Watershed-Scale Experiment on theCarbon Cycle of Larch Plantation
Carbon Cycle and Larch growthExperiment

Carbon Cycle and Larch Growth

CC－－LaG Experiment・National Institute for Environmental Studies
・FSC for Northern Biosphere,
Hokkaido University
・Hokkaido Electric Power CO., Inc.

Since 2001

Lat. 45oN
Teshio Experimental Forest

30 m Tower

Observation WeirN

Study area
(13.7 ha)0100200 m

●Study site
Teshio Experimental Forest, Field Science Center for Northern
Biosphere, Hokkaido University（45º 03’N, 142º 07’E, a.s.l. 66m ）●Main Project
P0 Carbon dynamics monitoring in a young larch plantation●Sub Projects
P1 Biomass research of a cool-temperate forest
P2 Carbon dynamics monitoring in acool-temperate forest
P3 Effect of regeneration managementson the carbon sequestration
P4 Watershed-scale carbon/water/nutrient dynamics
P5 Evaluation of regional carbon budget
Monitoring terms
Biomass & Spectral vegetation index
measurement using remote sensing

Flux measurement

CO2 conc.
Wind direction
Wind speed
32m
32m

Measurement on the top of the tower
3D wind speeds

25Biomass & matter flow
surveys

Air temperature& Relative humidity

・Biomass, Leaf Area
・Snow survey

21・Water chemistry ofThrough fall and Rain fall・Deposition amount・Water chemistry of soil water

15

Open-path
CO2&H2O
fluctuation

Radiation
Sensors
Precipitation
Spectral
Vegetation Index

Flux measurement nearvegetation surface

10

Soil & Sasa (& larch; until 2005)
CO2 flux using chamber 6
Snow melt

NOx, O3, NHx gas & aerosol
concentration measurement
at two heights

4

Snow depth

5cm
105cm
10

CO2 concentrationin the soil

3060

Measurement term at the weir
・Runoff: Water temp.: EC・Water chemistry: SS1 cm1 cm
5Soilheat
10flux204080120
Soil water content Soil temperature

Study on the CO2 sequestration capacity of forest
CO2 flux can be evaluated by measuring
vertical wind velocity and CO2 concentration
continuously with high frequency.
Our principal aim is to evaluate the effect ofdeforestation and afforestation on theecosystem carbon budget by monitoring theCO2 flux under the series of these activities.
2001-2002

2003

Instruments for CO2 flux
measurement

2004-2005

Tree logging

Emission

10-1-1CO2 flux (tC ha yr )200-10

Strip-cutting undergrowth Sasa
& Larch plantation

8 years observationshows that the deforestation decreased thephotosynthetic capacity
and increased the net
CO2 emission rate fromthe ecosystem.
However, the increase in
the Sasa photosynthesis
decreased the CO2
emission rate rapidly.

14.0
10.5
Respiration

10.4

11.7

11.5

12.3

12.2

10.6

-0.4

5.0

1.5

1.2

0.04

1.0

0.3

5.7

Net exchange of CO2

Photosynthesis
-14.4

-4.8

-5.4

-10.1

-10.3

-12.3

-11.2

-10.4

2002

2003

2004

2005

2006

2007

2008

2009

-20

Sequestration
We will continue this monitoring in order to evaluate the effect of tree growth on thecarbon sequestration capacity of this ecosystem.

Study on the hydro-biogeochemical cycles offorested watershed
We also evaluates the water balance of thisforested watershed by observing rainfall, snowfall,evapotranspiration and water runoff of the stream.
Additionally, we evaluates the carbon and nutrient
outputs by the stream water by periodic collection
and chemical analyses of the water.
Observation weir and litter trap

Rain water & litter arecollected periodically andthe chemical components
are analyzed．
Watershed area: 8ha

Litter trap and rain collector
Dry and wet deposition collector

25DOC
DIC
POC（>0.7μm）
リター（>4mm）
Litter
流量Runoff

400
300

2015200

10100

5004080120160200240280320

Runoff (l s-1)(l s-1 )河川水流量

Cumulative
carbon output
積算炭素流出量
(kgC)
(kgC)

500

0360

DOY 2002

Observation in the mixed forest shows thatca. 80% of the input water was flowed out by the stream.
ca. 20% of the fixed carbon was flowed out by the stream water.

Study on the large scale forest biomass
estimation by airborne surveys
3D forest image obtainedby airborne survey

Airborne laser survey detects
3D structure of forests byshooting laser from airborne andsensing the reflection.
We are developing theestimation method of large scale
forest biomass by relating theairborne data with the groundsurvey data.

3D forest image obtainedby airborne survey

GPS

Tree canopy

Ground survey (tree diameterobservation)-1

800

3Ground
地面 surface

Timber volume by ground survey (m ha )：laser：reflection

Schematic diagram of airborne laser survey

Y=0.0021X+61.26
2
r =0.80600

400

20000501001502003250x103-1Canopy volume detected by Lidar (m ha )Layering airborne 3D data (Grey-white) andground surveyed canopy crown map (Green).

Relationship between ground surveyed timbervolume and canopy volume detected by Lidar.

We are also conducting
traditional biomass survey for
major tree species in the cooltemperate zone, in order toelucidate the carbon
allocation in a tree. It takes
much time but is important
basic data in order to consider
the allocation of fixed carbon
by tree photosynthesis.

