Threat of (peaty-)wetlands

Land use (wetland crop fields/meadow)Commercial use (peat-mining)

+ global warming

Open water after peat-mining

Miner

Function: deposits of un-dissolved plants

Biological supporting diversity (endangered species) and ecosystem carbon sink

Physical Chemical

Causes of decreasing

Cool temperate regions, including Hokkaido

Lost function

Soil typeOrganism Environment

Environment (Soil)

S = f(Cl, O, r, p, t, ···)S: soilCl: climateO: organismsr: relicp: parent materialt: time

Soil formation processes

WeatheringMechanical weatheringChemical weatheringBiological weathering

Migration / TransportationSedimentation

Particle sedimentation

Organic-matter accumulation

LeafLitterDuffSoil

Based on geographical characteristics and water status, this type is subdivided into BA, BB, BC, BD, BD(d), BE, and BF from dry to wet sites. BD (mesic

brown forest soil) is a representative.

Soil profile observed in Fagus crenata forest on the mid-slope of Mt. Hidehiko with 1075 m in altitude, Fukuoka Pref., Kyushu, Japan. (Sept. 18, 1997)

F-HA1

A2

A-B

B

B2

Acidic brown forest soil: Widely distributed in temperate-warm montane zones

Biei Town, Kamikawa DistrictCommon type in the forests of Japan, including Hokkaido

A layer

B layer

Fine-textured acidic brown forest soil

Andosol: origin = volcanic deposits, rich in humus (Left: Akasaka, Hakodate City, Crop field, 1991. Right: Shibetsu Town, Nemuro District, 1994; multi-layer volcanic deposits)

Physical properties are fine, but phosphorus fixation is strong. This means minute nutrients are often deficient. This type is common at Nemuro and Kushiro Districts in Hokkaido.

loamy humus

volcanic ash(35000-45000 yr) Ten layers of volcanic deposits

Top: 500-1900 yrBottom: 6500-7200 yr

Pseudo-gley soilForest in Takikawa City, Sorachi District (1990)

> 125 cm: gley layer

(Lowland) Gley soil is often located close to peatlandsNamporo Town, Sorachi District (1989)

This photo indicates a typical gley soil

Podozol

In Japan, podozol is distributed only in northern Hokkaido.

Profile

the typical soils of coniferous, or boreal forests, and also of eucalypt forests and heathland

characterized by the ash-colored layer, developed by bleaching

nutrient-poor

Distribution of soil types

Brown forest soil

Andosol

Gley soil Peat soil

River

Water movement

Soil conservationProtection of land degradationErosion control

Disturbance

Fig. 4.2 Biomass decreases with disturbance. The disturbances are fire (annual burning), herbivory (mainly grazing by nutria), and a single or double application of herbicide (Keddy et al. 2007)

Disturbance type

Control Fire Herbivory Single Double

750

500

250

0

Bio

mas

s (g

/m2 )

Four properties Duration Intensity (magnitude) Frequency (interval) Scale (area)

Flooding

Stabilizing water levels compress wetlands from four zones (left) to two zones (right) (Keddy 1991)

aquatic

shrub

shrub

aquatic

wet meadow

marsh

Amplitude of long-term water level fluctuations

Disturbance-maintained ecosystems or landscapes

Fig. 1.11 The principal kinds of wetlands can be related to duration and depth of flooding. These two axes are important because they give rise to the secondary constraints

Depth of floodingshallow deep

Du

rati

on o

f fl

ood

ing

con

tin

uou

sin

term

itte

nt

peatland(bog or fen)

aquatic

marsh

wet meadow

swamp

(Keddy 2010)

Swamp developed by flooding

Flooding produces the characteristic vegetation types in extensive upper Nile swamps (Thompson 1985)

Najas pectinata

Eichhornia crassipes

Typha domingensis

Vossla cuspidata

Phragmites karka

Cyperus papyrus

Trapa natans

Nymphaea lotus

Oryza longistaminata

Hyparrhenia rufaEchinochloa

pyramidalls

Rain-fad grassland (flooded in exceptional years)

Seasonal swamp (3-4 months submerged, to 3-4 weeks submerged

Permanent swamp with perennial pools

Fringe vegetation (deep-rooted, shallow-rooted, and floating ‘sudd’

Submerged and free-floating vegetation

Floodplain

Flooding along with sediment erosion and deposition, produces the characteristic vegetation types of the Lower Nile floodplain (Springuel 1990)

Typha domingensis

Acacia

Halfa grass

Tamarix niloticaGrass +

herbs

Polygonum senegalense

Phragmites australis

Acacia albida

Dom palm

Nubia sandstone

Silt

Water

Lawsonia inermis

sand

Habitat types

Formation

Floodplain

Swamp

Slope of 2nd

terraceThom bush

1st terrace

Meadow

2nd terrace

Riverain woodland

Tussock

Sarobetsu mire:Carex middendorffiiEriophorum vaginatum

Hokkaido: Carex limosa, Carex cespitosa, Carex thunbergii, and others

Tussock wetland (Sarobetsu)

Eriophorum vaginatum

Carex middendorffii

Center

Flat

EdgeSeed trap

Fig. 3. Relationship between tussock height and number of species occurring on tussocks of Carex meyeriana in a marshland in China. (Tsuyuzaki & Tsujii 1992)

