YNF: Yona-Field Tower Site
General site details
| Site name | Yona-Field Tower Site |
|---|---|
| AsiaFlux site code | YNF |
| Location | Kunigami, Okinawa, Japan |
| Position | 26° 45' 3.5" N, 128° 12' 45.5" E |
| Elevation | 210 m above sea level |
| Slope | - |
| Terrain type | Ridge |
| Area | 0.25 ha (Tree survey plot) |
| Fetch | - |
| Climate | Humid Subtropical (Mild with no dry season, hot summer (Cfa)) |
| Mean annual air temperature | 20.7℃ (1981-2010) |
| Mean annual precipitation | 2501.5 mm (1981-2010) |
| Vegetation type | Evergreen broad leaf forest |
| Dominant Species (Overstory) | Castanopsis sieboldii, Rapanea neriifolia, llex liukiuensis, Schima wallichii |
| Dominant Species (Understory) | Dwarf bamboo (Pleioblastus linearis) and ferns |
| Canopy height | About 8 m |
| Age | More then 75 years old |
| LAI | 3.6 |
| Soil type | Haplic Acrisol (Ultisol) |
Observation
Eddy Covariance method (CO2)
| System | Open-path gas analyzer was calibrated approximately every year with standard gases and dew point generator (LI-610, LI-COR). |
|---|---|
| Wind speed | Integrated CO2 and H2O open-path gas analyzer and 3-D sonic anemometer (IRGASON, Campbell Scientific) |
| Air temperature | Integrated CO2 and H2O open-path gas analyzer and 3-D sonic anemometer (IRGASON, Campbell Scientific) |
| Water vapor | Integrated CO2 and H2O open-path gas analyzer and 3-D sonic anemometer (IRGASON, Campbell Scientific) |
| CO2 | Integrated CO2 and H2O open-path gas analyzer and 3-D sonic anemometer (IRGASON, Campbell Scientific) |
| Measurement height | 16 m |
| Sampling frequency | 30 min |
| Averaging time | 30 min |
| Data logger | CR1000 (Campbell Scientific) |
| Data storage | Flash memory |
| Original data | Raw data |
Meteorology
| Observation items | Levels/Depth | Instrument |
|---|---|---|
| Global solar radiation (incoming) | 15 m | 4-component net radiometer (NR01, Hukseflux) |
| Global solar radiation (outgoing) | 15 m | 4-component net radiometer (NR01, Hukseflux) |
| Long-wave radiation (outgoing) | 15 m | 4-component net radiometer (NR01, Hukseflux) |
| Net radiation | 15 m | 4-component net radiometer (NR01, Hukseflux) |
| PPFD (incoming) | 15, 1 (two points) m | Quantum Sensor (LI-190S, LI-COR; PAR-01D, Prede; MIJ-14,Environmental Measurement Japan) |
| PPFD (outgoing) | 15, 1 m | Quantum Sensor (PAR-01D, Prede) |
| Direct/diffuse radiation | - | - |
| Direct/diffuse PPFD | - | - |
| Air temperature | 16, 13, 10, 2 m | Forced ventilated air temperature and relative humidity sensor (HMP155D, Vaisala) |
| Humidity | 16, 13, 10, 2 m | Forced ventilated air temperature and relative humidity sensor (HMP155D, Vaisala) |
| Soil temerature | 0.05, 0.1, 0.2, 0.5, 0.8 m depth | Soil moisture and temperature sensor (CS650, Campbell Scientific) |
| Soil heat flux | 0.05 m (three points) | Heat flux plate (HFP01, Hukseflux) |
| Soil water content | 0.05, 0.1, 0.2, 0.5, 0.8 m depth | Soil moisture and temperature sensor (CS650, Campbell Scientific) |
| Wind speed | 16, 13, 10, 2 m | Wind direction sensor (010C, MetOne) |
| Wind direction | 16 m | 3-cup anemometer (020C, MetOne) |
| Barometric pressure | 15, 2 m | Barometer (PTB110, Vaisala) |
| Precipitation | 15.5, 1.5 (three points) m | 0.5-mm tipping backet rain gauge (OW-34-BP, Ota Keiki) |
| Soil water potential | 0.05, 0.1, 0.2, 0.5, 0.8 m depth | Tensiometer (CHR-TM, Climatec) |
| Spectral radiation (in and out) | 15 m | Spectroradiometer (MS700, Eko) |
Soil respiration
| Measurement method | Closed dynamic chamber method (manual measurements) |
| Reference(s) for method | - |
| Measuring system | LI-6400 (LI-COR) |
| IRGA | LI-6400 (LI-COR) |
| Flow control | - |
| Chamber type | Closed dynamic chamber |
| Chamber size | 95 cm internal diameter |
| Number of chambers | 50 |
| Measuring intervals | Uncontinuous; once or twice each month from Oct. 2013 to Dec. 2014 |
| In the ground covered by show in winter? | No |
| Original data | Raw data |
| Temperature and air pressure correction | No |
Other
| Photosynthesis | - |
| Ecological Investigation | Tree height, diameter, stand density (every 3 years) |
Observation Period and Data Availability
| Measurement Period | February 2013 to present |
|---|---|
| Measurement Frequency | Continuous |
| Data Availability | - |
Contact
Kazuho Matsumoto (kazuhom[at]iwate-u.ac.jp) Faculty of Agriculture, Iwate University 3-18-8 Ueda, Morioka, Iwate 020-8550, JAPAN Tel: +81-19-621-6161 Fax: +81-19-621-6161
Shingo Taniguchi (shingota[at]agr.u-ryukyu.ac.jp) Faculty of Agriculture, University of the Ryukyus 1 Senbaru, Nishihara, Okinawa 903-0213, JAPAN Tel: +81-98-895-8793 Fax: +81-98-895-8793
Atsushi Takashima (a-taka[at]agr.u-ryukyu.ac.jp) Yona Field, Subtropical Field Science Center, Faculty of Agriculture, University of the Ryukyus 685 Yona, Kunigami, Okinawa 905-1427, JAPAN Tel: +81-98-041-2242 Fax: +81-98-041-2189
Infrastructure
Tower, Electrical power (AC)
Research Fund
-
Calibration Information
Open-path gas analyzer was calibrated approximately every year with standard gases and dew point generator (LI-610, LI-COR).
Publication
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