Washing roots for weighingSeparation of leaf and branch

Tree cutting

Washing and categorizing roots

10000

Dry weight（kg）

Birch above groundOak
Fir

Biomass allocation （%）

6050

OakBirch
Fir

40
301000

Birch below ground
Oak
Fir

100

1020
1010
Leaf

BranchStem

Root

Biomass allocation for major tree species
in northern Hokkaido

1
10100
Diameter at breast height (DBH: cm)

Relationship between DBH andthe dry weight.

Study on the CO2 exchange rate ofecosystem components
Continuous chamber measurement elucidate
the CO2 exchange rate of each ecosystemcomponent (i.e. soil, Sasa, larch) . Open andclose of each chamber lid are automaticallyregulated. When a measurement starts, the lid
close and the change rate of CO2 concentrationin the chamber is logged by data-logger.
SoilLarch
saplings

8

Sasa

EddyChamber

64

CO2 flux (gC m-2 day-1)

Results obtained during 1 year afterlarch plantation shows that the soil islarge carbon source of this ecosystem
and larch has little CO2 sequestration
capacity. Sasa community tend to bea carbon sink during the late summer,
however the annual budget was still
positive (i.e. carbon source).

20-2-48Soil
Sasa
Larch

64
20-2-4060

120

180

240

300

360

DOY2004-2-1

CO2 flux (gC m d )16

LICOR soil respiration
TER
Liang_soil respiration

12577
1301

-2-1

g C m snow-free preriod

673
1010
852 (84%)8951
1047(110%)1096
1062(97%)1063
981(92%)

1173
1105(94%)

40Jan

Jul
2002

Jan

Jul
2003

JanJul
2004

Jan

Jul
2005

Jan

Jul
2006

Jan

Jul
2007

Jan

Jul
2008

1121
1035(92%)

Study on the spectral vegetation indexes
Surface vegetation has its own
characteristics for radiation reflection and somecombination of the reflected radiation bands
are proposed to explain the photosynthetic
activity of vegetation. We are relating the real
CO2 fluxes to several spectral vegetationindexes, in order to estimate carbon fluxes
more precisely by remote sensing from space.

For example,
NDVI=(D-C)/(D+C)
Reflection from vegetation
A B

C

SAVI=1.5*((D-C)/(D+C+0.5))
D

PRI=(A-B)/(A+B)
NDVI:normalized difference vegetation index
SAVI :soil-adjusted vegetation index
PRI :photochemical reflectance index

400 500600

700 800 900 1000

Wavelength (nm)Best correlation was observed
between SAVI and photosynthesis
capacity for this site.

Photsyntheticcapacity

Spectral irradiance (W m-2 µm-1)

Solar radiation

SAVI

●Features
1. Clear-cutting of a natural forest& plantation of larch saplings
・13.7 ha clear-cutting
・Effect of clear-cutting on the matter flow
・Effect of plantation on the matter flow
2. Snowy region
・Snow depth ≈1.5 m
・Comprehensive understanding of hydrobiogeochemical cycle of a forest in snowy region

Flux measurement

3. Watershed-scale monitoring●Schedule

Observation on mixed-forest

13.7 ha clear-cutting(Jan.-Mar. 2003)

Hybrid larch (Larix gmelinii×
L. kaempferi) plantation(ca. 30,000 saplings) (Oct. 2003)

Tie up with Tomakomai Flux Research site
and Fuji Hokuroku Flux observation site
Comprehensive study on carbon
sequestration rate of larch forests

Papers on this project
・Koike, T., et al. (2001) Basic data of the study site for CO2 flux monitoring of a young larch
plantation located in the border between northern Japan and far east Russia-Current
status of a mature mixed conifer-hardwood forest stand -. Eurasian Journal of Forest
Research 2: 65-79.
・Takagi, K., et al. (2005) Deforestation effects on the micrometeorology in a cool-temperate
forest in northern Japan. Journal of Agricultural Meteorology 60, 1025-1028.
・Takagi, K., et al. (2005) Dynamic carbon dioxide exchange through snowpack by winddriven mass transfer in a conifer-broadleaf mixed forest in northernmost Japan. Global
Biogeochemical Cycles, 19, GB2012.
・Fukuzawa, K., et al. (2006) Effects of clear-cutting on nitrogen leaching and fine root
dynamics in a cool-temperate forested watershed in northern Japan. Forest Ecology andManagement, 225, 257-261.
・Fukuzawa, K., et al. (2007) Vertical distribution and seasonal pattern of fine-root dynamics ina cool-temperate forest in northern Japan: implication of the understory vegetation, Sasa
dwarf bamboo. Ecological Research, 22, 485-495.
・ Tsuji, H., et al. (2008) Summer relative humidity in northern Japan inferred from δ18O
values of the tree-ring in (1776-2002 AD)-Influence of the paleoclimate indices ofatmospheric circulation. Journal of Geophysical Research, 113, D18103.
・Nakaji, T., et al. (2008) Utility of spectral vegetation indices for estimation of light
conversion efficiency in coniferous forests in Japan. Agricultural and Forest
Meteorology, 148, 776-787.
・Takagi, K., et al. (2009) Change in CO2 balance under a series of forestry activities in a cooltemperate mixed forest with dense undergrowth. Global Change Biology, 15, 1275-1288.
・Hayashi, K., et al. (2009) Ammonia emission from a young larch ecosystem afforested after
clear-cutting of a pristine forest in northernmost Japan. Water, Air and Soil Pollution,
200, 33-46.