HCH: Hachihama Experimental Farm

General site detail (updated 30 June 2011)
 Site name
 Hachihama Experimental Farm
 AsiaFlux site code
 Location Tamano City, Okayama Prefecture
 Position 34º 32’ N, 133º 56' E
 Elevation -2 m ASL
 Slope -
 Terrain type
 Area About 300 ha (3km by 1km along kamo-river)
 Fetch About 200 m (all wind directions)
 Climate Warm and humid climate
 Mean annual air temperature
 16.7 ºC
 Mean annual precipitation
 1100 mm 
 Vegetation type
 Rice paddy Field
 Domestic species (Overstory)
 Rice ( Olyza sativa L.; cultivar Akebono )
 Dominant species (Understory)
 Canopy height
 About 1.2 m (maximum)
 Age N/A
 LAI About 4.5 m2 m-2 (maximum)
 Soil type
 Strong gley lowland soils (Classification of  cultivated soils in Japan, 1996)

Eddy Covariance method (CO2)
 System Open-path system 
 Wind speed 
 Sonic anemometer-thermometer, DA600 (SONIC)
 Air temperature
 Sonic anemometer-thermometer, DA600 (SONIC)
 Water vapor
 Before June, 2003: E009B (Advanet) , 
 After July, 2003: Li7500 (Li-Cor)
 CO2 Before June, 2003: E009B (Advanet) , 
 After July, 2003: Li7500 (Li-Cor)
 Measurement height
 1.8 m
 Sampling frequency
 10 Hz
 Averaging time
 30 min
 Data logger
 Laptop PC based system with DAQ700 card
 (National Instruments Co.)
 Data storage
 HDD on PC, mobile HDD, and Database server
 Original data
 Raw data

 Observation items
  Levels/ Depth
 Global solar radiation(incoming)
 2 m MR-40 (Eiko, Japan)
 Global solar 
radiation (outgoing)
 2 m MR-40 (Eiko, Japan)
 Long-wave radiation(incoming) 
 2 m MR-40 (Eiko, Japan)
  Long-wave radiation(outgoing) 2 m MR-40 (Eiko, Japan)
 Net radiation
 2 m MR-40 (Eiko, Japan)
 PPFD (incoming)
 PPFD (outgoing)
 Direct / diffuse radiation
 Direct / diffuse PPFD
 Air temperature
 1.5 m HMP45A (Vaisala)
 Humidity 1.5 m 
 HMP45A (Vaisala)
 Soil temperature
 0.2 m 
 Platinum resistance thermometer (N/A)
 Soil heat flux
 0.01 m 
 MF180 (EKO, Japan)
 Soil water 
 0.03 m
 5TM, Decagon
 Wind speed
 1.8 m 
 sonic anemometer thermometer 
 ( DA600, KAIJO, Japan)
 Wind direction
 1.8 m sonic anemometer thermometer 
 ( DA600, KAIJO, Japan)
 1.0 m PTB210, Vaisala
 Precipitation 0.6 m Rain Guage, OTA
 1.8 m CO2/H2O analyzer (LI-7500 LI-COR, USA)
 H2 concentration 1.8 m CO2/H2O analyzer (LI-7500 LI-COR, USA)
 Soil respiration
 Photosynthesis -
 Ecological investigation
Observation Period and data Availability
 Measurement Period
 From December 1998 to present
 Measurement Frequency
 Data Availability
 Toru Iwata (iwata [at] cc.okayama-u.ac.jp)
 Takeshi Miura (miurat [at] cc.okayama-u.ac.jp)
 Graduate school of Environmental Science, 
 Okayama University3-1-1, Tsushima-Naka, Kita-ku, Okayama-City,  Okayama, 700-8530, Japan
 Tel:+81-86-251-8846 Fax: +81-86-251-8866
  Reserch Fund
 B-3 project, GERF,
 JapanS-1 project, GERF
 JapanGlobal warming project, MAFF, Japan