Nagoya University
NagoyaUniversity

Depth Profilesof Radiocarbon and Carbon Isotopic
Compositionsof Organic

Matterand C02 ina Japanese ForestArea
WeiLIUi"
iDepartment

JunMORIIZUMIi

HiromiYAMAZAWA'[[bkaollDA'

SchoolofEngineering,
Nago.ya University
qfEnesgy Engineeringand Science,GraduatedE-mail::liztwei tanucLnaoa-u,ac.'lbl/ (052)789-4677
Fax:(052)789-3782

Abstract
specificactivities of i4C

andAa4C withinin organic(Ai4C)

isotopiccompositions

carbonmatter

C02 in aand

For investigating
the transport of C02 insoii, the specific activities ef
determined.

Japanesefbrestsoil were
V4C

and

the

organic

layeron the top of soil sutface
i4C

and

C02 werc

the atmospheric

also

determined.
The specificactivity of

depthofO - 60 cm

that of the soil C02 was not significantly variable at the soil depth of I3 - 73 cm and

while

was

largerihan that inthe atmospheric

cm

and

At4C values

wereA]4C in the organicandmatter

C02. Peaks of specific activities of t4C appeaTedthe depth of 15 cm

to originate
respiration

onlyin the objectivewasestimated

up until

depthof O - 4

to have seasonalmattervariations

and

and

- 73 cmthe respiration

be the mainthat thel963 and the bomb C had

The soil C02 at the depth of53

soil area.

from the decompositionof soil organicof liverootsat thepositivein the depth range from O to 15 cm. These results suggested

presentsoil at depthof O - 4 cm had been produced since the mid-1950sreacheddecreascdwith the increasingsoil

sourceofwereassumedliveroots, theofthesoil C02 at

the deeperhorizonsin the presentfbrestarea,

Key words:

soil, soil C02, soil organic

matter,specific

activity ofi4C,

carbonisotopiccomposition(Ai4C),

depth profiles,
sources.

-155NII-Electronic Library Service

Nagoya University
NagoyaUniversity

1.Introduction
Radiocarbon isof concern

in healthphysicsbecauseof itspotential
inventory,
rapid mobility,

halfllife
et al., 1991).Two thousands Pg of carbon includingradiocarbon(5730y) (Amiro
exist as soil organic(SOM) and the SOM

matter2000).Radiocarbon in the SOM
roots

atmosphere,

andradiocarbon

by plantsthrough bothdirect
and indirect
uptakes fromto give a part of the radiationdose te the globalpopulations,The

As theAi4C value iszero foratmospheric

Ai4C value indicatesthe presence of carbon

i4C

labeledwith

theAi4C in SOM can show
(bombcarbon). Consequently,

in SOM

Since radiocarbon
essential

exchanges

ultimately

physicsand the study en carbon

ofhealthi4C

produced by atmospheric

Ai4C in SOM

andnuclearandS-C02 simultaneouslyonthe activity of S-C02 due to the dicaculties
of determining the specific activity of i4C

fewer studies have been concernedonhavebeen donetransport in soil. Some studies

the variation

the specific activity of

weaponsin soil.

carbon

on

of

with

C02 as soil C02 (S-C02),
itis

atmospherici4C

of a standard

C02 in the year AD 1950, the positive

the transport ofbomb

withto study depthprofilesof the specific activity ef

fromthe viewpoints

to60 Pgy'i(IPCC,

atmospheric C02 at about

with

be indicatedby Ai4C, the permil (%D)deviationfrom the i4C/'i2C ratio

canisestimatedthe fbodchain

entcrsrespectively

fixedisotepiccomposition.

testingexchanges

long

and

(Guoet al., 2003) while few studies have been donein SOMvariations

the specificof

activityofi4C

in S-C02. Muchin SOM

andS-C02

simultaneously.

Forestecosystems

constitutethe major

1990) and have little
man-madc

effect.

transport in soil, In the presentstudy,

and Ai4C within

specific

activities

the organici4C

bothsoi) andoflayeron(AMS)(Nakamura
sizes, aboutallows1OOO times smaller than that needed

2. Materials andglobalcarbon

were

i4C

and

et al., 1990;Tan et al.,(Houghton

be a good objective

soil air atsoil surface

in all these samples

et al,, 2004),which

ofthe

Forest soil would

Depth profilesof their specific activities ofcollected.
i4C

reservoir

fbr the studyof carbon

ditTerent
horizons
in a Japaneseforest
soil wereandAt4C wereobtained.

