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Restoration EcologyRestoration EcologygygyIntroduction

Rudy van DiggelenRudy van Diggelen

(With i l th k t Ji H i )(With i l th k t Ji H i )(With special thanks to Jim Harris)(With special thanks to Jim Harris)

I hI hIs there a Is there a problem?problem?problem?problem?

BiodiversityBiodiversity

epl,

1987

Suk

opp

& T

reS

Ecosystem services for Ecosystem services for iisociety:society:

t t ti i fl d l it t ti i fl d l iwater retention in floodplainswater retention in floodplains

Airborne sulphur pollutionAirborne sulphur pollution

ChallengesChallengesgg

• Global climate change• Sea level rise• Agricultural intensification• Food, water and energy security

L f bi di it• Loss of biodiversity

Ecological RestorationEcological Restoration

Ecological restoration is the process of g passisting the recovery of an

t th t h b d d decosystem that has been degraded, damaged or destroyed (SER 2002)damaged, or destroyed. (SER 2002)

Restoration ecolog sRestoration ecolog sRestoration ecology vs. Restoration ecology vs. Ecological restorationEcological restorationEcological restorationEcological restoration

E l i l t ti i i t lEcological restoration is a societal activityactivity

Restoration ecology is a scientificRestoration ecology is a scientific discipline

Restoration EcologyRestoration Ecology

Restoration Ecology is the scienceRestoration Ecology is the science behind Ecological Restoration

Goal of Restoration EcologyGoal of Restoration Ecology

Prediction of the restoration trajectory and endpoint(s)trajectory and endpoint(s)

Target

ute

TargetRange

attr

ibu

Restoration

yste

m Restoration

Succession

Ecos

y

AdverseAdverse

Time

Goal of Ecological Restoration Goal of Ecological Restoration

Enhance sustainable use of the earth’s resourcesearth s resources

What What ––and howand how-- to restore?to restore?

• ValuationValuation• Level of ambitionLevel of ambition• TargetsTargets

E l i l l ti E tE l i l l ti E tEcological valuation: Ecosystem Ecological valuation: Ecosystem healthhealthhealthhealth

• Vigour – activity, metabolism, or primary g y, , p yproductivity,

• Organisation diversity and number of• Organisation – diversity and number of interactions between system components

• Resilience (or counteractive capacity) – a system’s capacity to maintain structure and y p yfunction in the face of stress.

ValuationValuation

• Vigour – activity, metabolism, or primary productivity;p y;

• Organisation – diversity and number of interactions between system components;interactions between system components;

• Resilience – a system’s capacity to y p ymaintain structure and function in the face of stressof stress

E l i l l ti E tE l i l l ti E tEcological valuation: Ecosystem Ecological valuation: Ecosystem ServicesServicesServicesServices

• Regulation functions: providing maintenance ofRegulation functions: providing maintenance of essential ecological processes and life support systems;systems;

• Habitat functions: providing suitable living space for “wild” plant and animal species;for wild plant and animal species;

• Production functions: providing natural f hi h t k dresources from which to make goods

(consumable and structural); and,• Information functions: providing opportunities for

cognitive development.g p

What are theWhat are theWhat are the What are the obstacles?obstacles?

BioticAbiotic

Fully- RequiresPhysical

RequiresBiological

functional1

PhysicalModification Modification

233

4RequiresImproved

56

Improved Management

6ReclamationReclamation RestorationRestoration

Degraded Intact

Non-functional

Degraded IntactECOSYSTEM STATE

EASY!!EASY!!Biotic barrierAbiotic barrier

R i R i R iFully-functional

RequiresPhysico-chemicalModification

RequiresBiologicalModification

RequiresImproved Management

12

EcosystemAttribute

34

556

Degraded Intact

Non-functional

ECOSYSTEM STATEECOSYSTEM STATE

Difficult!!!Difficult!!!Biotic barrierAbiotic barrier

R i R i R iFully-functional

RequiresPhysico-chemicalModification

RequiresBiologicalModification

RequiresImproved Management

12

EcosystemAttribute

34

556

Degraded Intact

Non-functional

ECOSYSTEM STATEECOSYSTEM STATE

Targets?Targets?Targets?Targets?

