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

Essay styles Structured populations Review paper choose a topic, decide on a title after reading some more general papers, focus Island Mainland Make an outline Introduce the subject, explain your rationale, and state your central question, objective, or thesis. Stepping Stone model 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) Metapopulation Opinion paper similar to review, but include opinion based on facts, why this opinion/alternatives Subpopulation Classic metapopulation model Metapopulations Habitat patches are discrete All populations have a substantial (and equal) risk of Metapopulation A population of local populations extinction which are established by colonists, Equal dispersal among all patches survive for a while, send out migrants and eventually disappear. Dispersal fairly rare Subpopulation Ignore population dynamics within a patch Extinction (E) and Colonization (C) Classical metapopulation model E probability that an occupied patch will go Rate extinct. C probability that an unoccupied patch will be recolonized 0.5 1 Fraction of patches occupied

Classical metapopulation model Classical metapopulation model Metapopulation size is the number of occupied Colonization patches Extinction Rate Equilibrium occupied patches are a function of balance of ! metapopulation extinction and colonization size E > C metapopulation declines 0.5 1 E = C metapopulation is stable Fraction of patches occupied E < C metapopulation grows Metapopulation example Glanville Fritillary Melitaea cinxia Photograph by Alan Barnes 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). Metapopulation ideas important Classic metapopulation model for conservation Habitat patches are discrete All populations have a substantial (and equal) risk of extinction Migration between patches can help species persistence Equal dispersal among all patches Some species require multiple patches of habitat Dispersal fairly rare Multiple patches can spread the risk of stochastic extinction Empty patches are important Classic metapopulation not all that common, but some metapopulation ideas apply to many real systems

Source - sink metapopulations Source - sink metapopulations Habitat patches vary in quality Rescue effect: sink population go extinct Source has a high quality habitat without immigration from sources. The source rescues the sink. Sink has a low quality habitat Dispersal Dispersal Sink Sink Source Source λ < 1 λ < 1 λ ≥ 1 λ ≥ 1 Ecosystem management Source - sink metapopulations Source-sink relationships are defined by growth rate, NOT population size Ecosystem management is management of whole ecosystems rather than individual species Dispersal N c = 200 N c = 50 Sink Source λ < 1 λ ≥ 1 Ecosystem management Ecosystem management Manage for ecosystem health: allows for Manage for ecosystem health: allows for production of “ecosystem services” production of “ecosystem services” Include human activities commodities Focus on large spatial and long time scale clean water / flood control Management decisions include multiple stake aesthetics 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 Ecosystem management Stakeholders Manage for ecosystem health: allows for have a real or perceived interest in the resource, its use, its production of “ecosystem services” protection. Include human activities are dependent on the resource have a believe that management decisions will directly or Focus on large spatial and long time scale indirectly affect them Management decisions include multiple stake are located in or near the area holders pay for the decision are in a position of authority to review the decisions

Ecosystem management Adaptive management Manage for ecosystem health: allows for production of “ecosystem services” Include human activities Adaptive management treats management decisions as experiments. Change Focus on large spatial and long time scale management if data show not getting desired Management decisions include multiple stake result. holders Use adaptive management Adaptive management Adaptive management treats management decisions as experiments. Change Implement plan management management if data show not getting desired ("Let's put the plan to action") result. Baseline data Plan and design Assessment and monitoring ("How can we accomplish our ("Is the plan working?") goals?") Experimental data include comparison or/and control Evaluation and decision making ("What are our goals? Do we replicate ! need a new plan?") Adaptive management What is the effect grazing on a plant community in an open field?

We need a control! We need a control! What is the effect of grazing on the plant community in open fields? Diversity ungrazed

What is the effect of grazing on the plant What is the effect of grazing on the plant community in open fields? community in open fields? What is the point of reference/control? Replication? Diversity grazed ungrazed 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 Field 1 Field 4 What is the effect of grazing on the plant community in open fields? Diversity Field 2 Field 3 grazed ungrazed

Adaptive management: Take 2 Ecosystem and resilience 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] Resilience is the magnitude of disturbance that can be Commitment to improve the outcomes of management absorbed or accommodated by an ecosystem before over biological time scales. its structure is fundamentally changed to a different state. Awareness of the experimental nature of management. Example: Shrubland turns into grassland, grassland Willingness to accept the risk of perceived failures. turns into desert. A common understanding, with stakeholders , of the goals, strategies, and uncertainties of management. A mandate for action from the stakeholders or other Holling 1973 authorities Fire regime for different ecosystem types Use of natural processes to manage ecosystems Preservation of an ecosystem was often synonym with keeping the “status quo”, this resulted very often in damaging the ecosystem. Fire Forest and Woodland Types Understory fires 0 to 10 years Understory fires 0 to 34 years Mixed severity fires 0 to 34 years Mixed severity fires 35 to 200 years Grass and Shrub Types Mixed severity fires 201 to 500 years Mixed severity fires 500+ years Mixed severity fires 0 to 34 years Stand replacement fires 0 to 34 years Stand replacement fires 0 to 10 years Stand replacement fires 35 to 200 years Stand replacement fires 0 to 34 years Stand replacement fires 35 to 100 years Other Stand replacement fires 201 to 500 years Stand replacement fires 500+ years Stand replacement fires 101 to 500 years Water Figure 1-2 —Fire regime types based on Kuchler’s Potential Natural Vegetation types (prepared by Jim Menakis). Adaptive management: Learning from errors. Burning of Long-leaved pine forests during growing (back) and non-growing season (front) Prescribed fires Fire suppressed Hardwood confined Hardwood to understory dominant

Use of natural processes to manage ecosystems Preservation of an ecosystem was often synonym with keeping the “status quo”, this resulted very often in damaging the ecosystem. Fire Water flow Use of natural processes to manage ecosystems Preservation of an ecosystem was often synonym with keeping the “status quo”, this resulted very often in damaging the ecosystem. Fire Water flow Herbivory Zonation management Exclusion area Managed area Core protection area