C02 were

the atmosphericmeasuredwiththe specific activity of

fbrconventional

i4C

The specific

an

also

accelerator

measurement

decay counting

activitiesofdeterrnined,
The

mass

spectrometry

on very small sample

methods.

methods

2,l.Sitedescription
The experimental
witha meansite

elevation

leptolepis)
averagingwitha depth of7at the depth ofO-3

ofN and 137034'E) locatesinInabu,Aichi Pref,Japan,as shown(35e13'1010 m. The site is fbrestedwith

about

40-year-oldJapanese larch (LaLix

23 m in height.The soil belongsto a brown fbrestone. Itiscovered
cm,

which

cm,

consistsofa

3-cm leafllayer(L)andyellow-brown at 3- 13 cm

andin Fig. 1,

by an organic layer

a 4-crnfermentation-layer.
The soil isdark

tan below 13 cm.

- 156NII-Electronic Library Service

Nagoya University
NagoyaUniversity

35'N

Fig.1 The locationofexperimental

2,2.0rganiccarbon
Twosets ofcharactcristics

soii sampies

and

were

collected:one

the value

ofpH,

to determine itsspecificmeasurement

Additionally,
the specificrespectively,

methedandwere

set wasused

to analyzebulk density,particledensity,volumetric

as

shown

water

the physicalandcontent,chemical

air-fflled porosity,

in Table 1. Another was treated with the high temperature

as shown(HighVbltage Engineering Eurepe, The Netherlands)

pretreatmentfbllowed by the AMS

combustion

the samemeasurementsof soil suchcontent of SOM

site,

activity ofactivity of

i4C
i4C

and
and

Ai4C. The results wereshown

Ai4C in the organic layerwere

in Figs.2 and 3,
aiso measured

within Figs.2 and 3, respcctively,

2.3,Airrneasurements
About 500-mL
200-mLsyringe.

organic layerwas
collected

soilJapan) withsarne method

air

was

collected

atdiffercntsoil depth through the gas-colleetion
probesby a

Additionally,a 7000-mL of atmesphericcollected by a pump with airflow

air anda methanizer

used

soil

atmosphericandair wererare offirstlymeasured

500 mLmin-i,

withand werealso shown

The C02 concentrations

a gas chromatograph

FID. Then, Their specific activities offbrthe soil samples

heightof O, 25 and 50 cm

air at either

i4C

and

above

the

in both(GC-14A, Shimadzu,

At4C were determinedwith theinFigs.2 and 3, respectively.

-l57NII-Electronic Library Service

Nagoya University
NagoyaUniversity

も三雪OQQ NQoO
N穹．．．．ひ、． 藷
頃．

伺
o

工
二

寸
Dp

寸

」

寸

寸

創

寸

寸

り

。

慧
日
Q

冤o （

」求
一
，、 ． O ． ．鴇．、頃．．O ，N ， り，．Do ．［．O ．邑、． ．
． 冖、＝．コ、＝， O鬥巴 望
O
O
ON
望
【
9 雲
三 コ ［望 N冖N
；
皆 ）
｝
。

