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Challenges and options
John Couwenberg
Hans Joosten
Greifswald University
Are emission reductions from peatlands MRV-able
Stocks & emissions
Current Carbon stock in peat soils:
~550 000 Mt C
Current emissions from drained peatlands:
>2000 Mt CO2 y-1
Global CO2 emissions from drained peatlands
Drained area
(106 ha)
CO2
(ton ha-1 y-1)
Total CO2
(Mton y-1)
Drained peatlands in SE Asia 12 50 600
Peatland fires in SE Asia 400
Peatland agriculture outside SE Asia 30 25 750
Urbanisation, infrastructure 5 30 150
Peat extraction 30 1 60
Boreal peatland forestry 12 1 12
Temperate/tropical peatland forestry 3.5 30 105
Total 63 2077
Mitigation management options
• Conservation of the C stock • Sequestration of C from the atmosphere• Substitution of fossil materials by biomass.
Conservation management
Conserve existing peat C pools:• Prevent drainage• Reverse drainage by rewetting
yearly emissions
time
Reducing the rate of peatland drainage(rate of reclamation of new areas)
Peatlands continue emiting for decades after drainage:Annual emissions are cumulative
Conservation management
Rewetting is the only option to reduce emissions
Strategic rewetting of 30% (20 Mio ha) of the world’s drained peatlands could lead to an annual emission avoidance of almost 1000 Mtons CO2 per year.
Sequestration management
• ~75% of peatlands are still pristine• accumulating new peat • removing & sequestering 200 Mtons CO2 y-1
strict protection
• rewet 20 Mio ha• restore peat accumulation in 10 Mio ha
additional removal ~10 Mtons CO2 y-1
Substitution management
• replacing fossil resources by biomass from drained peatlands:
CO2 emitted > CO2 avoided
• biomass from wet peatlands orpaludiculture (= wet agriculture and forestry)
• implemented on 10 Mio ha of rewetted peatland substitution of 100 Mtons of CO2
Peatland management
• avoiding peatland degradation and • actively restoring peatlands• results in significant climate benefits
quantify emission reductions
Proxies: water level
-120-100-80-60-40-200
mean annual water level [cm]
t CO2 ha-1 y-1
0
10
20
30
40
50
Good proxy for CO2 emissions:Example temperate Europe
Proxies: water level
-100
0
100
200
300
400
500
600
-100 -80 -60 -40 -20 0 20 40 60
mean water level [cm]
kg C
H4?
ha-1
y-1
-2
0
2
4
6
8
10
12
t C
O2-e
q?
ha-1
y-1
Good proxy for CH4 emissions:Example temperate Europe
-0,5
0
1
2
3
CH4 emission [mg m-2 h-1]
0
5
10
15
-100 -80 -60 -40 -20 0 20water level [cm]
Proxies: water levelGood proxy for CH4 emissions:
Boreal/tempEurope
SEAsia
At high water levelsdifferences due tovegetation
Emissions strongly related to water level
Vegetation strongly related to water level
Use vegetation as indicator for emissions
Proxies: vegetation
• developed for NE Germany• currently being verified, calibrated and updated
for major peatland rewetting projects in Belarus.
Proxies: vegetation
Advantages of using vegetation • reflects longer-term water level conditions • reflects factors that determine GHG emissions
(nutrient availability, acidity, land use…),• itself determines GHG emissions
(quality of OM, aerenchyma mediated CH4)
• allows fine-scaled mapping (1:2,500 – 1:10,000)
Proxies: vegetation
Disadvantage of using vegetation • slow reaction on environmental changes• necessity to calibrate for different climatic and
phytogeographical conditions.
GESTs with indicator species groups
GEST: moderately moist forbs & meadows
Vegetation forms:Urtica-Phragmites reedsAcidophilous Molinia meadowDianthus superbus-Molinia meadow…
Each with typical / differentiating species
Each GEST with GWP
Proxies: subsidence
• loss of peatland height due to oxidation
• complication: consolidation, shrinkage
• promising especially in the tropics:subsidence based methodology being developed by the Australian-Indonesia Kalimantan Forests Carbon Partnership.
Proxies: subsidence
0
1
2
3
4
5
6
7
-120 -100 -80 -60 -20 0
subsidence [cm y-1]
0
Estimated emission [t CO 2 ha-1 y-1 ]
8
9
10
10
20
30
40
50
60
70
80
90
-40
drainage depth [cm]
Oxidative componentderived from changesin bulk density andash content:
Proxies: subsidence
• possible to measure using remote sensing and ground-truthing
• works well for losses from drained peatlands, but less for decrease in losses under rewetting (swelling)
Monitoring emission reductionsfrom rewetting and conservation
• wide range of land use categories
• may require different approaches to– reduction of GHG emissions – monitoring these reductions
• land use may enhance GHG emissions(plowing, fertilization, tree removal)
Monitoring emission reductionsfrom rewetting and conservation
Avoided emissions need clear baseline
• clear in case of rewetting
• proxy approach for avoided drainage– Note: peat depth determines duration of
possible emissions after drainage
Monitoring emission reductionsfrom rewetting and conservation
• cost of monitoring is related to the desired precision of the GHG flux estimates.
• determined by market value of ‘carbon’
• assessing the GHG effect of peatland rewetting by comprehensive, direct flux measurements might currently cost in the order of magnitude of € 10 000 ha-1 y-1
Monitoring by proxies
Monitoring GHG fluxes using water levels:
• data frequent in time, dense in space. field observations and automatic loggers.
• water level modelling based on weather data
• remote sensing not yet suited
Monitoring by proxies
Monitoring GHG fluxes using Vegetation:
• easily mapped and monitored in the field
• monitoring by remote sensing has been tested successfully and is very promising, also in financial terms.
Monitoring by proxies
Monitoring GHG fluxes using subsidence:
• easily monitored by field observations, but practically impossible over large areas when annual losses are high.
• In tropical peatlands (several cm y-1) the use of LiDAR looks very promising.