Concepts of NatureConcepts of Nature

• Wilderness concept (‘natural landscapes’)p ( p )• Arcadian concept (‘semi-natural

landscapes’)landscapes )• Functional concept (‘rural landscapes’)p ( p )

Swart et al. 2001

Natural targetNatural target

Cultural targetCultural target

Alternative targetsAlternative targetsAlternative targetsAlternative targets

Harms et al. 1993

ffTypes of targetTypes of target

• species;p ;• ecosystem functions; and,ecosystem functions; and, • ecosystem services.ecosystem services.

Species Species pp

K tKeystoneEndangeredgAssemblagesAssemblages

Restoring keystone speciesRestoring keystone species

Restoring species assemblagesRestoring species assemblagesRestoring species assemblagesRestoring species assemblages

Restoring ecosystem functions:Restoring ecosystem functions:g yg y

material and energy flowmaterial and energy flowmaterial and energy flowmaterial and energy flow

Restoring ecosystem functions:Restoring ecosystem functions:

ecosystem architectureecosystem architecture

Restoring ecosystem services:Restoring ecosystem services:Restoring ecosystem services:Restoring ecosystem services:

regulation (nutrient removal)regulation (nutrient removal)regulation (nutrient removal)regulation (nutrient removal)

Restoring ecosystem services:Restoring ecosystem services:

informationinformation

H tH tHow to measure How to measure the degree ofthe degree ofthe degree of the degree of

success?success?success?success?

Successfull restoration?Successfull restoration?

Reference EcosystemsReference Ecosystems

• Site audits prior to damage• Site audits prior to damage• Historic and recent photographyp g p y• Site remnants• Ecological descriptions of similar sites

Herbarium and museum specimens• Herbarium and museum specimens• Historical accounts and oral historiesHistorical accounts and oral histories• Palaeoecological evidence

Historical referencesHistorical referencesHistorical referencesHistorical references

Palaeoecological referencesPalaeoecological referencesPalaeoecological referencesPalaeoecological references

MMMacroMacro--remnantsremnants

This is what we findThis is what we findThis is what we findThis is what we find

Past vegetation mapsPast vegetation mapsPast vegetation mapsPast vegetation maps

We found thisWe found this

and this …..and this …..

l thil thialso this …..also this …..

and much more …..and much more …..

So, what do you want?So, what do you want?

A moving targetA moving targetA moving targetA moving target

DEGRADEDDEGRADED

P t b tiPerturbation

ORIGINAL

A moving targetA moving targetA moving targetA moving target

DEGRADEDDEGRADEDRestoration

P t b tiPerturbation

ORIGINAL

A moving targetA moving targetA moving targetA moving target

DEGRADEDDEGRADEDRestoration

P t b tiPerturbation

ORIGINAL CURRENTTime

A moving targetA moving target

DEGRADEDDEGRADEDRestoration Restoration?

P t b tiPerturbation

ORIGINAL CURRENTTime

Target

ute

TargetRange

attr

ibu

Restoration

yste

m Restoration

Succession

Ecos

y

AdverseAdverse

Time

e

TargetRange

trib

ute Range

em a

tt Restoration

osys

te Succession

Eco

AdverseBoth barriers in place

Time

Target

ute

TargetRange

attr

ibu

Restoration

yste

m Restoration

SuccessionFailure 2

Ecos

y

AdverseFailure 1

Adverse

Time

Attributes for restoration successAttributes for restoration successAttributes for restoration successAttributes for restoration success

Ch t i ti A bl f i• Characteristic Assemblage of species• Indigenous species (exotics when extinct)• All functional trophic groups• Appropriate physical environment• Normal functioning of cycles• Integrated into a larger landscape• External threats eliminated or reduced• Resilience to perturbationp• Self-sustaining

SER 2002SER 2002

Level of ambitionLevel of ambition

• Reclamation - increase biodiversity per seReclamation increase biodiversity per se• Rehabilitation - restoration of certain

t f tiecosystem functions• Restoration (s.s.) – reconstruction of a ( )

previous situation

Success criteria in relation to ambition levelSuccess criteria in relation to ambition level

Ambition level

Attribute Reclamation Rehabilitation Restoration

Characteristic Assemblage of species - - √

I di i √Indigenous species - - √

All functional trophic groups - - √

√ √Appropriate physical environment - √ √

Normal functioning of cycles - √ √

Integrated into a larger landscape √ √ -

External threats eliminated or reduced √ √ -reduced

Resilience to perturbation √ √ -

Self sustaining √Self-sustaining √ - -

Criteria for ecological indicatorsCriteria for ecological indicators

• Easily measured• Sensitive to anthropogenic pressures• Anticipatory – early signal of a “treatable” larger problemAnticipatory early signal of a treatable larger problem• Allow for adaptive management intervention• Integrative• Integrative• Have known responses to stress, disturbances and time• Low variability in response

Derived from Dale and Beyeler 2001

Remaining QuestionsRemaining Questions

• What is an “appropriate” species?• What is an appropriate species?• How do we integrate abiotic and biotic

processes, and provide useful measures?• How do we overcome biotic and abioticHow do we overcome biotic and abiotic

barriers?H d i t ti ?• How do we sequence our interactions?

