Diapositive 1

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SER Summer School Restoration Ecology 2009
Natural recolonisation and ecological restoration
of La Crau steppe plant communities after
cultivation abandonment
Renaud Jaunatre Advisors Elise Buisson Thierry
Dutoit
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INTRODUCTION Context
Previous studies on dry grasslands On former
cultivation Weak regeneration/dispersion -few
seeds produced -not dispersed far -not very
competitive with dense stands of ruderal species
(Hutchings Booth Zobel Verkaar Gibson Brown
Poschlod Baker, etc. In Crau Rommermann
Buisson Dutoit)
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INTRODUCTION Context
Previous studies on dry grasslands On former
cultivation Weak regeneration/dispersion -few
seeds produced -not dispersed far -not very
competitive with dense stands of ruderal
species Plant community can be improved
(species richness composition) (Pywell Kiehl
Donath, etc.) -hay transfer -sheep
grazing (Coiffait)
(Hutchings Booth Zobel Verkaar Gibson Brown
Poschlod Baker, etc. In Crau Rommermann
Buisson Dutoit)
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INTRODUCTION Context
PhD project linked to the creation of a
mitigation bank
Rehabilitation of an old orchard to a steppe
like habitat a strong partnership with
-CDC biodiversité -Ingénierie
écologique -CEEP Transfer of previous results
to an operational scale (380 ha)
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INTRODUCTION Questions
1- What are the drivers of plant community
recolonisation after cultivation
abandonment? 2-What kind of ecological
engineering techniques would be efficient to
restore the reference plant community?

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INTRODUCTION
Geographical Situation
Alpilles range
Crau steppe
Camargue wetlands
Berre Lagoon
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INTRODUCTION
Geological context
Former Durance river bed
Durance
Rhône (present)
-1 800 000 years
-800 000 years
-120 000 years
-10 000 years
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INTRODUCTION
Ecology
Stones (70) and red mediterranean soil
40cm
Conglomerate
1-5m
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INTRODUCTION
Ecology
Stones (70) and red mediterranean soil
40cm
Conglomerate
1-5m
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INTRODUCTION
Ecology
Stones (70) and red mediterranean soil
40cm
Conglomerate
1-5m
Exceptional ecological conditions
gt Exceptional ecosystem
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INTRODUCTION
The Coussoul

• Pseudosteppe
• -Plant association Asphodeletum fistulosi
• Brachypodium retusum
• Asphodelus ayardii
• Stipa capillata
• Taeniaterum caput-medusae
• Thymus vulgaris
• gt40 sp. / m²
• 50 of annuals
• unique association
• (Devaux et al., 1983)

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INTRODUCTION
History
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INTRODUCTION
History
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INTRODUCTION
History
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INTRODUCTION
History
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INTRODUCTION
History 50 000 ha gt 11 000 ha
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Questions
1- What are the drivers of plant community
recolonisation after cultivation abandonment?

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Drivers Hypothesis
Plant community recolonisation
Plant dispersion
Plant establishment
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Drivers Hypothesis
Plant community recolonisation
Plant dispersion
Plant establishment
Available species pool
Landscape characteristics
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Drivers Hypothesis
Plant community recolonisation
Plant dispersion
Plant establishment
Available species pool
Soil properties
Landscape characteristics
Cultivation and Fallow history
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Drivers Protocole
Plots choice Coussoul gt cultivation gt fallow
40 fallows -cultivation duration -abandonment
date -landscape properties 11 plots on
reference ecosystem
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Drivers Protocole
Fallows and reference ecosystem characterisation
-Vegetation relevés -Physico-chemical soil
properties -Microbial Community Structure
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Drivers Protocole
4- Correlation?
?
Vegetation Soil Microbial community
Fallow history Lanscape properties
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Drivers Perspectives
5- Representation Successionnal trajectory after
cultivation abandonment -Understand
community recolonisation -Assess ecological
engineering techniques
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Ecological Restoration
2-What kind of ecological engineering techniques
would be efficient to restore the reference plant
community?
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Ecological restoration Cossure orchard
1992 - 2006
380 ha
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Ecological restoration preliminary step
Rehabilitation of a steppe-like
habitat Orchard
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Ecological restoration preliminary step
Abandoned orchard
Rehabilitation of a steppe-like habitat
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Ecological restoration preliminary step
Trees are cut down
Rehabilitation of a steppe-like habitat
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Ecological restoration preliminary step
Trees are exported
Rehabilitation of a steppe-like habitat
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Ecological restoration preliminary step
Trees are exported
Rehabilitation of a steppe-like habitat
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Ecological restoration preliminary step
Soils are levelled
Rehabilitation of a steppe-like habitat
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Ecological restoration Objectives
Short-term -Minimize unwanted taxa -Maximize
caracteristic taxa Mid-term -Lead plant
community towards reference ecoystem
trajectory Long-term -Restore richness,
structure and composition of the coussoul plant
community
2-4 years
3-10 years
50-200 years
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Ecological restoration tested techniques
Nurse species seeding
Seeding
-Temporary herbaceous cover (Festuca Lolium -
Onobrychis)? -Nutrient use
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Ecological restoration tested techniques
Structuring species transfer
Brachypodium retusum in nursery
-Permanent cover of a local species -Structuration
of plant community
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Ecological restoration tested techniques
Hay transfer
Hay transfer
Ungrazed area
- Supply of local species pool
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Ecological restoration tested techniques
Hay transfer Sawdust
Hay transfer
Ungrazed area
-Supply of local species pool Nitrogen
mobilization flash effect by microorganisms
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Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
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Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
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Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
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Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
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Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
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Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
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Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
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Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
46
Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
47
Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
48
Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
49
Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
50
Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
51
Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
52
Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
53
Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
54
Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
55
Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
56
Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
57
Ecological restoration tested techniques
Soil inoculation
-Supply of local species pool (annuals
clonal perennials) - Supply of Symbiota
association
Area destined to be destructed
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Ecological restoration tested techniques
Sheep grazing
Ewe on coussoul
-Unwanted species elimination and regulation of
the competition/facilitation balance?
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Ecological restoration protocole
-Vegetation relevés -Physico-chemical soil
properties -Microbial Community Structure
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Ecological restoration perspectives
-Assessment of ecological restoration techniques
with regards to the model previously worked out
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La restauration conclusion
-Assessment of ecological restoration techniques
with regards to the model previously worked out
?
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Thanks