1. Humans in the Biosphere and Sustainability

2. How have humans changed the Earth?

3. What do these terms mean?
Soil erosion
Desertification
Deforestation
Overfishing
Pollution
Acid Rain

4. DESERTIFICATION Occurs in DRY climates
Once fertile soils become deserts
Caused by a combination of farming, drought, and overdrawing groundwater
*VIDEO*

5. DEFORESTATION Loss of trees/forest
What happens if there are no trees or roots? (why is vegetation important?)
SOIL EROSION, soil is exposed to heavy rain, especially in tropical areas!
*Video*

6. Overfishing Bycatch: organisms caught accidentally (as a Byproduct)
Usually discarded
Reduced biomass in trophic levels
Habitat modification/destruction
*Video!*
Save me!

7. Pollution
Examples: DDT; garbage island
*video*

8. Acid Rain Affects: Plant life & soils Aquatic environments Statues
Could cause cancer?

9. Acid RAIN in NORTH AMERICA

10. Biodiversity: the diversity of life
Several types of biodiversity
Environmental diversity (types of habitats, ecosystems)
Species diversity
Genetic diversity
Biodiversity has given us foods, medicines, and all kinds of products. Who knows what else it could provide for us?

11. What are some threats to biodiversity?
Habitat changes, fragmentation, destruction
Hunting species to endangerment or extinction
Introducing toxic substances into food webs (pollution)
Introducing foreign species into environments (invasive species)

12. Biodiversity Hot Spots

13. In the past many species went extinct due to excessive hunting
Endangered Species
In the past many species went extinct due to excessive hunting
What threats are there to species today?
Development
Deforestation
Expansion
Decreasing amounts and availability of resources
Climate Change