PEATLAND MANAGEMENT

IMPACTS ON

CARBON/CLIMATE

REGULATION - UK EVIDENCE,

SPATIAL CONFIGURATION OF

STOCKS AND PRESSURES

Fred Worrall,

Department of Earth Sciences,

Durham University

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

Spatial extent of peat soils

Country Peat type sub-type Area of peat

(km2)

England Deep peat Total 6799a

Lowland wasted

peatb

1922

Upland peat 3553

Raised bog 357

Lowland fen 958

Other 9

Shallow peats 5272

Soils with

scattered

pockets of

deep peat

2114

Scotlandd Total deep peat 17269

Wales Deep peats 706

Total peaty

soils

2809

Northern

Ireland

Deep peats 1700c

UK Intact deep

peat

total 17125

Worrall et al. (2011).

JNCC Report 442

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)

Spatial extent of peat management/condition

This level of spatial information is not available UK-wide.

Burning

Bare soil

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

Summary of JNCC meta-analysis

Management Likely spatial

extent

Probability of

improvement

Effective sample

size (GHG)

Existing study site

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

peatland

5 1

Converted for

agriculture

3 ? ?

Emission factors from computer modelling

Only an example of

the information in the

JNCC report

This can include

interactions between

managements

Management From modelling

(tonnes C ha yr-

1)

Afforestation Peat soil +1.94a

Above

ground

biomassb

-3.87

Deforestation -

Drainage Average -0.05

Grazing

present

+0.1

Grazing

not present

-0.01

Burning

present

+0.2

Burning not

present

-0.06

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

474%,965.1382107.1087.0 2 nrffAC soilbarepeatTotal

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

The Durham Carbon Model already includes …

Bare soil & revegetation

Drains

Cutting burning

Gullies

The Durham Carbon Model now includes …

Heather Grasses

Mosses

Forest Sedge

Modelling climate resilience

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

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

No action Block all drains

Revegetate Cease grazing Cease burning Targeted best possible action

Rela

tive s

ink s

ize c

om

pare

d to p

rese

nt

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