ESRM 362

What is Autecology?
The study of the interactions of an organism or species with the living and non-living factors of the environment
(Growth and Survival Traits)
What Traits distinguish one species from another?
i. Growth rate
ii. Lifeform
iii. Life span
iv. Biomass allocation
v. Ability to withstand environmental conditions
vi. Rooting depth
vii. Photosynthetic pathway
viii. Nitrogen fixation
ix. Mycorrhizal host
x. Phenology
Why do species occur where they do?

example: why do some things live in shade?

Response to environmental conditions:

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Drought, heat/cold, Inundation, fire, Sun/shade, Edaphic properties

Grazing, Predation, Fossorial Mammal, Disturbance, Human disturbance

What is the primary method by which plants establish in new areas?
Which reproductive traits differ among species?
Age of first flowering
Phenology (timing)
Pollination method
Seed size
Seed quantity

Seed dispersal
Seed longevity

What are seed dispersal methods?
Zoochory (internal or external)
Ballistic (self-propelled)
What is synchroneity?
Some plants flower consistently, others irregularly
Now that we have thought about individual species, what happens when we think of them together in communities?
They interact
What kind of webs are defined in trophic interactions? What are their traits
Nest webs: Each species rely on each other to nest

Food webs: Each species relies on each other to eat

What are the three main classifications of organisms in trophic webs?
Primary (herbivores/omnivores)
Secondary (omnivores/carnivores
What is a keystone species?
A species that has a disproportionate effect on the environment relative to its biomass

May structure ecosystems, determine the types and numbers of other species in a community

Examples? Predators can greatly effect prey behavior

What is a trophic cascade?
Occur when predators reduce the abundance of their prey, thereby releasing the next lower trophic level from predation
“What if the sea otters disappear?”
Greatly simplified food web…Nothing is eating the sea urchins so the urchins eat all the starfish and it continues on
What happened in Yellowstone (wolves)?
Wolves ate a lot of elk and the Aspen populations went back up.

The elk stopped browsing the riparian areas and moved into the uplands

Wolf population increased/ elk population decreased

How can predators effect landscape levels?
Wolves gone, more elks eating trees on river banks, river banks have increased erosion rates
Is wolf reintroduction passive restoration?

Other examples?

Advantages and disadvantages of this approach??????

What should be used as targets for restoration?
Many targets possible:
All native species
Mostly native species
Pre-settlement (1850) composition
Pre-European (1491) composition
Pre-Native American (??) composition
Pre-historic (13,000 BP) composition
How should we establish goals?
Based on ecological assessment

Also based on context:
Example: Carbon offsets

Must be established a priori

May or may not be historical

What are some non-historical restoration goals?
Non historical targets:
% native species
Diversity metrics: total vs. patch diversity
Abundance of Focal species: rare or keystone species
Ecological Processes: nutrient cycling, hydrologic attenuation
What are some challenges to setting goals
Incomplete information
Uncertainty about future
Industrial rates of change
Ecosystems are complex
Spatially and temporally dynamic
Initial conditions matter
What do successful restoration models require?
May need sequential references with which to assess restored states
What is a restoration model?
Developmental trajectories

Especially required for long-term goals

How can thinking about biodiversity guide restoration practice?
What are some of the causes of the necessity for dry forest restoration?
Anthropogenic alterations

High Grade Logging

Fire Suppression

What are dry forest restoration objectives?
Plan and Treat and Multiple Scales

Build resistance to wildfire

Promote resilience to insect outbreak

Conserve Old-growth structure

Sustain local communities

Create and maintain management options

What are some dry forest restoration principles and their effects?
Reduce surface fuels -> Reduces potential flame length

Increase height to live crown -> Requires longer flame length to begin torching

Decrease crown density -> makes tree-to-tree crown (fire less probable)

Keep big trees of resistant species -> Less mortality for same fire intensity

What is Clump distribution?
A major premise used in dry forest restoration
What are the most important strategic foci when deciding how to restore a dry forest area?
Clump size and distribution

Tree type choice

Decide whether or not to keep old trees

How to thin

Isolate certain species?

Preserve wildlife habitat?

Where does the cluster method work well (dry forest restoration)
Even aged stands with few old trees

high graded stands with some old trees

Plantations: PCT

Where are cluster methods not useful? (dry forest restoration)
Stands with major tree health issues

Stands of where most of desired density is comprised of old trees

What are the three elements of biodiversity?



How relevant are biodiversity elements (Structure, Composition, Function) as restoration goals?
Variables are:
Easy to measure
Static (don’t change quickly)

A common restoration criterion
Focus on mean values and, increasingly, range of variation

Might reflect particular site differences
Ignores mechanisms that maintain structure

Variables are:
Somewhat easy to measure (need ID skills)
Fairly static (don’t change quickly)

A common restoration criterion

Ignores mechanisms that maintain composition

Variables can be:
Difficult to measure (e.g., CO2 flux)
Dynamic – fluctuate spatially and temporally

Need to choose the right variable!

Requires strong understanding of ecosystem

Why is Function unique in comparison to Structure and Composition? (Biodiversity?
More generic than structure or composition
E.g., same process can occur with different suites of species
More relevant in light of climate change?

