Gully blocking & revegetation:Exploring the evidence

Mark Reed, Jim Rouquette and Dylan Young

1 Introduction

Purpose

• Explore evidence re: effects of undertaking Peatland Code projects on different ecosystem services

• Stimulate discussion and inform decisions about what might be a fair price to charge for undertaking Peatland Code projects

Types of peatland condition addressed by Peatland Code (and this talk):

2 Changes in ecosystem services(based on perceptions of previous workshop participants)

Increase drink water qual

Peat in carbon code

WFD

Safeguard zones

Decreased AE payments

More droughts

More storm events

Increased wildfire

-20 -15 -10 -5 0 5 10 15 20

Agricultural produce

Wild produce

Water provision

Climate regulation

Natural hazard regula-tion

Water purification

Erosion prevention

Recreation and tourism

Aesthetic value

Intellectual, scientific etc.

Provision of habitat

Cumulative indicator score

Impact on most important ecosystem services

Agricultural produceWild produce

Fibre and fuel

Water provision

Genetic resources

Biochemicals etc.

Ornamental resources

Energy harvesting

Air quality regulation

Climate regulation

Natural hazard regulation

Water purificationErosion preventionPollination

Pest and disease control

Noise and light regulation

Recreation and tourism

Aesthetic value

Inspiration

Intellectual, scientific etc.

Spiritual, ethical, religious

Cultural heritage

Social relations

Provision of habitat

-3.0

2.0

7.0

Adoption of peat in carbon code

Predicted impact of adopting peat in carbon code on ecosystem services

3 Effects of gully blocking & revegetation(based on perceptions of previous workshop participants)

Managed burning

Grouse numbers

Stream ecology

Heather cover

Water Framework

Directive

Sphagnum cover

Water storage

Depth of peat

Extent of gulleying

Water- table

Wildlifeabundance

Peat accumulatio

n

Water movement

Palatable grasses

Vegetation diversity

Erosion

Gulley blocking

Water quality

Bare peat

Access

Drainage

Increase

Decrease

A little

Some

A lot

Relationships related to managed burning and gulley blocking

Note: preliminary data. Direct relationships

Heather cutting

Managed burning

Grouse numbers

Stream ecology

Heather cover

Water Framework

Directive

Sphagnum cover

Water storage

Depth of peat

Extent of gulleying

Water- table

Wildlifeabundance

Peat accumulatio

n

Water movement

Palatable grasses

Vegetation diversity

Erosion

Gulley blocking

Water quality

Bare peat

Access

Drainage

Increase

Decrease

A little

Some

A lot

Relationships related to managed burning and gulley blocking

Note: preliminary data. Including indirect strong relationships.

Heather cutting

Pipe networks

4 Other evidence(based on published literature)

A brief overview

Based on:• Recent evidence reviews: IUCN Commission of

Inquiry; Natural England Upland Evidence Review• Peak District projects: Defra’s Ecosystem Services of

Peat project; Sustainable Uplands project; Making Space for Water

• Other peer-reviewed sources of evidence

A brief overview

Evidence for effects of peatland restoration on ecosystem services• Greenhouse Gas emissions• Water• Biodiversity• Other benefits

Note: contested evidence over effects of burning

Burning

Greenhouse Gas Emissions

Bare soil & revegetation Drains

Cutting

Gullies

Courtesy of Fred Worrall, University of Durham

Greenhouse Gas Emissions

Heather Grasses Mosses

Forest

Sedge

Courtesy of Fred Worrall, University of Durham

Greenhouse Gas Emissions

Current GHG emissions 2030 emissions with- 2030 emissions without grazing/burning targeted burning/grazingcessation, gully blocking and revegetation

Reed et al. (2013) Anticipating and managing future trade-offs and complementarities between ecosystem services. Ecology & Society 18(1): 5 http://dx.doi.org/10.5751/ES-04924-180105

Greenhouse Gas Emissions

Greenhouse Gas Emissions

Take home message:• Look over appropriate time-horizons• Targeted action, following best practice – different

measures in different places

Water

• Gully block/revegetation reduces sediment production and loss of Particulate Organic Carbon

• Reduces export of heavy metals• Evidence for reduction in Dissolved Organic Carbon is

patchy/contradictory– Data collection too

site-specific and

short-term

Courtesy of Mike Billet, Centre for Ecology & Hydrology

Water

Revegetation slows rate at which water runs off and reduces flood peaks

0.001

0.01

0.1

1

0.001 0.01 0.1

depth, m

velo

city

, m .

s-1

UnvegetatedEriophorumSphagnum

Holden et al (2008) Water Resources Research

Green = Bare peat

Red = Sphagnum

Water

Gully blocking may reduce or increase flood peaks

Biodiversity

• Depends what “bit” of biodiversity you’re

interested in• Healthy bogs support a

range of important bird, plant and moss

species• Both intensifying and extensifying management is

likely to be bad for biodiversity – need a healthy balance, which includes active management

Other benefits

• Accessibility and aesthetic benefits of blocking gullies and revegetating bare and eroding peat for recreation/tourism

• Protecting archaeological artefacts

Bronze age axe found during peat cutting in Orkney

Burning

• All agree: no need for burning on true blanket bog – questions over dry heath vegetation on deep peat

• "Weight of evidence” against burning on deep peat• Contradictory evidence exists

Next steps

• Best practice restoration guidelines being developed as part of Peatland Code pilot phase – online consultation later this year– Menu approach, avoiding being too prescriptive where

possible– Will include guidance on burning

• Need to work with the landowning community• Need to generate evidence

– e.g. experimental track under Peatland Code?– e.g. in this workshop on the effects of proscribing burning

on likely prices charged by landowners