D9

£

卜

OQ

寸

門

噴

n

寸

ト

リ

卜

ひ

閤

。

ト

ト

唱

ひ

ひ

寸

卜

。
口
。

∪

． 卦
の
四 攀
お （
畧
・
雰
）
吻
冨
［
邑
ろ
・
・ −
ち
・
・ く
。

仙

・

（
b。
白
n
（
）
ゆ

悶

．．．． Pt PtP1
O
O

O

RO窪

寸

寸
寸

望

4

寸

寸

「

寸

寸

冖

．O ．O0 ．N 、．OO閏．m ． 唄．O ．、【．．．Cm ．ρ
． ＝”
う
冖日
壌
一20
N

QQ

り

α
寸

寸

卜

ひ

Qom

寸

寸

鴇

寸

め

ト

葛
ε

起

。

三

2

“
譯
〉
聾
・、

」

琶

2

蕁

2

三
超

Q

据
Φ
亳
で

冒

2

口

OO

。、

≧

お

（
o
窒
嘱
8
田 ）

三

σ
Q
・

黒
鼠

。
ξ
【
。

＝

謡

ひ門
o
丶
D

仁
ω

口

窟
酎

焉
≧

a

mPt

寸

P 蔑 16i

蹉

m
寸

一鴨鴨ひ
e

an

DQ

um

um

い

巷
祠

℃
t

cり

寸

三

寸
m

書
哥
薯

鴨omNNO 丶
Do
o 丶
卜

℃

〇

〉

邸
で

島

← （
あ

簷
咢

。

．
鍍

鋤

三

籠 e

一
回
c
【
．N ．．ONO ． N ．． N ， 鴇、 N ．．N ．り．．ON2 ，N ． O ， ，O ．、．N ．．c．
N

）o
頃
囚

つっ
頃

寸
寸

頃
囚

寸
寸

寸
m

頃

倒

囚

卜

寸

ひ
頃

ゆ

¢

寸

寸

卜

創

酎

四

り

卜

内
卜

寸
卜

円

国

個

個

蝸
卜

寸
卜

め
ひ

創

国

【
囂
「
咽
・

2
つ

鬚

山

日

（
言
の

Φ

り
葛． 它．．
O ．c．

口

。
で

ヨ
臥

ひ

卜

当

♂

蠡 ）

（
巳
）

二

気
。

O

り

O

O

ON

Φ

驚

寸

O

O

頃

偶

ひ

い

寸

卜
卜

卜

α

凶

り

Q

耐

卜

寸

ゆ

¢

−

承
09
O

O

司

寸

−一 − −
O 偽 20 黷
り

2
O

O
OQ
シい p O O．OO 、oOODQ．QcO ．DoO ．曽， り．O ．ODO．ODoOo、O ．9［．一， O ，OOO ．Q ．OO ．O ．QgDQ
．Hn
、【． 8
O
創

じ

鴨

09

コ
ー− NONON
−
り
ーd偽 一
【 鴇
O
〇

〇

頃

Om

Σ 寸OO

鴇 酎

←・

ζ

oc

り

り

頃
寸

寸

り
寸

．
。
°O）
〔

h
＝

O

，9』− 偽 O− − 偽O 頃コ NON
り

五 寸

寸

。

OO

尸

α
個

N

い

9− 斜 り− 寸− り
、鴇− −
り
Om

℃
O

嶋

コ

NO

O

O

鴎寸

○
り

OO

（．

躔

。

×

F

．

ご

＞

oZDo寸

ど

OO
ぺ

一 158 一一

NNII-Electronic
工 工 Eleotronio
Library
Library

ServiceNagoya University
NagoyaUniversity

5peclTL'uc/r,':ty
1titl
fiO"tL.CO
:c

IHO

?OO

'r,

2tiM"y-MJuLvV!

i'C Xg 'C/･

{d'

/1]u

t,20

2gC

'"-

"

-loD

2602HO---2/m ,-o

/,c
c,bo)
o
-L

s//

i

/ao/1

t

･10

l

loo

/

'z

,/

i

gS,,pu･/nL,,,rt.-E.･--."i'''''"11･1/,1"'''''''''C'1;}
'''
-n

80

iiC/

SpeciLie/ict-'/ryod'
L:O

230

2,w

\

IllO,

.1

{al

,･' 50O

CBq..giC)

L,su

rso

d"c'{tsv)
T5

]OO

//l5

ISU

1'/･E

t,OO

17/)

t-

----Org//nit[ayerst//'!li/.v-･･-l-i---･･
-

s

i

b

aver
i

iko[g,,/e.-.""t'.N....
tt;''---so/iliuriace･---------･--L--...
e ''
.;:

S

/

l,i.rf.-v.ti,,.
1!--L;III-:Lsigi/tg-tto

Fig. 2 Specific activity

'"C

of

in the SOM (Soil

I4

Figure 3 The A C values

the SOM,

withinthelayer,the S-C02 (Soilorganic

C02. The

and

C02. The verticalandtransversaibarspresent

transversalbarspresentthe depthrange of collected

the depth rangeofcellected

organic

matter),the organicC02) and the atmosphericsampledandcounting

venicalrespectively. The
(16),

error

bottomFigure istheexpansion

oftheb area lnupper

Figure.

layer,the S-C02

counting

error

the atinosphericand(lu),respectively.

Figure is the expansioR

samplesand

The bettomof the b area

in upperFigure.

