HCH: Hachihama Experimental Farm
General site details
| Site name | Hachihama Experimental Farm |
|---|---|
| AsiaFlux site code | HCH |
| 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 |
| Dominant Species (Overstory) | Rice ( Olyza sativa L.; cultivar Akebono ) |
| Dominant Species (Understory) | N/A |
| 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) |
Observation
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 |
Meteorology
| Observation items | Levels/Depth | Instrument |
|---|---|---|
| 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 content | 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) |
| Barometric pressure | 1.0 m | PTB210, Vaisala |
| Precipitation | 0.6 m | Rain Guage, OTA |
| CO2 concentration | 1.8 m | CO2/H2O analyzer (LI-7500 LI-COR, USA) |
| H2O concentration | 1.8 m | CO2/H2O analyzer (LI-7500 LI-COR, USA) |
Other
| Soil respiration | - |
| Photosynthesis | - |
| Ecological investigation | - |
Observation Period and Data Availability
| Measurement Period | From December 1998 to present |
|---|---|
| Measurement Frequency | Continuous |
| Data Availability | N/A |
Contact
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
Research Fund
B-3 project, GERF,
JapanS-1 project, GERF
JapanGlobal warming project, MAFF, Japan