Download ENHANCING ECOLOGICAL DIVERSITY WITH MANUFACTURED

ENHANCING ECOLOGICAL DIVERSITY WITH
MANUFACTURED SOILS USING RECYCLED
MATERIALS
PHILIP PUTWAIN
ECOLOGICAL RESTORATION CONSULTANTS LTD
LIVERPOOL UNIVERSITY
CREATION OF GREEN INFRASTRUCTURE
AND ECOSYSTEM SERVICES
Water infiltration (SUDS)
Habitat corridors for
wildlife
Carbon storage and
soil stabilisation
Urban and community
parks, woodlands and
sports fields
UK STRATEGIES AND GUIDANCE
• State of Soils in England and Wales
Report – EA
• The First Soil Action Plan – Defra
• Creating a Better Place – EA
(2010-2015)
• Safeguarding our soils-A strategy
for England (2009)
• Construction Code of Practice for
the Sustainable Use of Soils on
Construction Sites (2009)
SOIL GENESIS
A role for imported organic materials
Recycled materials – organic
•
•
•
•
QP/PAS 100 green or food-based compost
QP/PAS 110 anaerobic digestate
Compost-like output
Paper crumb
Recycled materials – minerals
Quarry wastes and postindustrial sites in-situ
Mineral subsoils – development
sites in-situ
Recycled crushed brick,
demolition fines, crushed
concrete blended ex-situ
ENHANCING SOIL FUNCTIONS
HABITAT CREATION
Physical,
chemical,
biological setting
for organisms
Regulate water flow
and storage, recycling
of elements
BASIC SOIL
FUNCTIONS
Provision of
mechanical support
Support biological
activity and
diversity
Filter, buffer,
degrade, immobilise,
detoxify organic /
inorganic
After Nortcliff 2002
SOIL AND ABOVE- GROUND BIODIVERSITY
MUST BE EVALUATED IN THE CONTEXT OF
SPECIFIC ECOSYSTEMS Define the target
What constitutes a healthy soil
for a heathland ecosystem is
not the same as one for a
grassland or woodland
ECOLOGICAL RESTORATION AT CRONTON
COLLIERY TIP MERSEYSIDE
to retain the semi-natural character of the location
to use PAS 100 green compost incorporated into the spoil
to ameliorate chemical and physical properties
sufficiently to establish diverse plant communities and
enhance indigenous vegetation supported by a sustainable
and biologically diverse soil system
to add sufficient green compost to allow only the
establishment of indigenous species and sown wildflowers
but not vigorous weedy competitors
CRONTON COLLIERY TIP : STARTING POINT –
SLOW COLONISATION
Southern plateau
1998 with extensive
bare spoil
Colliery tip re-profiled 1995-6
Southern plateau 2006
with colonising
common reed
(Phragmites australis)
DESIGN OF THE TRIAL
LOCATION OF
TREATMENTS
IMPACT OF COMPOST TREATMENTS
INCORPORATED IN TOP 120 CM CONTRASTED WITH
NO COMPOST BUT CULTIVATED
May 2007 –
Spreading + rotavating
Amount 200m3 per ha
August 2007 - contrast compost vs none
Estimated mineralised nitrogen released from
applied compost: 30-50 kg/ha 1st growing
season
TOWARDS A SUSTAINABLE ECOSYSTEM
After four growing seasons
August 2010 compost top
120mm acid grassland
seed mix
34 spp
MG 10 Yorkshire fog-soft rush pasture
October 2010
compost top 120mm
wetland seed mix
indigenous tree
species colonising
‘wet woodland’
25 spp
MG10 + MG13 Creeping bent-marsh foxtail
Mean concentration
of available P
May 2007 data
2 weeks after
compost was spread
Mean concentration
of available K
WOOLSTON NEW CUT CANAL
Blends of green compost (15% v/v) with
recycled materials
• Crushed brick
• Sandy subsoil
• Demolition fines
• Crushed limestone
All QP materials
300mm depth
BS3882:2007 some fail MP
and Calcareous, all fail Acid
WOOLSTON NEW CUT CANAL
Blends of green compost with recycled materials
July 2010 Blends spread
September 2011
Crushed limestone
September 2011
Demolition fines
Shannon Wiener diversity
DF 2.7
CL 3.4
Total species per sample
DF 18
CL 21
WOOLSTON NEW CUT CANAL
Individual species percentage cover
DIVERSITY OF SOIL ORGANISMS INDICATORS
Earthworms:
epigeics
endogeics
anecics
Oribatid mites
Life history
classifications
Selected biological
indicators for soil
health and
biodiversity
Enchytraeid
worms:
feed on fungi
Protozoa:
Testate amoebae
EARTHWORMS MORPHOLOGICAL – ECOLOGICAL
GROUPS
Epiges: Small body size, surface dwelling in litter
Endoges: Variable size, horizontal branching burrows
Aneciques: Large body, deep vertical burrows
Photos courtesy of Dr. Trevor Piearce
Apporecta longa
anecic
Lumbricus
rubellus epigeic
Octolasion cyaneum
endogeic
RESTORED SOILS CRONTON COLLIERY
After 4 years
Earthworm
Cronton Colliery
species group
spoil unrestored
and pop density sparse vegetation
Cronton
restored
woodland
Lancaster Uni
permanent
grassland
Epigeic biomass
15g/m2
>200g/m2
160g/m2
Epigeic pop den
32/m2
>600/m2
No data
Sewage 135 t ds ha-1Recycled paper crumb (32% Organic carbon) 1000 t ha-1
RESTORED BIDSTON LANDFILL
MERSEYSIDE
Restoration commenced
in 1995
Objective to create
community woodland – a
mosaic of woodland and
meadow grassland
50:50 mixture of paper crumb (derived from recycled newspapers)
provided by Bridgewater paper Company and mixed with in-situ
landfill cover, spread to a depth of 500mm
Eight species of earthworm introduced (Endogeic and Anecic)
followed by six years of sampling earthworms
RESTORED BIDSTON LANDFILL
MERSEYSIDE
6 years after restoration – innoculated with grassland turves
Earthworm populations and biomass
Restored 5
years
Restored 3
years
Restored < 1
year
Total nos /m2
1005
130
51
Biomass g/m2
186
58
13
Mean no of species
per sample
5.9
3.2
0.7
Total number of
species
12 €
8
2£
Data from Piearce (2003)
€ Lumbricid spp more common
£ Compost spp dominant
CONCLUSIONS
Input of quality recycled organic
materials (QP/PAS 100 composts and
digestates) blended with mineral
aggregates/substrates provide the
starting point for the development of
ecologically diverse and sustainable
soil ecosystems
Manufactured soils tailored to particular enduses are the foundation for the creation of
green infrastructure and ecosystem services
in brownfield developments and in urban/postindustrial settings where natural topsoil is not
available in - situ
COLLABORATORS AND
ACKNOWLEDGEMENTS
WE ARE MOST GRATEFUL TO WRAP
FOR FINANCIAL SUPPORT AND CONTINUING INTEREST
MANY THANKS ALSO TO Katherine Church (WRAP), Gill Haynes
(ERC Ltd), Dr Helen Rawlinson (Mint Green Environment), Peter
Gateley and Dr Trevor Piearce (Lancaster University)
THANK YOU FOR LISTENING