Often assumes that structure and composition will develop once processes are ‘fixed’
E.g., estuarine restoratio

What would define a structural approach (biodiversity) to removing trees in a project?
Decide on desired forest structure (e.g., using reference data)

Compare extant and desired structures to develop thinning prescription:
How many trees to cut
Which sizes of trees to cut

Model how ecosystem process (fire behavior) responds to treatment

What would define a compositional approach (biodiversity) to removing trees in a project?
Favor some species over others
E.g., Retain fire-tolerant species, remove fire-sensitive species

Not a primary focus in SW:
Forest contains few tree species
Tree species present haven’t changed greatly

Invasive species

What would define a functional approach (biodiversity) to removing trees in a project?
Decide on desired fire behavior

Model fire behavior under various stand management alternatives:
How many trees to cut
Which sizes of trees to cut

Choose simplest alternative that achieves desired fire behavior

Measure resulting forest structure

What is a keystone species?
A species that if removed will greatly alter the environment.

It has a disproportionate effect on the environment relative to its biomass

What is a keystone process?
A process necessary to the balance of an environment. Removal or alteration will guarantee a shift in the environment.
How does fire work as a keystone process?
Forests were maintained in an open state by fire

Fire is missing now, so let’s put it back

What are reference dynamics?
Example: fire frequency
Are approaches to biodiversity exclusive?
No they are interchanging and usable in coexistence
What are the scales of biodiversity?
Population / species
Community / ecosystem
How do the scales of biodiversity matter in restoration?
How much genetic variation do you want in planting stock?
Horticulture: little
Restoration: lots

Clonal plants: very little genetic variation

Adaptation to site

For a given species:
Where to plant it?
Evenly distributed?
How many to plant?
When to plant it?
All same age, or in cohorts?

Which species to plant together?
Relation between species and environmental conditions
E.g., wet habitats
Interactions – pollinators, etc.

Scale that receives most attention during restoration


Relation of restored areas to matrix
Energy and nutrient flows
Distribution of patches

How / why do disturbances matter for restoration?
What is a disturbance?
A relatively discrete event in time that disrupts ecosystem, community, or population structure and changes the resource, substrate availability, or physical environment
Examples of disturbances?
Why do disturbances differ?
Ecological legacies
Historical contingency
Resource availability
Patch size
Pattern and process
What is an ecological legacy? (Disturbances)
the living organisms, dead organic matter, and the physical structures … that remain after disturbance
What is historical contingency (Disturbances)?
Is a disturbance within the range of variation of historical disturbances?
Define resource availability (Disturbances)
More productive sites have more resources
We can alter productivity
What is frequency (disturbances)?
Depending on the ecosystem, increases or decreases in frequency can cause problems
How does patch size play into disturbances?
Large patch
Regeneration succession

Small patch(es)
Patch dynamics
Little change in composition

Heterogeneity of disturbance effects increases species diversity

What is specificity (disturbances)?
Who is affected?
What are the three themes of disturbances and which disturbances fall into each category?
Initial conditions:

Ecological legacies
Historical contingency


Resource availability

Ongoing dynamics:

Patch size
Pattern and process

How do disturbances apply to restoration?
Restoration often (always?) involves intentional disturbances

Appropriate’ disturbances depend on:
restoration goals

How can disturbance ecology inform restoration projects?

Are site physical conditions appropriate relative to restoration goals?
Are invasive species present?
Do desired species need to be planted?
How similar is disturbance to historic ones in this ecosystem?


Are resource levels appropriate?
More productive sites often have more plant growth – especially by ‘weedy’ species – and faster growth rates
Some species are disturbance-dependent


Disturbance characteristics affect community composition and structure
How often is disturbance required?
Do disturbances target particular species?
Eg, selective herbicide use
Eg, fires to kill fire-sensitive species

What are the three categories of disturbance resistance?
Stable: able to return to starting value

Resistant: changed little by disturbance

Resilient: easily altered but rapidly returns to starting value

Brainstorm examples of ecosystems that are stable in spite of disturbances


Background’ levels of bark beetles
Drought in prairies
Fire in fire-adapted systems
Tides in intertidal zones
What type of disturbance is most likely to cause unstable ecosystem states?
Those not found in historical contingency

Is a disturbance within the range of variation of historical disturbances?

What is classical succession (ecosystem dynamics)?
Steady, directional change to a single equilibrium endpoint
Goal = climax community

Based largely on species traits
Competitive ability
Seed dispersal

Deterministic – easy to model
High predictability

Implies that we just need to reverse the degradation
Appropriate for minimally degraded sites
Inappropriate for highly disturbed sites?

What are the three different views of ecosystem dynamics?
Classical succession
State and transition
Persistent non-equilibrium
Define state and transition (ecosystem dynamics)
Some ecosystems change rapidly:
Crash of fishery stocks
Woody plant invasion of grasslands

Little change until a threshold is crossed

Possible to have multiple equilibriums

What are the implications for restoration of state and transition ecosystem dynamics?


