1. Threats to Biodiversity

2. Factors that Maintain Biodiversity
Complexity of the ecosystem
More complex = more resilient
The system as a whole is stable but any particular species may not be
Stage of Succession
Species diversity increases with time until climax community is reached
Therefore young communities are more vulnerable than older ones (less complex=less resilient)
Limiting Factors
If there are already many limiting factors than any change may just make things even harder!
Inertia/persistence
Vocab: The property of an ecosystem to resist change when subjected to a disruptive force
Important for planners to know which site will resist change(inertia) or recover quickly (resilience)

3. Factors that Lead to Loss of Biodiversity
Natural Hazards
Major problem is that they lead to LOSS OF HABITAT
Humans cause similar problems

4. Factors that Lead to Loss of Biodiversity
Fragmentation of Habitat
A large areas is divided into a patch work
Roads, power lines, fences, pipelines, etc.
Fragments behave more as islands
The edge ratio gets higher as the habitat gets smaller
Edges are more vulnerable

5. Factors that Lead to Loss of Biodiversity
Pollution
Caused by humans
Includes….
Local Pollution (acute)
Pesticides, oil spills
Environmental Pollution (chronic)
Emissions from factories and transportation
Run-Off
Fertilizers (eutrophication) and toxic chemicals
Climate Change
Leads to biome shifts

6. Factors that Lead to Loss of Biodiversity
Non-Native Species (Invasive species)
Historically we have done this through colonization and or attempts at pest control
It also happens by accident
Has been good
Potatoes from Americas to Europe
Rubber trees from amazon to Asia
Has been bad
Rhododendrons out compete native plants in Europe
Sudden Oak Death imported through trade
Australia…

7. Factors that Lead to Loss of Biodiversity
Spread of Disease
Swine Flu (2010)
Bird Flu (2003)
Foot and Mouth Disease (affects animals and humans)
Black Footed Ferret (canine distemper)
Sylvatic plague and prairie dogs

8. Factors that Lead to Loss of Biodiversity
Agricultural Practices
Reduces diversity on purpose!!!!!!!!
What is a “monoculture”?

9. What the heck Australia?