3. Resultsand discussions

3,l.Depthprofilesof specific activities of i4C and Ai4C in SOM
The specific activity of

i4C

and

S-C02

inthe SOM (Fig.
2) decreasedwith the increasingdepth.Itwas in the range

from 262.3 t 2.3 to I94,I ± 2.3 Bq.kg'iC at the depth of O - 25 cm,

which

was

in agreement

with

that

by Guo et al. (2003),
who gave 281- 200 Bq.kg'iCin the SOM
at the depth ofO - 22.5 cm in threepublishedJapanesesoil samples collected in 2001. The specific activities of i4C in SOM were different
at different

herizontal
posnions.They were 236,7± 2.2and 21 1.6± 2,4Bq.kg'iC at the depth of lO - 15 and 20

venicaland- 25 em,

respectively,

fbrthesoil cellected-25 cm fbrthe soil coliectedonon

8 Nov.; however, itwas 209,8± 1,8Bq.kg-iC at the depth of 15

l3 July. At the same depth,such

238.6± 2.1,239.7± 3.I and 233.5± 2.2Bq.kg'iCfbrthe soilsample

as at thedepthof4-7

collected oncm,

itwas 243.2± 2,2,

26 May, l3 July,9 Sept and 8

Nov.,respectively. This might be related to soilheterogenejty,
i4C
Additionally,
inthe SOM
peaks of specific activity ofsoils samples

collected

on

26 Mayand2) appeared(Fig.

at a depthof2.

4 cm inthe

9 Sept.while they appeared at the depthof O - 2 crn on bothof l3-159NII-Electronic Library Service

Nagoya University
NagoyaUniversity

8 Nov. It is known that the specific

July andup

mid-1950s

1963 due te the release

untilsuggested to be the residues
otheractivityofi4C

in the atmosphereby Rucleari`Cof specific activities of

i4C

of

i4C

The specific activitiesof
collected en 8 Nov. were

inthe SOM producedin the mid-1950s

inthe S-C02 (Fig.
2) at the depth of 13-73

offbrmer ones

collected

onlessthan the latterones

200.9± 1.9Bq,kg'iC was

thisSOM, the decompositionof SOM

1963.

until

and the organie layer

plant,the specific activity

i4C

of

on

at deeper soil horizons,For example,

depthof50-55

i4C

inthe

at theday, thethe same

cm,

while

about

242.9±2,4 Bq.kg-iC fbrS-C02.If there isno

in SOM

andthat in the S-C02 derived
from decompositionof

at the deeper horizon isnot

to be the mainsuggestedsourceof

S-C02

deeper horizon.

The C02 difTUsesin soil in the two ways: throughthe soil air pores and2004). Sincethe diffusioncoeencientwasup

8 Nov. with those in the S-C02 co]lected

forSOMobserveddifference
betweenthe specific activity ofat the samecm

1963. In

until

to be close to 242.8 Bq.kg'iC.Comparing the specific activities of i4C inconsidered

the soil samples
were

be

inthe range from 238.8± 2.2 to 244,5±2.3 and 242,8±2.4 Bq.kg'iC,respectively,

Sincethe ]iveroots and the organic layersbelonged to thc same
presentliveroots wasfromtesting. Thus, the peaks canweapons

the present
soils at the depthofO - 4 cm have been produced since the mid-1950s

words,

the SOM

increasedstrongly

reportedofC02

in air isgenerallymuch

the soil water

et al.,(Jassallargerthan that in water, forexample,

ten thousands times thatinwater

to be approximately

with

at 200C by Robinson andit(1959);

stokesPritchardand Currie (1982),
the diffUsionof S-C02 through the soil air pores are muchtban thegreateri4C
transport of S-C02 with the soil water. Thus,ifthereisno depthdepefidency
efthe specific actiyity ofini4C
S-C02 fromthe respiration of liveroots, the similarity in the specific activities ofbetweenthe S-C02 andliveroots at the deepersoil horizonindicatesthat the respiration of liveroots may be the dominant source of

S-C02 at the deeper soil horizons,
The specific activity of i4C in the atmosphericBq.kg'gC,
which

isalso approximatelysame

C02 (Fig.
2)isintherange frorn242.2± 2,3to 246,4±2,3depthof 13 - 73 cm. This may imply thatas that in S-C02 at theC02 enters the soil air. The air-fi11ed perosityofthe present
soil ranged
from 1O,Oto 49.6% at a
depth ofO-20
cm and about 4,1% at a depthof 40-60 cm, as shownin Tiiblel. This indicatesthat theatmosphericvertical exchange
volumeof S-C02 through the soil pores is stronger

at O-20be corresponded

volumeof collectedsoil air can

to a spherical

cm

and

weakerat 40-60of soil, the radiuscm.

