Transcript Restoration of Ecosystems

Restoration of Ecosystems
Jen Morse
Heather Bechtold
15 Jan 2013
West Hylebos Creek, WA
Hemlock forest in VT
Outline
• Introduction to restoration
• Myths of restoration ecology
• Lessons learned from past efforts
[Break]
• Assessing restoration and ecosystem services
• Discussion of Dodds et al. 2008
• Intervention ecology
• Discussion of Hobbs et al. 2011
Ecological restoration is the process of assisting the
recovery of an ecosystem that has been degraded,
damaged, or destroyed. It is an intentional activity that
initiates or accelerates an ecological pathway—or
trajectory through time—towards a reference state.
• Intentional activity: method, tools, implementation
• Recovery: ecosystem will be healthier than current
degraded state
• Damaged by human or natural causes
• Toward a historic trajectory or reference state
http://www.ser.org/content/ecological_restoration_primer.asp
Motivations for
restoration
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Ecosystem services
Mitigating impacts
Habitat
Aesthetic and moral concerns
Legal requirements
Improve human livelihoods
Improve ecosystem productivity
Adapted from SER and IUCN (2004). Ecological Restoration: a
means of conserving biodiversity and sustaining livelihoods
Restoration of…
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Rivers and streams
Drylands and deserts
Old agricultural fields
Prairies and savannas
Wetlands
Forests
Long leaf pine restoration, Nature
Conservancy, Sand Hills, North Carolina
Urban stream restoration,
Durham, North Carolina
Island Press: Science and Practice of Ecological Restoration Series
Part II: Restoration of Damaged Ecosystems
Spectrum of restoration
• Spanning a very wide range of size and scope
Stream reach scale: ~100m – 1km
Iraq: marshland loss of 17,000 km2
Restoration: deciding to act
1. Determine that an ecosystem is
damaged
2. Who is responsible for overseeing
the restoration?
3. Motivating factors?
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Laws, government agencies, NGOs
Goose Creek, Durham, NC, USA
Restoration: planning phase
• Goals for the restoration
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Habitat
Ecosystem functions
Appearance
• Project design
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Timeline, permits, contracts
Funding, budget
Planned restoration of
Everglades , south Florida, USA
Restoration: Implementation
Techniques
• Engineering interventions
• Disturbance regime
• Native species
• Invasive species
Restoration: post-implementation
1. Monitoring
2. Reporting
3. Evaluation
Myths of restoration ecology
Hilderbrand et al. 2005. The myths of restoration ecology. Ecology and Society 10:19
Myth: simplified guiding principle
- limitations and assumptions?
Carbon copy
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Goal: previous or reference state
Clementsian view: static endpoint
Disturbance is not good
Specific composition
Restoration = “accelerated
succession”
Hilderbrand et. al. 2005. The myths of restoration ecology. Ecology and Society 10:19
Field of Dreams
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“If you build it, they will come”
Physical template
Assembly process  repeatable trajectory
Wetland and stream restoration
– “self-design”
• Effectiveness is debated
Hilderbrand et. al. 2005. The myths of restoration ecology. Ecology and Society 10:19
Fast-Forwarding
• Accelerate ecosystem development
• Initial species composition determines end point
– Vegetation planting
• Recreate links between biota and physical
environment
• Motivated by need to show rapid recovery (<5y)?
• Little evidence that acceleration is successful
Cookbook
• Same techniques across all projects
• Use handbooks (engineering approach)
• Rarely adaptive, often ignore
uncertainty
• How idiosyncratic are ecosystems?
Command and Control
(Sisyphus Complex)
• Common in natural resources mgt.
• Active intervention and control
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Manage ecosystem state indefinitely
Frequent intervention decreases system resilience
Treating symptoms of the problem
Political-social mandates to “do something”
Moving Beyond the Myths
• Provide a starting point for restoration design
• Identifying themes:
– Planning for surprise, allow for uncertainty
– Helps to set realistic goals
• Incorporating science:
– Experiments in adaptive
management
– Testing multiple approaches
• Final myth: Bionic World
Myths of restoration ecology
Hilderbrand et al. 2005. The myths of restoration ecology. Ecology and Society 10:19
Myth: simplified guiding principle
- limitations and assumptions?
