Essay styles Structured populations Review paper choose a topic, - - PDF document

Essay styles

Review paper choose a topic, decide on a title after reading some more general papers, focus Make an outline Introduce the subject, explain your rationale, and state your central question,

• bjective, or thesis.

Focus discussion on your objectives Document your paper thoroughly Do not use direct quotes, if you can avoid them. End with a general discussion (and the annotated literature) Opinion paper similar to review, but include opinion based on facts, why this opinion/alternatives

Structured populations

Mainland Island Stepping Stone model

Metapopulation

Subpopulation

Metapopulations

Metapopulation

Subpopulation

A population of local populations which are established by colonists, survive for a while, send out migrants and eventually disappear.

Classic metapopulation model

Habitat patches are discrete All populations have a substantial (and equal) risk of extinction Equal dispersal among all patches Dispersal fairly rare Ignore population dynamics within a patch

Extinction (E) and Colonization (C)

E

probability that an

• ccupied patch will go

extinct.

C

probability that an unoccupied patch will be recolonized

Classical metapopulation model

0.5 1

Fraction of patches occupied Rate

0.5 1

Classical metapopulation model

Fraction of patches occupied Rate Colonization Extinction Equilibrium metapopulation size

Classical metapopulation model

Metapopulation size is the number of occupied patches

• ccupied patches are a function of balance of

extinction and colonization !

E > C metapopulation declines E = C metapopulation is stable E < C metapopulation grows

Metapopulation example

Photograph by Alan Barnes

Glanville Fritillary Melitaea cinxia

Figure 1 Map of Åland in southwestern Finland showing the locations of the 42 local populations from which adult female butterflies were sampled in summer 1996 (large symbols). All known suitable meadows are shown as small circles, with meadows in which Glanville fritillary larvae were present in autumn 1995 indicated by black circles (and large symbols), and unoccupied meadows by white circles. Of the 42 local populations sampled, the 35 that survived to autumn 1996 (green circles) are distinguished from the seven that went extinct (red triangles).

Classic metapopulation model

Habitat patches are discrete All populations have a substantial (and equal) risk of extinction Equal dispersal among all patches Dispersal fairly rare

Classic metapopulation not all that common, but some metapopulation ideas apply to many real systems

Metapopulation ideas important for conservation

Migration between patches can help species persistence Some species require multiple patches of habitat Multiple patches can spread the risk of stochastic extinction Empty patches are important

Source - sink metapopulations

Habitat patches vary in quality Source has a high quality habitat Sink has a low quality habitat Sink Source

Dispersal

λ < 1 λ ≥ 1

Source - sink metapopulations

Rescue effect: sink population go extinct without immigration from sources. The source rescues the sink.

Sink Source

Dispersal

λ < 1 λ ≥ 1

Source - sink metapopulations

Source-sink relationships are defined by growth rate, NOT population size

Sink Source

Dispersal

λ < 1 λ ≥ 1 Nc = 200 Nc = 50

Ecosystem management

Ecosystem management is management of whole ecosystems rather than individual species

Ecosystem management

Manage for ecosystem health: allows for production of “ecosystem services” Include human activities Focus on large spatial and long time scale Management decisions include multiple stake holders

Ecosystem management

Manage for ecosystem health: allows for production of “ecosystem services” commodities clean water / flood control aesthetics ....

Ecosystem management

Manage for ecosystem health: allows for production of “ecosystem services” Include human activities Focus on large spatial and long time scale Management decisions include multiple stake holders

Ecosystem management

Manage for ecosystem health: allows for production of “ecosystem services” Include human activities Focus on large spatial and long time scale Management decisions include multiple stake holders

Ecosystem management

Manage for ecosystem health: allows for production of “ecosystem services” Include human activities Focus on large spatial and long time scale Management decisions include multiple stake holders

Stakeholders

have a real or perceived interest in the resource, its use, its protection. are dependent on the resource have a believe that management decisions will directly or indirectly affect them are located in or near the area pay for the decision are in a position of authority to review the decisions

Ecosystem management

Manage for ecosystem health: allows for production of “ecosystem services” Include human activities Focus on large spatial and long time scale Management decisions include multiple stake holders Use adaptive management

Adaptive management

Adaptive management treats management decisions as experiments. Change management if data show not getting desired result.

Implement plan management ("Let's put the plan to action") Assessment and monitoring ("Is the plan working?") Evaluation and decision making ("What are our goals? Do we need a new plan?") Plan and design ("How can we accomplish our goals?")

Adaptive management

Adaptive management treats management decisions as experiments. Change management if data show not getting desired result.