Jf theisestimatedto belessthan 1O cm fbr500-mL of soil air at the depthef 13 cm because the air-filled porosgty at the same depth
islargerthan 1O%, The 500-mL ofsoil

air sample

3 - 23 cm. The effbct of the enteringof atmosphericat thedepthef 13 cm

mayconsistofthe air at the depthof

C02 had been reported te be importantat very

shallow

depths(lessthan 1O cm) by (Cerling
et al,, 199l; Hcsterberg and Siegenthaler,
1991),se thatthe 500-mL soil
air at the depthof 13 cm might

exist theentering of atmospheric

The Ai4C in the SOM (Fig.
3) decreased
withappearedat the depth ofO

that collectedon- 1O cm

in soil samples

8 Nov., respective]y.

air.

the increasing
soil depth.PositiveAi4C in the SOM

collected

on

26 May, 13 Julyand 9 Sept.and O - 15 cm inSince positiveAi4C value

et al., 2002), the soils at the depth ofO(Margarets- 15 cmis due to incorporationof

are considered`bomb

to dominate by the organicC'matter-160NII-Electronic Library Service

Nagoya University
NagoyaUniversity

fixedinthe last50 years. Therefbre,one can be concluded

that the bomb C has reached

the depth of 15 cm

inthe presentsoil area.
The Ai`C in the S-C02 (Fig.
3) werewithof that in SOM

the variation

not significantly

samethat inthc SOM at deepersoil horizon.For example,

that inthe organicasthat the decompositionof SOM

layer.
Itwas- 73 cm

largerthan

much
on

8 Nov., itwas- 55 cm.

-1OO.3± O.5%o at the depth of50

wasat the deeper horizonisnot

the mainsourceofdeepersoil horizon,

S-C02 at the same

3.3.Quantitative
estimationof

S-C02 originations

The S-C02 at the depth of53
ofcomparinginthe S-C02 were larger

the S-C02 at the depth of53

in the range from 72.0±O.3 to 82.6± O.4%o while that ofthe SOM

the respiration

depthof 13 - 73 cm

the increasingsoil depth,The Ai4C values

withthan that inthe atmospheric C02 and approximatelyThus, itcan also be concluded

at thevariable- 73 cm isassumed

liveroots, basedon

a massto originate only

balance approachoffromthe decompositionofSOM

i4C02,

the fbllowingequations

and
can

be

obtained:(1)

Rr+Rs=i,A14ci=RrxAi4cr+RsxA14Cs･(2)
Combining Eqs, (1)with

Rr=A14ci-A14Cs

R, and R, stand(3)'

Al4cr'A14Cs

where

onc can obtain:(2),

fbrthe fractional
contributionsof the respiration

oflive

roots

and

the

decomposition

the Ai4C in the S-C02,
SOM to the total S-C02 concentration, respectively; Ai4C,,Ai4C,and Ai3C,present
Since the effects
those derivedfrom the respiration of live
roots and the decompositionof SOM, respectively.
andPolach,1977),thewith
norrnalizationby 6i3C(Stuivcr
ofisotopic
fractionations
on Ai4C arc eliminated
Ai4C in the S-C02 derivedfrom the respiration of liveroot can be inferredto be that in the same plantitselfofAdditionally,
littleor nosignificantly

seasonal

occurredvariationsin the Ak4C within the planttissue and theSOM. The Ai4C vaiue inthe S-C02 derivedfrom the liveroot-respiration
85.1%o,whichisthe AT4C value

in the organic

Ai`C value inthe SOM at the depthof 50 - 55 cm

onbe estimatedte be closetoin Fig.3. The Ai4C value inthe S-C02 derived

layershown

from the SOM-decomposition at the depth of 55 - 73 cm

can

can

be inferredto be lessthan -lOO.3%e that is the

8 Nov. due to the decreaseof AT4C in SOM

with

the

increasingsoil depth.From Fig.3, the Ai4C value inthe measured S-C02 were 69.7,95,O- 70.6 and 82.6 53 - 73 cm on 9 Sept and 53 - 73 cm on 8 Nov.,
77.3%o fbrthe S-C02 at the depth of 53 cm on 13 July,
respectively.