• Are there “irreversible” thresholds?• Is this a culturally acceptable project?

S i t l C t tS i t l C t tSocietal ContextSocietal Context

Major ecological restoration will not be undertaken unless human society approves the goals and objectives of restoration Inthe goals and objectives of restoration. In addition, restoration will not persist unless human society has sufficient esteem for the restored ecosystem to protect its integrity”restored ecosystem to protect its integrity

Cairns, 2000

Ecosystem values to societyEcosystem values to society

• Direct use values fish stocks

• Indirect use values i ifi ti• Indirect use values air purification

• Optional values recreationOptional values recreation

• Non-use values species survival

Ecosystem valueEcosystem value

For the entire biosphere the value (most…..For the entire biosphere, the value (most of which is outside the market) is estimated to be in the range of US$ 16–54 trillion (1012) per year with an average ofUS$ 33trillion perper year, with an average of US$ 33trillion per year. (…) Global gross national product total

S$is around US$18 trillion per year. ….Costanza et al 1997Costanza et al. 1997

COCO22 balance naturalbalance natural AlnusAlnus woodlandwoodlandCOCO22 balance natural balance natural AlnusAlnus woodlandwoodland

CO2 Fixation CO2 Fixation 5 t CO2 ha-1 a-1

GW Ø 10 cm below soil surface

COCO fi ti d d d tifi ti d d d tiCOCO22 fixation and wood productionfixation and wood production

COCO22--FixationFixation

kg hakg ha--11 yryr--11

a) Eternal COa) Eternal CO22--Sink Sink 244244 3 7003 700)) 22(Continuous peat production) (Continuous peat production) 244 244 -- 3.7003.700

b) Temporal COb) Temporal CO22--SinkSink 7 4287 428b) Temporal COb) Temporal CO22 Sink Sink (Wood production in 70 Years)(Wood production in 70 Years) 7.4287.428

c) COc) CO Emission avoidance throughEmission avoidance through COCO SubstitutionSubstitutionc) COc) CO22--Emission avoidance through Emission avoidance through Substitution of fossile Fuels Substitution of fossile Fuels

COCO22--SubstitutionSubstitutionkg hakg ha--11 aa--11

6 0006 000Use of the wood for energy purposes Use of the wood for energy purposes 6.0006.000

Restoring alder swampsRestoring alder swampsRestoring alder swampsRestoring alder swampsfrom maize fieldsfrom maize fields

Changes in nitrogen mineralisation during rewetting

1989/90

80

1001989/90

40

60

0

20

Mai August November Februar

80

1001996/97

Mai August November Februar

5-NO3

20

40

605-NH4

0

20

Mai August November Februar

HabitatHabitatHabitatHabitatcreationcreationcreationcreation

Emerging ecosystemsEmerging ecosystems

An ecosystem whose speciesAn ecosystem whose species composition and relative pabundance have not previously

d ithi i bioccurred within a given biomeHobbs et al. 2004

Comm nit assembl nderComm nit assembl nderCommunity assembly under Community assembly under changing conditionschanging conditionschanging conditionschanging conditions

Key issues:

• Abiotic constraints are likely to develop towards levels outside of what• Abiotic constraints are likely to develop towards levels outside of what was previously characteristic

• Ecosystem process rates are likely to be different, especially because th b l d it iti i diff tthe below-ground community composition is different

• Propagule availability and dispersal processes have dramatically changed during the last century

Most likely we will get larger surfaces with ‘new’Most likely we will get larger surfaces with new ecosystems. The challenge is to predict their

i itispecies composition

Let’s do it!Let’s do it!

The proper setting of 'technical' aspects of ecological restoration within

a societal setting is clearly a cruciala societal setting is clearly a crucial task for the restoration ecologist

Harris & Van Diggelen 2004Harris & Van Diggelen 2004