Baseline data Experimental data include comparison or/and control replicate !

Adaptive management

What is the effect grazing on a plant community in an open field?

We need a control! We need a control!

Diversity ungrazed

What is the effect of grazing on the plant community in open fields?

Diversity ungrazed grazed

What is the effect of grazing on the plant community in open fields? What is the point of reference/control? Replication? What is the effect of grazing on the plant community in open fields? What is the point of reference/control? Replication. YES for THIS field, but not for treatment (all fields in general) !"Pseudoreplication What is the effect of grazing on the plant community in open fields?

Field 1 Field 2 Field 3 Field 4

Diversity ungrazed grazed What is the effect of grazing on the plant community in

• pen fields?

Ecosystem and resilience

Resilience is the magnitude of disturbance that can be absorbed or accommodated by an ecosystem before its structure is fundamentally changed to a different state. Example: Shrubland turns into grassland, grassland turns into desert.

Holling 1973

Adaptive management: Take 2

Adaptive management is a process that combines democratic principles, scientific analysis, education, and institutional learning to manage resources sustainably in an environment of uncertainty. [Lee 1993] Commitment to improve the outcomes of management

• ver biological time scales.

Awareness of the experimental nature of management. Willingness to accept the risk of perceived failures. A common understanding, with stakeholders, of the goals, strategies, and uncertainties of management. A mandate for action from the stakeholders or other authorities

Use of natural processes to manage ecosystems

Fire

Preservation of an ecosystem was often synonym with keeping the “status quo”, this resulted very often in damaging the ecosystem.

Figure 1-2—Fire regime types based on Kuchler’s Potential Natural Vegetation types (prepared by Jim Menakis).

Understory fires 0 to 10 years Understory fires 0 to 34 years Mixed severity fires 35 to 200 years Mixed severity fires 201 to 500 years Mixed severity fires 500+ years Stand replacement fires 0 to 34 years Stand replacement fires 500+ years

Forest and Woodland Types

Stand replacement fires 0 to 10 years Stand replacement fires 0 to 34 years Stand replacement fires 101 to 500 years

Grass and Shrub Types

Water Stand replacement fires 201 to 500 years Stand replacement fires 35 to 200 years Mixed severity fires 0 to 34 years Stand replacement fires 35 to 100 years

Other

Mixed severity fires 0 to 34 years

Fire regime for different ecosystem types

Hardwood confined to understory Hardwood dominant Prescribed fires Fire suppressed

Adaptive management: Learning from errors. Burning of Long-leaved pine forests during growing (back) and non-growing season (front)

Use of natural processes to manage ecosystems

Fire Water flow

Preservation of an ecosystem was often synonym with keeping the “status quo”, this resulted very often in damaging the ecosystem.

Use of natural processes to manage ecosystems

Fire Water flow Herbivory

Preservation of an ecosystem was often synonym with keeping the “status quo”, this resulted very often in damaging the ecosystem.

Zonation management

Core protection area Managed area Exclusion area

Y E L L O W S T O N E P L A T E A U

Yellowstone Lake Y e l l

• w

s t

• n

e G a l l a t i n G r e e n M a d i s

• n

S n a k e

WIND RIVER INDIAN RESERVATION BEAVERHEAD- DEERLODGE NF CUSTER NF SHOSHONE NF SHOSHONE BRIDGER- TETON NF TARGHEE NF TARGHEE NF GALLATIN NF RED ROCK LAKES NWR GRAYS LAKE NWR NATIONAL ELK REFUGE YELLOWSTONE NP JOHN D. ROCKEFELLER, JR. MEMORIAL PARKWAY GRAND TETON NP

TETON GROS VENTRE BRIDGER NORTH ABSAROKA ABSAROKA-BEARTOOTH WASHAKIE FITZ- PATRICK JEDEDIAH SMITH WINEGAR HOLE LEE METCALF LEE METCALF RED ROCK LAKES

M O N T A N A I D A H O

U.S. Forest Service U.S. Fish and Wildlife Service National Park Service National Wilderness Preservation System Lands administered by the U.S. Bureau of Land Management and by states are not shown.

TETON North 10 30 Kilometers 30 Miles 10

Ecosystem modelling

Spatially explicit (GIS) Incorporate as many details as possible (Geology, Climate, ...) Incorporate human interactions/use/development Incorporate species compositions (diversity: species, genetics) (Complex and often not enough data)

Ecosystem management

Manage for ecosystem health: allows for production of “ecosystem services” Include human activities Focus on large spatial and long time scale Management decisions include multiple stake holders Use adaptive management