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Page 1: GEST Model – vegetation proxy for GHG flux from peatlands

GEST Greenhouse Emissions Site Types

• The ‘emissions avoided’ model developed by John Couwenberg et al. at University of Greifswald.

• Couwenberg et al., 2011, Hydrobiologia.

Page 2: GEST Model – vegetation proxy for GHG flux from peatlands

Using a Proxy for GHG fluxes

• Direct methods

– chamber measurements –

– Micro-meteorology measurements–

• Indirect method

– Use a proxy that indicates ghg fluxes

Page 3: GEST Model – vegetation proxy for GHG flux from peatlands

Three parameters currently emerge as suitable proxies for GHG

fluxes from peat soils:

• Subsidence

• Water level

• Vegetation

Possible Proxies

Page 4: GEST Model – vegetation proxy for GHG flux from peatlands

Subsidence

Su

bis

den

ce (

cma-1

)

Drainage depth (cm)

CONS:

1. hardly covertable into CO2 emission, due

to shrinkage and compaction

2. not an indicator for N2O and CH4

3. only for drained situations

Page 5: GEST Model – vegetation proxy for GHG flux from peatlands

Water table depth

Carbon dioxide O - flooded site & lysimeter experiments of Mundel (1976)

• - based on long term

subsidence measurements (van den Akker et al., 2008;

Verhagen et al., 2009) • -

representing NEP measurements corr. for harvest export (Augustin unpubl., Bortoluzzi et al. 2006, Drösler 2005, Flessa et al. 1998, Jacobs et al. 2003, Meyer 1999, Müller et al. 1997, Mundel 1976, Nieveen et al. 1998, Veenendaal et al. 2007.

Methane

n = 99 - collated from Augustin (2003, unpubl.), Augustin & Merbach (1998), Augustin et al. (1996), Bortoluzzi et al. (2006), Drösler (2005), Hendriks et al. (2007), Jacobs et al. (2003), Meyer (1999), Müller (1999), Sommer et al. (2003), Tauchnitz et al. (2008), Van den Bos (2003), Van den Pol-Van Dasselaar et al. (1999), Van Huissteden et al. (2006), Von Arnold (2004), Wild et al. (2001).

CONS:

1. mapping of water level via remote sensing

is so far impossible

2. direct monitoring is very labour-intensive

Page 6: GEST Model – vegetation proxy for GHG flux from peatlands

Vegetation Emissions strongly related to water level

and

Vegetation can be strongly related to water level –e.g. Ellenberg moisture

values

Page 7: GEST Model – vegetation proxy for GHG flux from peatlands

- Species groups presence/absence as indicator for mean water levels

- Initially NE German metadata, country-specific refinement in Belarus &

Ukraine peatlands

site factor gradient - moisture

species groups

Moisture classes

subunits 1

1 2

2

3 4 5

1 2

Page 8: GEST Model – vegetation proxy for GHG flux from peatlands

A simpe GEST example

Re-wetting Bog

green Sphagnum

lawn (optimal)

Sphagnum

Eriophorum lawn

acidophilous

Molinia-meadow

Vegetation

+10 … -10+10 … -20-15 … -45water level*

GWP

CO2

CH4

GEST

3-1.516.5

-2-215

50.51.5

wet peatmoss

lawn

very moist

peatmoss lawn

moist forbs &

meadows

green Sphagnum

lawn (optimal)

Sphagnum

Eriophorum lawn

acidophilous

Molinia-meadow

Vegetation

+10 … -10+10 … -20-15 … -45water level*

GWP

CO2

CH4

GEST

3-1.516.5

-2-215

50.51.5

wet peatmoss

lawn

very moist

peatmoss lawn

moist forbs &

meadows

-13.5t CO2-eq.·ha-1·a-1

*median of the dry and wet season relative to the surface, cm

Page 9: GEST Model – vegetation proxy for GHG flux from peatlands

Moderately dry

cultivated

peatland

24

Very moist

reeds and Wet

reed/sedge fens

Very moist

reeds and Wet

reeds/sedge

fens

Rewetting open fen Future emissions avoided

Year 0 Year 10 Year 20

Moderately dry

cultivated

peatland

24

Moderately dry

cultivated peatland

24

Very moist reeds/

Wet reeds & sedge

fens

15.5/8.5

Moderately dry

cultivated

peatland

24

Bas

elin

e S

cen

ario

R

ewet

tin

g Sc

en

ario

Very moist reeds/

Wet reeds & sedge

fens

15.5/8.5

Moderately dry

cultivated

peatland

24

8.5/-15,5 -8.5/-15.5

Page 10: GEST Model – vegetation proxy for GHG flux from peatlands

Metadata Indicator

species/communities with water table depth

Initial values for avoided emissions

= Baseline - Project

Local refinement Measuring

Species/communities Water depth

Final value for avoided emissions

Emissions accounting mechanisms, auditing

etc


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