1) This document discusses peatland management in the UK and its impacts on carbon storage and climate regulation. It provides details on the spatial extent of peat soils and peatland management/condition across the UK. 2) Meta-analyses of existing studies and emissions factors derived from modeling are used to assess the likelihood that different peatland management interventions will result in greenhouse gas benefits. 3) Ongoing work includes modeling the climate resilience of peatland management approaches, accounting for climate change impacts on emissions factors, and measuring emissions from a range of lowland peatland sites under different management conditions.

1. PEATLAND MANAGEMENT
IMPACTS ON
CARBON/CLIMATE
REGULATION - UK EVIDENCE,
SPATIAL CONFIGURATION OF
STOCKS AND PRESSURES
Fred Worrall,
Department of Earth Sciences,
Durham University

2. The approach I have taken to this problem
UK evidence
JNCC report – other reports are also available
Meta-analysis – how much evidence do we have?
Derivation of emissions factors
Spatial configuration
Spatial extent of peat soils – stocks
Spatial extent of peat management/condition
Ongoing developments

3. Spatial extent of peat soils
Country Peat type sub-type Area of peat
(km2)
England Deep peat Total 6799a
Lowland wasted 1922
peatb
Upland peat 3553
Raised bog 357
Lowland fen 958
Other 9
Shallow peats 5272
Soils with 2114
scattered
pockets of
deep peat
Scotlandd Total deep peat 17269
Wales Deep peats 706
Total peaty 2809
soils
Northern Deep peats 1700c
Worrall et al. (2011).
Ireland
UK Intact deep total 17125 JNCC Report 442
peat

4. Spatial extent of peat soils
We have soil maps for
each part of UK
But for stocks assessment
level of detail can vary
Information on
depth/density/carbon
content is rare
Some specific studies of
certain areas (Exmoor,
North Pennines)

5. Spatial extent of peat management/condition
Burning
Bare soil
This level of spatial information is not available UK-wide.

6. Emissions factors
Meta-analysis
What is the probability that intervention will result in a
GHG benefit?
What is the equivalent number of studies do we have?
Bayesian framework means that it is updatable
Emission factors
Default values – Couwenberg et al (2008) or Bryne et
al. (2004)
Values from UK field studies
Values from computer modelling

7. Summary of JNCC meta-analysis
Management Likely spatial Probability of Effective sample Existing study site
extent improvement size (GHG)
Afforestation 5 2 
Deforestation ? 2 
Drainage 3 4 
Drain-blocking ? 3 
Grazing removal 1 1 
Managed burning 4 
Revegetation 2 4 5 
Restoration of cutover 5 1 
peatland
Converted for 3 ? ? 
agriculture

8. Emission factors from computer modelling
Management From modelling
(tonnes C ha yr -
Only an example of
1)
the information in the
Afforestation Peat soil +1.94a
Above -3.87 JNCC report
ground
biomassb This can include
Deforestation - interactions between
Drainage Average -0.05
Grazing +0.1 managements
present
Grazing -0.01
not present
Burning +0.2
present
Burning not -0.06
present

9. Minimum input requirement approaches
Run models with and
without a management
intervention
Run models across the
range of locations for
which we have inputs
Over 4000 model runs
Use statistical
approaches to find the
important drivers
2
CTotal 0.087 A 1.7 f peat 210 f baresoil 138.5 r 96 %, n 474

10. Summary
UK evidence
We know the quality of our emissions factor data
Our biggest source is lowland peat
Spatial configuration
Spatial extent of peat soils
Good but lacks supporting data to give stocks value
Spatial extent of peat management/conditions
good enough in places

11. The Durham Carbon Model already includes …
Drains
Gullies
Bare soil & revegetation
burning Cutting

12. The Durham Carbon Model now includes …
Heather Grasses
Mosses
Forest Sedge

13. Modelling climate resilience
1
Relative sink size compared to present
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
No action Block all Revegetate Cease grazing Cease burning Targeted best
drains possible action
Which interventions now would provide the most protection in the
future?
Projecting management interventions into the future under climate
change scenarios.
We could correct Efs for climate change

14. New Defra project – GHG emissions from lowland peat
New large scale project
measuing emissions from a
range of lowland sites
under a range of
managements
Managements include –
fens, arable, dugover/bare
peat, restored, pasture
4 major sites with several
secondary sites