Eco-Efficient Living: Redefining Sustainability through Leech's Green Design ...
Peatland Rewetting in the South West
1. Peatland Restoration in
South West England
ALA South West Regional Meeting
26th February 2013
Dr. David Smith – South West Water and
Exmoor Mires Project Manager
5. Exmoor peatlands have become
largely dry and dominated by
Molinia (sedge grass) as a result
6. Exmoor Mires Project
• Initiated in 1998 by ENPA, EA and NE. First
restoration work at Exe-head in 2001-4
aimed to benefit the River Exe.
• New Partnership for 2006-9 project included
SWW and Wildlife restoration was the main
funding aim.
• 2010-15 SWW customers funded project for
water supply, quality and wildlife.
7. What has the project achieved?
• The blocking of 50km of ditch and the re-
wetting of 400ha of mire at 20 locations
14. Current Exmoor Project 2010- 15
• £2m budget for Exmoor
• 2000ha target restoration area
• 2800ha of peatland has been surveyed, the
ditches/peat-cuttings measured and GPS
mapped and the restoration potential
assessed.
• Restoration has been identified as possible
on 2000ha.
• Restoration carried out on over 100ha so far
18. Proof of Concept monitoring
Plant monitoring has found an
increase in Sphagnum species and less
Molinia
19. Other Wildlife monitoring (Birds,
dragonflies, amphibians, reptiles, etc)
Dragonflies example is typical of increases;
Black Darter- (rare on Exmoor as it needs
bog pools) Blackpitts now has possibly
the largest population in Somerset (100’s
seen in 2011)
Common Hawker-(rare in southern
England) x10 seen at Blackpitts and x2 at
Squallacombe in 2012
20. Agricultural Impact of Mire
restoration monitoring
• base line survey started this year by WRT,
• post-restoration surveys in subsequent
years.
21. Hydrological Monitoring:
Water storage and quality changes
•Monitoring Equipment per site:
54 dipwells, 18 temperature loggers, 60
capacitance probes, 30 mini conductivity
loggers, 3 seepage meters.
22. Monitoring GHG flux and storage
Internal balloon (to dampen
pressure changes)
Vent Tube
Lid &
chamber
Fan to mix
chamber air
Sample
Chamber,
Outlet
lid and Temperature and
collar are relative humidity
sealed logger
using a Ground Collars
water-filled
groove
23. Why Monitor?
• Need to prove to the Water Regulator
that peatland restoration achieves its
aims of improving water supply and
quality.
• The outcome information is also needed
for the set-up of a revenue payment for
Mire restoration.
Editor's Notes
1. Gas fluxes are measured from the surface of the peatlands using closed chambers. 2. Each site is fitted with permanent ground collars onto which the chamber is placed during gas collection. 3. The chamber is sealed with a gas-tight lid. 4. Gas samples are collected over a 15-min period every 5 minutes and the change of concentration with time of the gas species is used to determine their flux rate (taking into account chamber volume, internal temperature and the foot print of the chamber). 5. A balloon on the inside on the chamber is connected to the external air. It helps dampen any sudden pressure changes that might trigger ebullition events (i.e., sporadic bubble release from the soil). 6. The vent tube allows outside air to enter the chamber at the same rate that it is being withdrawn during sample collection. The total volume of each sample is ~60 ml (1 x 20 ml sample + duplicate flushing). The amount of ‘fresh’ air entering the chamber is taking into account in the flux data processing (i.e., as a dilution). The vent tube prevent negative pressure from forming in the chamber which could trigger or enhance the rate of gas release from soil.