Community Ecology
Communities in landscape mosaics and reserve design
Outline:
1. Goal of many ecologists is preservation of biodiversity against extinction
A. Four main causes of extinction (Shaffer 1981)
i. genetic
ii. demographic stochasticity
iii. environmental stochasticity
iv. deterministic causes
a. fragmentation
3. Reserve design
A. Corridors and connectivity
i. pros and cons of corridors
4. Metapopulations
Terms/people:
extinction (and its 4 causes)
connectivity
edge effects
metapopulation (Levins 1969)
source-sink (Pulliam 1988)
fragmentation
rescue effect (Brown & Kodric-Brown)
corridor
A primary goal of many ecologists is preservation of biodiversity against extinction.
Extinction arises through (Shaffer 1981):
-genetic causes -demographic stochasticity -environmental stochasticity -deterministic causes (e.g. fragmentation) (Be able to provide examples of each of the above.)
fragmentation  habitat loss and isolation
To combat negative effects from fragmentation: reserve design
-recall Diamond’s "design principles" (and Simberloff’s criticisms of them).
-corridors and connectivity (Figs. 12.1-12.2 in Mittelbach text)
benefits and costs
metapopulation biology
types: see Figs. 12.3-12.5 in Mittelbach text
special type: source-sink metapopulations (Pulliam 1988)
Next time: applied community ecology and future directions in community ecology
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