of krypton hygrometer in Surface flux measurements, Proceeding of the Conference on Management of Irrigation and Drainage Systems, Park city, UT, 945-952

Webb, E. K., G. I. Pearman, and R. Leuning, 1980: Correction of flux measurements for density effects due to heat and water vapor transfer, Quarterly Journal of Royal Meteorology Society 106, 85-100crossref(new window)

Wilczak, J., S. Oncley, and S. Stage, 2001: Sonic Anemometer Tilt Correction Algorithms, Boundary-Layer Meteorology99(1), 127-150crossref(new window)

Wilson, K. B. and T. P. Meyers, 2001: The Spatial variability of energy and carbon dioxide fluxes at the floor of a deciduous Forest, Boundary-Layer Meteorology 98(3), 443-473crossref(new window)