Restoration Efforts
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> $ 1 billion/ yr spent
Habitat Degradation
Invasion of Species
Climate Change
# of restoration projects recorded in NRRSS
Bernhardt et al 2005
Habitat Degradation
• Land-use change
– Agriculture
– Urban development
• Restoration goals
– Return an ecosystem to some previous state
– Determined by political or agency groups
– Tools needed to evaluate success of projects
How do you evaluate ecosystem health?
Observational evidence:
Sept 2008
June 2009 Craig Miller
Measure physical or biotic structure
• Increase habitat and create complexity
• Biotic indicators
– Abundance, diversity and presence/absence
– Space and time
Old-Growth
Streams:
– Fish, invertebrates
– Algae
– Riparian vegetation
Sensitive
Tolerant
Measure Functional Processes
• Can be equated with ecosystem-level
– Rates and pattern of processes
• Less commonly used in ecological assessments
• Integrate abiotic and biotic aspects
• Examples of functional processes
– Leaf decomposition
– Nutrient retention
– Metabolism
• Compare function across sites
– Within or across landscapes
– Multiple streams, forests, grasslands etc.
NCEAS: National Center for Ecological
Analysis and Synthesis
To develop a common set of metrics by
which to measure stream restoration
success.
Examine the links between ecological
theory and stream restoration
Develop a series of specific
recommendations on how stream
restoration is carried out and success is
evaluated.
Disseminate this information broadly
(http://nrrss.nbii.gov/)
Determining Restoration Success
• 93% of restoration projects are
considered successful
– Post-project appearance
– Positive public opinion
– over half had no measurable goals/
lack success criteria
Bernhardt et al. 2005, Palmer et al. 2010
Determining Restoration Success
• Pre and post monitoring efforts are
lacking from 90% of projects
– Mean project cost with monitoring
efforts are higher ($1.5 compared to
$0.4 billion)
– Low effort data collection and
analyses for assessment is needed
– Earn mitigation credits or have
incentives
Bernhardt et al. 2005, Palmer et al. 2010
Assessing ecosystem restoration
Dodds et al. 2008
Successful Restoration
• Target more than physical structure
– Enhanced habitat heterogeneity does not relate to increased diversity
– Restore functional processes
– Use of softer self sustaining techniques (i.e. floodplain instead of
armor)
• Suite of stressors
– Target most limiting factor
• Assessment and long-term monitoring
– Habitat , species
– Function
• Preservation and protection
– Incentive programs (CRP-USDA)
– Storm water management
Roni et al. 2008, Palmer et al. 2009
Restoration Ecology?
• Young discipline is maturing (into what?)
• Context of rapidly changing environment
• Jargon/terminology of ‘restoration’
– (reclamation, rehabilitation, revegetation)
creates unrealistic expectations
• To some previous or original condition
• Offsets: degradation in one area can be
replaced by an EQUAL system in another
Basic principles and tenets of
restoration ecology are (still)
being debated
• How far should turn the clock back?
– Past ecosystem state had characteristics more
desirable than today
– Historic impact is often ignored
• Rate of change has escalated and in multiple
ways
– Synergistic interactions, novel conditions and
species combinations, no analogue environments
When should humans intervene?
Intervention Ecology
Need to use an approach that focuses on how humans intervene,
maintain or repair ecosystems
• Mash up between conservation AND restoration
• Active vs. passive attempts to retain diversity or function
– Using Reactive, Active, and Proactive Interventions
• Intervene by managing for future change
• Achieve whatever goal is SET: what is your intention
– maintain a system in current desirable state or move it away from this state
• Ex: fencing vegetation, removing weed spp, AND/OR return natural
flow or fire regimes
How do you conserve a dynamic system?
Deepwater horizon oil spill in Gulf
of Mexico
• Reactive:
– stop flow of oil, limit damage to shore ecosystems, repair these
ecosystems
• Active intervention:
– re-vegetation, oil removal from impacted species, fishery enterprises,
tourism
• Proactive:
– rebuilding barrier islands or coastal habitat; reduce dependence on oil;
ecological planning for drilling areas; marine reserve program;
• How risky are these actions? What is lost if failure is the
result? (money?, species? time?)
Thanks!
Mountaintop removal coal mining, WV
Global/regional/local x ecosystem/governance
• Reactive:
• Active:
• Proactive:
Ecosystem Type
Reactive
Active
Proactive
Eastern temperate forest
Great plains
North American Deserts
Western Forested Mtns
West-coast marine forests
Wetlands
Which are feasible, desirable and likely to result in positive outcome for
humanity and biodiversity?