2. A. Rapid Human Population Growth is the root of most of our environmental problems. Industrial Revolution Medical Advancements Farming Advancements

3. B. Biodiversity 1. Number of different organisms in an ecosystem 2. Increased biodiversity  a. Increased Stability b. Genetic variation for survival during environmental changes c. Potential medicines & food crops

4. C. Water Problems 1.Thermal Pollution: *Decreases dissolved oxygen  Organisms die Factories & power plants use water to cool machinery & dump hot waste water into rivers/lakes

5. 2. Fertilizers: Supply nutrients to help plants grow. *Runoff into streams/rivers  Lots of algae die  Rapid plant/algae growth (Algal Bloom)  Lots of decomposers deplete oxygen  Fish suffocate/die

6. 3. Pesticides – b. Can be taken in by producers and then passed through a food chain used to kill pests (Ex. DDT) a.May also harm/kill harmless insects/animals *Biomagnification* chemicals increase in concentration as are passed to higher trophic levels

7. 1. Non-biodegradable Wastes – D. Land Problems cannot be broken down * Plastic, aluminum, glass, diapers

8. 2. Deforestation:  Habitat Destruction  Decreased Biodiversity  Erosion (removal of soil by wind/water)  Increased CO 2 levels  Global Warming Clear-cutting of Forests

9. 3. Exotic/Invasive Species Organisms imported into an area from another region Examples: Purple loosestrife plant, Japanese beetle, gypsy moth, Asian longhorn beetle No natural enemies  Reproduce Rapidly  Out-competes native species  Disrupts food chain/Decreases biodiversity

10. 4. Overhunting, Overfishing, and Direct Harvesting Endangered Species (may soon completely disappear) Dodo Bird Passenger Pigeon *Could lead to the extinction of that species*

11. E. Air Problems 1.CFCs (Chlorofluorocarbons) – used in aerosols, refrigerators, air conditioners  Ozone Depletion *Allows more UV radiation to reach Earth’s surface (causes skin cancer)

12. 2. Burning of fossil fuels (coal, oil, natural gas) by cars and factories a. Increased greenhouse gases causes Global Warming  changes in climate/weather patterns  polar ice melts  rise in sea level (flooding) & habitat loss

13.  Harms aquatic ecosystems  Harms plants  Damages limestone & marble buildings b. Release of Sulfur Dioxide & Nitrogen Dioxide causes Acid Rain (rain with low pH)

14. F. Ways to Fix the Problems 1. Educate the public 3. Environmental Laws:  Protect Habitats  Regulate Overhunting/Overfishing  Control/Limit Pollution 2. Tradeoffs: Costs vs. Benefits

15. 4. Conservation of Nonrenewable (fossil fuels) and some Renewable (trees) Resources  Reduce, Reuse, Recycle  Alternate (renewable) energy sources – solar, wind, water, etc. 5. Reforestation – replant trees

16. 6. Biological Pest Controls - controlling insect populations without using pesticides a. Release natural predators b. Pest-resistant plants c. Insect Traps d. Sterilize male insects