INVESTIGATING VEGETATION-ATMOSPHERE WATER EXCHANGE BY USING HIGH FREQUENCY SPECTROSCOPY VAPOR ISOTOPE OBSERVATIONS

• WEI Zhongwang

  AORI, The University of Tokyo

• OKAZAKI Atsushi

  AORI, The University of Tokyo

• MAEDA Hidetoshi

  IEI, The University of Tokyo

• SATOH Yusuke

  AORI, The University of Tokyo

• KIGUCHI Masashi

  IIS, The University of Tokyo

• NODA Keigo

  IIS, The University of Tokyo

• KOIKE Masahiro

  Hosei University

• KIM Wonsik

  NIAES

• LIU Zhongfang

  The University of Tokyo

• YOSHIMURA Kei

  AORI, The University of Tokyo

Abstract

In this study, we first time test the feasibility of partitioning evapotranspiration using high frequency in-situ measurements of water vapor isotopes in a paddy field, Mase, Japan. By combining isotope measurements with Keeling plot method and Craig-Gordon model, transpiration is found representing more than 90% of the total evapotranspiration flux at the daily scale. However, the errors in this method could not be neglected. The primary cause of these errors is demonstrated to be the underestimate of water evaporation estimated by Craig-Gordon model. The variation of measured water vapor d-excess is significantly affected by the dominant components of evapotranspiration on diurnal time scale, it is suggested that the vegetation play a significant role in land surface water exchange process.

Journal

• Journal of Japan Society of Civil Engineers, Ser. B1 (Hydraulic Engineering)

  Journal of Japan Society of Civil Engineers, Ser. B1 (Hydraulic Engineering) 70 (4), I_181-I_186, 2014

  Japan Society of Civil Engineers

Keywords

• Stable water isotopes
• high-frequency laser spectrometer
• transpiration fraction
• d-excess

Details

• CRID: 1390282680329419520
• NII Article ID: 130005070165
• DOI: 10.2208/jscejhe.70.i_181
• ISSN: 2185467X
• Text Lang: ja
• Data Source:
  • JaLC
  • Crossref
  • CiNii Articles
• Abstract License Flag: Disallowed