Japanese larch (Larix Kaempferi Sarg.), evergreen needle-leafed species (Pinus densiflora and Abies homolepis), deciduous broad-leafed species (Swida controversa, Quercus serrata, Quercus crispula, Betula platyphylla var.japonica, Prunus incisa, etc.)
Dominant species (Understory)
Ferns (Dryopteris crassirhizoma, Dryopteris expansa), bamboo grass (Sasamorpha borealis), and other herbs.
Canopy height
20-26 m
Age
Around 70 years old (Planted around 1950)
LAI
Larch: 2.8 m2m-2 estimated based on the leaf mass abundance (Okano & Arase 2007), and 2.4 m2m-2 estimated based on 3D portable laser scanner measurement (Maki et al., 2012), Understory: 3.0 m2m-2 (max)
Soil type
Coarse volcanic ash (Urakawa et al., 2015)
Observations Eddy Covariance method (CO2)
System
Open- and closed-path systems (CO2 flux, latent heat flux)
Wind speed
Three-dimensional sonic anemometer-thermometers: DA-600-3TV, Probe TR-61C, SONIC CORP. (Jan.1, 2006- May 9, 2011), DA-650-3TV, Probe TR-61C, SONIC CORP. (May 9, 2011- Nov.22, 2011), DA-600-3TV, Probe TR-61C, SONIC CORP. (Nov.22, 2011- Apr.18, 2012), DA-700-3TV, Probe TR-61A, SONIC CORP. (Apr.18, 2012- Apr.11 2016)
Air temperature
Platinum resistance thermometer and capacitive hygrometer (HMP45A, Vaisala)
Hyperbolic relaxed eddy accumulation (HREA) method with a laser-based analyzer (GGA-24r-EP, Los GatosResearch Inc., USA), from Aug. 2011 to Sep. 2012 (Ueyama et al., 2013) Automated dynamic closed (non-steady-state through-flow) chambers with a laser-based analyzer (GGE-24r-EP), from Oct. 2012 (Ueyama et al., 2015)
Measurement height
35, 28, 18, 5, and 0.3m (HREA method), 0m (chambers)
Nobuko Saigusa (n.saigusa [at] nies.go.jp) Center for Global Environmental Research (CGER), National Institute for Environmental Studies (NIES) 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 JAPAN Tel : +81-29-850-2517 Fax : +81-29-858-2645 http://db.cger.nies.go.jp/gem/moni-e/warm/flux/fuji.html
[Flux and micrometeorology] Yoshiyuki Takahashi (yoshiyu [at] nies.go.jp) Center for Global Environmental Research (CGER), National Institute for Environmental Studies (NIES) 16-2 Onogawa, Tsukuba, Ibaraki 305-8506 JAPAN Tel : +81-29-850-2468 Fax : +81-29-858-2645
Automated dynamic closed chamber method (flow-through, non-steady-state design using IRGA and Integrated Cavity Output Spectroscopy (CH4/CO2))
References for method
Teramoto M., Liang N., Takahashi Y., Zeng J., Saigusa N., Ide R., Zhao X., 2019: Enhanced understory carbon flux components and robustness of net CO2 exchange after thinning in a larch forest in central Japan. Agricultural and Forest Meteorology, 274, 106-117. Teramoto M., Liang N., Zeng J., Saigusa N., Takahashi Y., 2017: Long- term chamber measurements reveal strong impacts of soil temperature on seasonal and inter-annual variation in understory CO2 fluxes in a Japanese larch (Larix kaempferi Sarg.) forest. Agricultural and Forest Meteorology, 247, 194-206.
Measuring system
A24-channel automated chamber system (home-made by the investigator)
IRGA Integrated Cavity Output Spectroscopy
Li-820 (LI-COR), UGGA (LGR)
Flow control
High-precision flow transducer (FSM-V, CKD) and manual flow regulator
Chamber type
Clear PVC chamber
Chamber size
92cm in length × 90cm in width × 50cm in height (8 chambers for soil respiration and 8 chambers for heterotrophic respiration), and 90cm in length × 90cm in width × 100cm in height (8 chambers for net understory CO2 exchange).
Number of chambers
24
Measuring intervals
The maesurement period, during which the chamber lids were closed, was 2.5min for each chamber (with data recorded at 10-s intervals using CR1000 datalogger (Campbell Scientific Inc.)) from 2006 to 2009. The meassurement period was 5.0min from 2010 on.
Is the ground covered by snow in winter, how about the measurement on winter?
Missing soil CO2 efflux data (gaps) during snow covered period were estimated based on Lloyd and Taylor equation for each chamber.
Original data
Raw data
Air temperature collection
Air temperature inside each chamber was measured using the home-made T-Type thermocouple.
Soil temperature collection
Soil temperature at the depth of 5-cm inside each chamber was measured using the home-made T-Type thermocouple.
Air pressure collection
Air pressure was measured using PX2760 (Omega Engineering)
Understory PPFD collection
6 sensors (SQ225; Apogee Instruments Inc.) at the height of 1m around plant chambers
Soil moisture collection
6 CS616 (Campbell Scientific Inc.) were used for monitoring soil moisture at the depth of 10cm in 6 randomly selected chambers (two chambers for each treatment).
Other
Photosynthesis
Occasionally
Ecological Investigation
Tree heights, stand density, diameter, biomass, LAI
Phenology
Continuous (photos)
Calibration Information
Open-path analyzers were calibrated approximately every two months with standard CO2 gases and a dew point generator (LI610, LI-COR).
The gain of CO2 of the closed-path analyzers was checked once a day flowing two standard CO2 gases of 320 ppmv and 420 ppmv that were automatically controlled using a programmable data logger (CR23X during 2006-mid-2007 and CR3000 after that, both were made by, Campbell Scientific, Logan, UT, USA.)
Infrastructure
Tower (35m), Electrical power (AC), Internet communications is available.