‘Fits’ some systems well (e.g., rangelands)

Implies more complex management than required by classical succession
Moderate predictability

Need to understand thresholds

Initial conditions important

Management may require different actions than caused original transition

How would you restore shrubland to grassland?


What is Persistent non-equilibrium (ecosystem dynamics)?
Assumes external factors are more important than in other views:
Stochasticity (random events)
Past history (legacies)

Conceptual idea; difficult to ‘prove’
Difficult to distinguish from multiple equilibrium states

Low predictability

Relevant for urban settings?

What is meant by Manipulating Dynamics (ecosystem dynamics)?
Can achieve similar results by different activities at different spatial and temporal scales

Example: recovery of riparian vegetation in Yellowstone
Option 1: plant lots of trees and shrubs, protect from browse
Option 2: reintroduce wolves; elk stay out of riparian areas and vegetation recovers

Disturbances initiate or direct subsequent ecosystem dynamics

Models of ecosystem dynamics:
Summarize our ‘view of the world’
Can guide restoration actions
Take time and effort to evaluate

Contrast Stresses and Disturbances
Eg: Desert organisms are adapted to seasonal and yearly fluctuations in precipitation. Drought is not uncommon.

Eg. Fire, grazing, or extreme drought can affect soil quality and vegetation for many years

What are some values of arid desert landscapes?
Plant and animal species not found anywhere else
Endangered species
Indigenous food crops
Plant-derived drugs and other chemicals from drylands
Flood control, water purification, dust control, sustainable livestock use
What are threats to desert ecosystems?
Military activity
Changes to fire regime
Invasive species
Climate change
What are some abiotic limitations to desert restoration?
Loss of topsoil
late-successional species fail when planted into early successional soils.

Moisture limitations
Pulses of establishment with rain events

Landscape scale factors
Eg. Restore low land with good
soils, but if the slope above fails…

What are some biotic limitations to desert restoration?
Inoculation not possible for most species of microorganisms
Arid systems tend to be open; disturbance adds new open spaces
Herbivory, trampling
There are always more rare species than abundant species.
Tradeoff between species that establish and stabilize the soil, but their longevity and competitive ability reduce return of native species.
What is the stress-gradient hypothesis? (desert restoration)
As abiotic conditions become more stressful, facilitation interactions become more common
Facilitation is where one species’ structure or function benefits another species

Eg. In areas of lower precipitation, seedlings rely more heavily on nurse plants.

What are the two main aspects of community assembly?
Filters and Priority effects
What are the filters of community assembly?
Species differ in dispersal ability

Species differ in environmental tolerances

Species differ in reaction to disturbances:

What are the implications of the filters of community assembly?
Species selection is one of the most important decisions made during a restoration
Only a subset of species can ‘pass through’ the filters at a given site

Restoration often:
Overcomes dispersal limitation
Alters environmental conditions
Imposes select disturbances

What are Priority effects in community assembly?
Dominance generally by species that:
Are already present at site:
Extant vegetation
Seed bank
Arrive first
Describe the colonization/competition trade off
Competition/colonization trade-off
Good colonists = weaker competitors
Permits coexistence and species replacements
How can restoration control priority?
Site preparation to remove undesired species before planting

Adding species that would not colonize naturally or quickly

Do not need to assemble entire community at once
Coordinate species introductions with stages in ecosystem development
E.g., UBNA – shade
Expect some species to ‘phase out’ over time

What are the two main principles of restoration economics?
Economics deals with:
Costs and benefits
Responsible party vs No responsible party (who should pay for restoration)?
Feasible for some point sources
Those who caused damage
Eg, fines for Deepwater Horizon spill
Those who will cause damage
Eg, Mitigation banking

How are funds raised?
Specific products or activities
Volunteers – money and time
Private property owners

Name some economic valuation methods
Replacement cost: Cost of restoring a damaged system

Replacement cost multiplier: Cost of restoring an ecosystem plus additional funding for lost values during damage and uncertainty

Valuing ecosystem goods and services: Evaluate economic benefits of restoring a given good or service using a tradeable substitute. E.G, watershed for restoration vs. a water treatment plant to improve water quality

Travel cost method

Hedonic price method

What are the three dimensions of commitment?
Affective: emotional attachment to, identification with, & involvement in volunteering

Normative: perceived obligation to volunteer

Continuance (Calculative): perceived cost associated with quitting volunteering

Why do people commit?
People continue to volunteer over long periods of time because they are committed to the cause!
Volunteer retention efforts can benefit from understanding what motivates commitment
Content of recruitment messages,
Articulation of mission statements,
Provision & organization of volunteering opportunities & settings
What are the 6 dimensions of motivations to volunteer?
Socially interact
Learning & Career
Escape & Exercise
Help community
Ego Protection & Enhancement
Summarize commitment motivations and findings
Ego is an important predictor of initial participation—recruitment

Social interactions are important for particular organizations

Community is a strong predictor of commitment—enduring involvement—retention

Social factors are more significant predictors of participation & commitment to eco-restoration volunteerism
Ecological motivations appear to moderate the effects of social interactions & community, but rarely so?