TGF: Terrestrial Environment Research Center,  
University of Tsukuba

General site detail (updated 11 April 2008)
 Site name
 Terrestrial Environment Research Center, 
 University of Tsukuba
 AsiaFlux site code
 Location Tsukuba, Ibaraki, Japan
 Position 36º 07'N, 140º 08'E
 Elevation 20 m above sea level 
 Slope Nearly 0 deg.
 Terrain type
 Almost flat
 Area 20,000 m2
 Fetch 150 m (for main wind direction)
 Climate Warm and humid climate
 Mean annual air temperature
 14.1 ºC (2001-2003)
 Mean annual precipitation
 1157 mm (2001-2003)
 Vegetation type
 C3/C4 grassland
 Domestic species (Overstory)
 Solidago altissima Linn.
 Miscanthus sinensis Andress.
 Imperata cylindrical Beauv. Var. koenigii Durand et  Schinz
 Dominant species (Understory)
 Canopy height
 Varied from zero to 1.8 m
 Age Annual herb
 LAI -
 Soil type
 Kuroboku soil

Eddy Covariance method (CO2)
 System Open-path system  (CO2 flux, latent heat flux)
 Wind speed 
 Sonic anemometer-thermometer, DA600-3T (KAIJO)
 Air temperature
 Water vapor
 Open path(LI-7500, Li-Cor, USA)
 CO2 Open path(LI-7500, Li-Cor, USA)
 Measurement height
 2.0 m 
 Sampling frequency
 10 Hz
 Averaging time
 30 min
 Data logger
 CR-23x  (Campbell, USA)
 Data storage
 Original data
 Raw data and statistics

 Observation items
  Levels/ Depth
 Global solar radiation(incoming)
 2.4 m Radiometer MR-40 (Eko)
 Global solar 
radiation (outgoing)
 2.4 m Radiometer MR-40 (Eko)
 Long-wave radiation(incoming) 
 2.4 m Radiometer MR-40 (Eko)
  Long-wave radiation(outgoing) 2.4 m Radiometer MR-40 (Eko)
 Net radiation
 2.4 m Radiometer MR-40 (Eko)
 PPFD (incoming)
 2.4 m Quantum sensor, IKS-27 (Koito)
 PPFD (outgoing)
 Direct / diffuse radiation
 Direct / diffuse PPFD
 Air temperature
 2.0 m Platinum resistance thermometer, HMP45A  (Vaisala)
 Humidity 2.0 m Capacitive moisture sensor, HMP45A (Vaisala)
 Soil temperature
 0.05 m T-type thermocouple (handmade)
 Soil heat flux
 0.05 m Heat plate, MF-81 (Eko)
 Soil water 
 0.15 m CS615 (Vaisala)
 Wind speed
 2.0 m Sonic anemometer-thermometer, DAT600  (KAIJO)
 Wind direction
 Precipitation - TERC* routine
 (*TERC: Terrestrial Environment Research  Center,  University of Tsukuba)
 H2O concentration - 
 Soil respiration
 Photosynthesis porometer LI-6400R
 Photosynthesis Photosynthesis porometer LI-6400 (Li-cor)
 Ecological investigation
 Monthly (from Apr to Oct)
Observation Period and Data Availability
 Measurement Period
 from 2001-2004
 Measurement Frequency
 Data Availability
 Jun Asanuma (asanuma [at]
 Terrestrial Environment Research CenterUniversity of Tsukuba Tsukuba,  Ibaraki 305-8577, Japan
 Tel:+81-298-53-6704 Fax:+ 81-298-53-6704
 Seiji Shimoda (sss [at]
 National Agricultural Research Center for Western Region 6-12-1 
 Nishi-fukatsucho, Fukuyama, Hiroshima, 721-8514 Japan.
 Tel:+849-23-5342(ex.660) Fax:+81-849-24-7893
 Yohei Hamada (hamada [at]
 Graduate School of Life and Environmental Sciences, 
  University of Tsukuba 
 1-1-1 Tennodai, Tsukuba, Ibaraki, 305-8572 Japan
 TEL:029-853-4531 FAX:029-853-6614
 Takehisa Oikawa
 Calibration Information
 Open-path analyzers were calibrated approximately every one to two  months with standard CO2 gases and a dew point generator (LI610; LI-  COR Inc., USA)
 AV 100 V