Height (cm)0 10 20

Nu

mb

er o

f sp

ecie

s

6

5

4

3

2

1

0

y = +0.712x + 0.261r = +0.702P < 0.01

Table 1. Frequency of species (%) occurring on tussocks of Carex meyeriana (Tsuyuzaki & Tsujii 1992)

**: Significantly different at P < 0.001, *: P < 0.01, ns: not significant.

Height of tussocks (cm)

4-11 12-16 17-26 All

(n = 19) (n = 20) (n = 17) (n = 56) c2

Species

Equisetum limosum 84.2 95.0 94.1 91.1 0.8 ns

Potentilla anserina 5.3 35.0 52.9 30.4 37.2**

Chamaesium paradoxum 0 30.0 23.5 17.9 27.9*

Potamogeton sp. 0 5.0 35.3 12.5 54.3*

Poa chalarantha 0 5.0 23.5 8.9 32.3*

Ranunculus pedicularis 0 10.0 11.8 7.1 11.1*

Triglochin maritimum 0 5.0 5.9 3.6 5.6 ns

泥炭採掘跡地に見られるワタスゲなどの谷地坊主

facilitation

Tussock Solidago

Loberia

Moliniopsis　　　Drosera

Hypochaeris

(Koyama & Tsuyuzaki 2010)

0

1

0

1

0

1

0 2 4 6 8 10(m )

Stability ↑(Structure)

temperature fluctuation ↓(litter)

strong light ↓(litter)

Distribution of seedlings

Individual-based monitoring

The area of each microhabitat is shown in parenthesesThe total number of individuals on Phragmites australis, of which seeds were captured by seed traps, was 223 and most of them were established in the flat, although the microhabitats were not recordeda The individuals of R. alba were not counted when the turfs were developed. R. alba turf cover was less than 0.1% in total, 0.02 m2 at the edge; 0.07 m2 on the flat, and zero at the centerb Indicate that seed traps captured the seeds

Table 1 Total number of individuals with reference to three microhabitats (center, edge and flat) on six 1 × 10 m plots established in post-mined peatland, Sarobetsu mire, from September 2005 to September 2006

(Koyama & Tsuyuzaki 2010)

Species a

Hypochaeris radicataDrosera rotundifolia Solidago virgaureaMoliniopsis japonica Carex middendorffiiLobelia sessilifoliaEriophorum vaginatumHydrangea paniculataSanguisorba tenuifolia

Seeddispersal

Wind b

Wind b

Wind b

Wind b

Gravity b

Gravity/Wind b

Wind b

GravityWind

Center(2.3 m2)

50600

13001

Edge(8.3 m2)

8711742219966

134707821

Flat(49.4 m2)

54227817527016380782341

Total(60.0 m2)

1,41845240236922922714810163

(Koyama & Tsuyuzaki 2010)

Table 2. Estimated effects of microhabitat on distribution, survival, growth and flowering for common species

D. rotundifoliaH. radicataL. sessilifoliaM. japonicaS. virgaurea

Center (top)Carexmiddendorffii

Eriophorumvaginatum

EdgeCarexmiddendorffii

S F J Wt Fl F G JSJ Fl

Eriophorumvaginatum

SJSJ Wt

SJ

Flat

Survival in Wt: winter Sm: in summer

G: growth (RGR)Fl: flowering

The species traits increased or enhanced (= positive effects) by the microhabitats are shown.

Number of S: seeding J: juvenile F: fertile

The functions of tussocks are not greatly different between the two species

⇒ What factors facilitate the establishment of cohabitants

(Koyama & Tsuyuzaki 2010)

Fig. 2 a Seasonal fluctuations of seeddispersal and seedling emergence on common species from June to October 2006. Number of seedlings emerged in six 1 × 10 m plots and number of seeds captured by 294 seed traps are shown. b Number of seeds (mean ± SE) captured by seed traps on three microhabitats (center, edge and flat). Mean number of seed traps is shown in parentheses. The best clusters determined by AIC model selection are shown by angled brackets and model codes 1–3. Each numeral above bracket indicates the coefficient of difference in number of seeds from flat to other microhabitat(s), confirmed by GLM when models 2 and 3 are adapted. ** P < 0.01, * P < 0.05, ns P > 0.05

Seed trap effect on the edge

(Koyama & Tsuyuzaki 2012)

Fig 1. Three microhabitat types (flat, tussock edge, and tussock mound) on and around tussocks. The rhomboids show seed-sowing plots established on each microhabitat.

Objectives:Clarifying differences in the effects of litter and shape of tussocks on cohabitantsMethods:Artificial removal of litter → seed-sowing and transplantation experiments

(Moliniopsis japonica and Lobelia sessilifolia)

(Koyama & Tsuyuzaki 2012)

Fig. 2 Differences among five microhabitat types (Car, Carex; Eri, Eriophorum) in a mean daily maximum PPFD (mmol m-2 s-1), b mean water content (%) in peat, and c, d seed retention (%) of M. japonica and L. sessilifolia. Box-and-whisker plots indicate 75th, 50th, and 25th percentiles; the top whisker ranging from the 75th to 90th percentile, and the bottom from the 25th to 10th percentile. The different letters indicate significant differences between the microhabitat types (Tukey’s HSD test, P < 0.05)

litter

mound

mound

mound