the R, at these depths were
Using Eqs. (l)- (3),estimated

to be 92%, largerthan 929t6and-161NII-Electronic Library Service

Nagoya University
NagoyaUniversity

largerthan 96% on 13 July,9 Sept,and 8 Nov, 2004, respectively. Therefore,one can be concluded
that thefractional
contribution
oftheliveroot- respiration in the deeperhorizon(53- 73 cm) inthe presentsoil may
have a seasonalvariations

isthe main

the liveroot-respiration

andsourcethe S-C02 at the deeper soilofhorizons.
4. Conclusions

The specific activity of i4C
that in the S-C02 was

Ai4C in SOM decreased
with the increasing
depthfrom O to 60 cm

not significantly

C02, A peak of

atmospheric

and

]4C

at the depth from 13 to 73 cm

variable

specific

activity was

the present
soil at the depth of O - 4 cm

and

up

until

inthe depthrange from O to 15 cm impliesthat the bomb C have reachedsoil,presentforest
activity of

i4C

and

Ai4C in the S-C02 were

hQrizons(53- 73 cm). This impliedthatdecomposition
of SOMsame

deeperhorizon.If the S-C02 at the deeperhorizon was

sourceat thedeeper

S-C02 at theoffrom thethe respiration oflive roots, the respiration of liveroots was estimatedto have anandseasonal

be the mainandthe mainnotin theonly

decompositionof SOM
variations

1963. Positive Ai4C

largerthan that in the SOM
wereimpliedthat

which

the depth of 15 cm

values

The specificlargerthan thatin thefbundat the depthfromO to 4 cm,

had been produced since mid-1950s

while

sourceofto originate

assumedthe S-C02 at the deeperhorizons(53- 73 cm)

forestsoil basedon the isotopemass balance
approachinthe present]4C02,

forAcknowledgements

The authors

liketo thank Prof T, Nakamura,Ms T, Ohta and Ms. A. Ikeda,Nagoya UniversityCenter

would

forChronologicaiResearch,fbrtheir cooperation

inmassspectrometry

measurements.

The authors

also wish

to thank Profi E. Shibata,
Mr. Y/ Imaizumi, Mr. N. Yamaguchi, UniversityForest,Graduate School of

Bioagricultural
Sciences,Nagoya University,
fbrtheir kind assistancethe site. This research

Future,Nagoya

wascarriedout as a partofthe

2ISrcentury

andadviceduringfieldexperimentin

COE program on IsotopesfbrProsperous

University.

Reference

Amiro,

B.D., Zhuang,YZ, Sheppard, S. C., 1991.Relativeimportance of

pathways fbr

i4C02

transferfrom contaminatedsoil

to plants,HealthPhysics

atmosphericroot

uptake61, 825-829.

Cerling,T. E,,Solomon, D. K,,Quade,
J,,Bowman, J. R., l991. 0n thc isotopiccompositionsQii carbon

andofcarbonindioxide.
Geochimica et Cosmochimica Acta 55,3403-3405.

-162NII-Electronic
NII-Electronic

Library Service

Nagoya University
NagoyaUniversity

i4C, i37Cs
andGuo, J, F.,Andon, M, A,, Amano, H,, 2003. Variatienof
soil anditsimplicatiens.
JournalofRadioanalyticalandstable carbon

infbrest

composition

Nucleal Chemistry 255, 223-229,

composition
R., Segenthaler,U., 1991.Production
and stable isotopic
Hesterberg,

in a soil near Ber.

ofC02

tc11us 43B, 191-205
Switzerland.

Assessment.
Houghton, J. T.,Jenkins,G J.,Ephraums, J. J,,1990. Climate Change: the IPCC Scientific
Press,Cambridge, 364pp,
Carnbridge
University
CambridgeUniversityPress,Cambridge, UK.
IPCC, 2000.Land use, land use change, and fbrestry.
Jassal,R. S.,Black,T. A., Drewitt,G. B., Novak, M. D.,Guay, D. G, Nesic, Z., 2004. A model
soil C02 concentrations
productionand transportof C02 {n soil: predicting

andC02 efflux froma fbrest
floor.

