Varrio

68N-29E

Inuvik

68N-133W

Tura

64N-100E Fairbanks

65N-147W

周極域森林生態系の特徴 －より深く理解するために－

The peculiarity of circumpolar forest ecosystems.

- Beyond dogmatic concepts for better understanding -

国立研究開発法人 森林総合研究所 戦略研究部門 国際連携・気候変動研究拠点

松浦陽次郎 （チーム長 生態系研究統合担当）

Yojiro MATSUURA (FFPRI)

2016.05.21 北極域研究共同推進拠点 開設記念シンポ

Vegetation map in circumpolar region

Discrepancy between

vegetation zone and

permafrost boundary.

Climate conditions among circumpolar regions

Fairbanks (65N-147W)

MAT: -3.4°C

AP : 287 mm

C-index: 57

Kajaani (64N-28E)

MAT: 2.5°C

AP: 564 mm

C- index: 33 Tura (64N-100E)

MAT: -9.2°C

AP : 317 mm

C-index: 80

Yakutsk (62N-129E) MAT: -10.1°C

AP : 213 mm

C-index: 97

Nizhne-Kolymsk

(69N-161E)

MAT: -14.5°C

AP : 177 mm

C-index: 74

Fort-Smith

(60N-112W)

MAT: -3.1°C

AP: 353 mm

C-index: 62

MAT: 年平均気温 AP: 年降水量 C-index: 大陸性 気候指数

Soil map of Eurasian Continent FAO(1993)

Dominant Tree Species in Forests

West

Siberia： Pinus,

Betula

Central

Siberia,

Eastern

Siberia:

Larix

Vorob’ev G.I. (1986)

中学や高校でおなじみの地図帳ですが・・・

Zonal

Boreal

Forest

Zonal

Podzol

distribution

7 8 9

0

50

100

pH(H2O)

1) Thin organic horizon 2) Alkaline soil pH

3) No gley diagnostic horizon 4) Cryoturbation

Dogma in ecological textbooks

Textbook is not

always correct,

especially in

circumpolar

region.

Whittaker (1975)

Fig. 4.10.

＜邦訳 p.153＞

Whittaker 1975

Ice sheet expansion vs. Permafrost distribution

Schematic diagram of circumpolar forest biome development (modified from Matsuura 2004)

Deciduous conifer (Larix) dominant

Continuous permafrost Evergreen conifer (Pinus, Picea) dominant

Permafrost

type

Dominant

conifers Regions

Continuous Larix

Picea

Central Siberia,

Eastern Siberia NWT, Canada

Discontinuou

s Picea

NWT, Canada

Interior Alaska

Sporadic/Isolat

ed

Pinus

Picea

Larix

NWT Canada

West Mongolia

Permafrost free Pinus

Picea

Fennoscandia

N. Europe

Surveyed in 1993-2001

Surveyed from 90’s / continuing

Surveyed in recent 5years

Comparative forest ecosystem research sites

in circumpolar region (2016)

Udleg

Fort Providence

Norman Wells

Tura

Fairbanks

Fort Smith

Inuvik

Varrio

Hyytiala

Kalina

Kangasvaraa

Juminda/

Hiiumaa/

Saaremaa

Tiksi

Cherskiy

Oimyakon

Yakutsk

Yaktali

Carbon storage in larch ecosystems on continuous permafrost in Siberia

62

18

57143

12

9.1

5.883

8.512

8.7136

Yakutsk Tura Chersky

C in aboveground partC in belowground partC in forest floorC in active layer (SOC)

Unit: MgC/ha

Data sources of forest biomass: Kanazawa et al. 1994,Kajimoto et al. 1999a,1999b

Carbonate-C: 12.7Carbonate-C: 2.6

Carbonate-C: 0

Matsuura et al. (2005)

Yakutsk

62N-130E

Tura

64N-100E

Cherskiy

69N-160E

High allocation rate

to belowground part

永久凍土では通常の土壌と異なる要因で群落の構造変化が起こる

永久凍土地帯の生態系 通常の土壌の生態系

攪乱後 攪乱後

（ ） （ ）森林火災 伐採など

無機化促進

凍土面沈下 養分放出

～ 年後 ～ 年後20 40 20 40

凍土面上昇 個体間競争

年後 年後100 100

Schematic diagram of regeneration processes

on permafrost and non-permafrost soils Permafrost Non-permafrost

Permafrost

subsidence after

disturbances

Nutrient

release after

disturbances

Recovery of

forest floor and

permafrost

re-rising

Self-thinning

process starts

20 -40 yrs

100 yrs

Anomaly self-

thinning under

strong nutrient

limitation and

root competition

Stand

development

along normal

self-thinning rule

trajectory

Old root system was packed in frozen soil.

Kajimoto et al. 2007

Trees survived have 1) Ability and chance to elongate and extend new root system to non-frozen soil, when the old

root system was packed in frozen soil. 2) Ability and chance to elongate and extend new root system to the area where neighbor trees do not reach.

Carbon budget monitoring study by ecological methods

CO2 flux measurements during growing season

mid-MAY

mid-JUL

mid-SEP

CWD estimation 0 4 8 12 16

0

4

8

12

16

Distance (m)

Dis

tance (

m)

Snag

Stump

Buried log

Log on the forest floor

Legend

Buried log sampling

SOC

Rag Rs

Rh Rbg

NPP

Lag

Lbg DOC

Ao

5.7

2.6

unit: ton C ha-1

ton C ha-1 yr-1

1.4

0.2 0.1

0.8

0.1

1.0 12

71

0.8

NEP

0.8

0.1

1.2

? ?

?

Floor Vegetation

Permafrost

Biomass Increment

Larch Trees

Active Layer

Osawa et al. (2010)

Ice scar records on the tree trunks

indicate flooding level of spring

snow melt.

Reconstruction of snow melt/flooding regime

using tree ring data.

安江（信州大）原図

Forest fire, Permafrost degradation, Shallow root system

Fireweed after disturbance

Monitoring study on

2004 fire in Alaska

15cm soil 79.8

brown org. 36.3

undergrowth 7.90

10.5

3.8

15cm soil 63.3

Changes in C distribution

before/after fire disturbance

?

brown org. 21.5

8.75

3.5

4.40 0.31

unit:

MgC ha-1

estimated C loss = 37.3 MgC ha-1

Soil profiles in interior Alaska

Soil profiles in NWT Canada

Similarity 1) Bedrock 2) Glaciation / deglaciation 3) Lake formation 4) Histosol / Podosol

Difference 1) Present climate 2) E-W gradient 3) Species niche