Peatlands and Greenhouse Gas Emissions

Mark Cooper, Chris Evans, Piotr Zielinski, Tim Jones, Annette Burden, Mike Peacock,

Chris Freeman, Mike Billett, Nick Ostle, Pete Levy, Kerry Dinsmore, et al.

Talk Structure• CEH Carbon Catchment Project• Effects of drainage ditch blocking• Effects of atmospheric deposition

Acknowledging CEH, WCCL and Bangor University

UK Soil C

Auchencorth Moss

Moor House

Forsinard

Upper Conwy

CEH ‘Carbon Catchments’

• Ecosystem carbon balance being measured at four peat catchments (land-atmosphere and dissolved C fluxes)

• Experimental components:– Drained/undrained (Forsinard)– Burnt/unburnt (Moor House)– High/low nitrogen deposition (Auchencorth)– High/low acid deposition (Conwy)

DOC input in precipitation

Evasion of CO2 and CH4 from stream surface

Downstream export of DOC, DIC, POC, CO2, CH4

Land surface exchange of CO2 and CH4

Floating chambers or tracer gas injections

Outlet measurement station: discharge and aquatic C concentrations

Array of static chambers Eddy covariance

measurement system (flux footprint)

Peat cores for measuring C accumulation rate

Gas exchange from bog-pool system

Carbon CatchmentsBaseline monitoring

Migneint

Moor House

Auchencorth

Forsinard

CARBONBALANCE

CO2 Exchange Methane

Dissolved

Gases

Dissolved

Carbon

Main Peatland Carbon Fluxes

Site Net CO2 exchange

CH4 DIC DOC POCNet C balance

Mer Bleue, Quebec1 -40 4 15 -22

Degerö Stormyr, N. Sweden2 -51 11 4 13 -23

Glencar, SW Ireland7,8 -55 5 15

Auchencorth, E. Scotland3,4 -115 <1 15* 25 4 -70

Moor House, N. England

-20 7 10 23 18 +38

Migneint, N. Wales

5 1 19 1

Carbon Catchment: Nant Y Brwyn

• Upland Blanket bog which forms part of the Migneint • Nant Y Brwyn is approx 1.68km2

• Mean annual rainfall is approximately 2200 mm yr–1

• Mean annual temperature is 5.6°C• Main vegetation consists of Calluna, Juncus,

Sphagnum, Eriophorum• Light grazing between May and October

Carbon Catchment: Nant Y Brwyn• Flux Tower• Automated Weather Station• Static Gas Chamber sampling• Automated River Monitoring• Complete carbon budget is still

a working progress

Methane

Landscape Scale

• Aerial Photography• Field Surveys• High Resolution LiDAR

Nant Y BrwynEstimated Habitat Coverage (%)

Riparian Juncus FlushUndrained Cal-luna HeathSphagnum GullyUpland Juncus FlushAcid Grassland

Riparian Juncus flush covers 12% & contributes 87% of the overall CH4 budget

Riparian Juncus Flush 86.97%

Undrained Calluna Heath 7.30%

Sphagnum Gully 3.91%

Upland Juncus Flush 1.08%

Acid Grassland 0.74%

Contribution to Landscape CH4 Budget

Llyn Serw, Migneint

• Conwy, North Wales• Habitat – wet Calluna heath on Blanket Peat

– NVC M19 – Calluna, Eriophorum sp., Sphagnum sp.

• Historical Drainage with ditches– 1920’s & 1930’s running S-SE (mostly re-vegetated)

– 1970’s & 1980’s running N-S• NT blocked ditches in pilot study in 2008

National Trust peat restoration pilot study, Llyn Serw

CH4CH4

CO2CO2

CH4CH4

CO2CO2

CO2CO2

Transect of trace Gas Measurements

A DCB E F A DCB E F

Dip wellGas Measurement

Transect Code

Gas Measurements - between 11am – 3pm

Before:

After:

Two years after:

Results Summary

• Infilled ditches contribute a significant percentage to landscape scale methane budget despite occupying a tiny percentage of the landscape

• Compensating increase in CO2 sequestration not yet quantified

• Vegetation in ditch is critically important for CH4 flux

• Is this a transient or a long-term effect?

Defra project to assess the impacts of peat restoration on the GHG balance

• Five year field experiment to evaluate the effects of peat restoration on methane emissions and the overall C and GHG balance (with Leeds and Open Universities, National Trust)

• Replicated study of 12 ditches, with 2 ditch-blocking treatments, pre- and post treatment measurements (CH4, CO2, DOC, discharge, etc)

Many thanks

marope@ceh.ac.uk

I am expecting to finish my PhD 2011/2012.