124,219-236,

Agriculturaland ForestMeteorology

Margarets,T.,Anatoly,T.,Marcl, F,,Borisv,B.,Jenniferw,H,, 2002. 0rganic carbon
modernandof the

1OO-year-old-soil
archives

ofthe

and

isotopesin

carbonRussian steppe, GlobalChangeBiology 8,941-953.
i`C

Nakamura, T,, Niu, E., Oda, H., Ikeda, A,, Minami, M,, Ohta,T., Oda, T., 2004. High precision
measurements

withthe HVEE

Tandetron

AMS

systemat

Nagoya University.Nuclear Instmments andMethodsin PhysicsResearch B 223-224, 124-129,
Pritchard,
D, T,,Cunie, J. A,, i982. Diffusioncoefficientsethaneinair and their measurement.

dioxide,nitrous oxide, ethylene andof carbon

33, 175-184.
Journalof SoilScience

Robinson, D., Scrimgeour,C. M., 1995. The Contributionof plantC to soil C02 measured

using

6i3C.Soil

27, 1653-1656.
BiologicalBiochemistry
H. A., 1977,Discussionreportion
Stuiver,M.,Polach,ofi4C

data.Radiocarbon 19,355-363.

constraints
fans, P,P.,Fung, I,Y., Takahashi,T.,1990. 0bservationalon

the globalatmesphericC02 budget.

Science247, 1431-1438.

- 163NII-Electronic Mbrary
NII-Electronic
Library

ServiceNagoya University
NagoyaUniversity

1 ．Referencepublication
WLiu
J．Moriizumi ，H ．Yamazawa T Ida 2005 ．Depth Profilesof i4C in Seil Organic
Carbon and in SoilCO2 From a Forest Area ．Journal of RadiationProtection Bulletin．
Special issue，269 −271 ．
，

，

，

，

W ．Liu ，J ．Moriizumi H ．Yamazawa ，T，Ida，2005 ．Depth Profilesof Radiocarbon andCarbon Isotopic
Compositions in OrganicMatter and CO2 in a Forest Soil．Journal ofEnvironmentalRadioactivity （Reviewed）．
，

2．Internationalpresentations
WLiu ，J ．Moriizumi ，H ，Yamazawa T ，Iida，2005 ．Concentrationand Carbon Stable
IsotopicCompositionof SoilCO2 in a ForestArea： Estimation of source of soil CO2 ．
，

international Symp ・曲 m ・n 」s t p
5冨 θ刀 ・θ’・
Applica tjons ．Nagoya，Japan Sept ．21 23 ．
・

・

a ・・ゴ

θ

劭 卿

θ

・

血

堵

．
Basies・切‘・，W6i HU ，Jun MORIIZUMI HiromiYAMAZAWA，Takao IIDA 2005 ．Depth Pro五lesof
Radiocarbonand Carbon Isotopic
Compositionsof Organic Matter and CO2 in a Forest，，’
Soil．24th Mi llerConfereneeon RadiatiollCh
Sept ．ユ0 ・
15 ．

θ mistjア

La Londe lesMauresFrance ，，WLiu J ．Moriizumi ，H ．Yamazawa and T ．Iida 2005 ．Depth Profilesof l4C in Soil
Organic Carbon and in SoilCO2 From a Forest Area ．Proee θ伽 gs of tゐθ th か ゴ ∫7 嬲
，

館

翩

，

・

伽

・

／亀 脚

曲

・

’

加

n ・ R ・ diation Safety and・）．
0 ・オ・・tion Teeim・厂ω 0 κZ 冫一
3？．

Taiyuan ，China，July 27 ・
28 ．
3 ．Domestic presentations
劉衛

森泉

純

山澤

弘実

飯田

孝 夫 ，カ ラ マ ツ 林 土 壌 中 の 有 機 物 及 び 二 酸 化 炭 素 の

炭 素 同 位 体 比 ．日本 原 子 力 学 会 春 の 年 会 ，（
平 成 17 年 3 月 ） ．

劉衛

森泉 純 山澤 弘 実 飯 田
孝 夫 ，森 林 土 壌 中 の 有 機 物 及 び 二 酸 化 炭 素 の 炭 素 同位 体 比 に よ っ て 土 壌 炭 素 循 環 に つ い て 研 究 ．第 3 回 同位 体 科 学 研 究 会 ，（
平 成 17 年 3 月 ） ．

森 泉 純 山 澤 弘 実 飯 田 孝 夫 ，森 林 土 壌 中 の 有 機 物 と CO2の 分 布 ．日本 保 健 物 理 学 会 第 39 回 研 究 発 表 会 （平 成 17年 6 月 ） ．
劉衛

の

14C

比放射能

一 164 一一

NNII-Electronic
工 工 Eleotronio

Library Service