Human Impact on Ecosystems

1. Human Impact on Ecosystems

2. Earth’s Human Population Continues to Grow Earth’s human carrying capacity is unknown Technology has helped to increase Earth’s carrying capacity. gas-powered farm equipment medical advancements clean water public assistance

3. Overpopulation • Over 6.6 billion people • Many natural resources are nonrenewable • Fossil fuels take millions of years to form • More people means: • 1) More forests removed • 2) More resources consumed • 3) More CO2 released

5. Earth’s Natural Resources • The growing human population puts pressure on Earth’s natural resources • Nonrenewable resources are used faster than they can form or be replenished: • Coal • Oil • Natural Gas MUST BE MANAGED EFFECTIVELY!!! • Renewable resources cannot be used up or can replenish themselves over time : • Wind • Solar • Water

6. Defined: the amount of land needed to support a person. • The land must produce and maintain enough • food and water • shelter • energy • waste • Several factors effect size: • Amount/efficiency of resource used • Amount/toxicity of waste produced Ecological Footprint

7. What are some Environmental issues Caused by human activity?

8. Ozone Layer Depletion Ozone Function: Block UV radiation from sun Cause: CFCs (air pollution) thin the ozone layer More UV radiation reaches the surface Effects: Crop damage Skin cancers Eye damage Solution: Reduce/Regulate CFCs Planttrees UV UV Ozone layer Ozone layer CFCs

9. Smog and Ground-Level Ozone Causes: Burning of fossil fuels & industry Particulates rise into air and react with sunlight to make air pollution Effects: Ozone gas (O3)is poisonous Respiratory illness Solutions: Reduce use of fossil fuels Alternative energy sources Plant trees

10. The Greenhouse Effect G.H.E. is naturally good (it warms Earth) Causes: CO2 from burning of fossil fuels (coal, oil, natural gas) Effects: Excess heat trapped near the earth’s surface may change global climate patterns; ice caps melt Solutions: Reduce use of fossil fuels, planttrees, alternative energy sources

11. What’s a Greenhouse? A Greenhouse is designed to trap heat so you can grow plants year round, even in cooler environments. heat Some heat escapes the greenhouse, but enough is trapped to keep the inside warm heat heat heat

12. Some heat escapes into space CO2 heat Some heat naturally trapped by CO2 and other greenhouse gases CO2 heat The Natural Greenhouse Effect is good for life on Earth. heat heat CO2 CO2 CO2 CO2 CO2 heat CO2 CO2 CO2 Earth CO2 CO2

13. CO2, Methane, other greenhouse gases Earth

14. More heat trapped near Earth’s surface Less heat escapes into space CO2 heat CO2 heat heat heat heat CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 heat CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 Excess CO2 in atmosphere CO2 CO2 CO2 CO2 Earth CO2 CO2 CO2 CO2 CO2

15. The Greenhouse Effect is naturally GOOD! Mars: No Greenhouse Effect Earth: Balanced Greenhouse Effect Venus: The Extreme Greenhouse Effect Little heat is trapped by the thin CO2 atmosphere. High temperatures can be around 20⁰F. Heat is trapped by the thick CO2 atmosphere. Temperatures reach 750⁰F. Average global temperature is 57⁰F.

16. Defined: Precipitation with a below normal pH Cause: Fossil fuel pollution rises into the air & then falls as rain Effects: Waterways more acidic Kills plant and animal life Solutions: Reduce fossil fuel usage Add buffer (base) to waterways Acid Rain

17. Nitric acid Sulfuric acid SO2 NO NO

20. Water pollution • Defined: pollution in water supplies • Causes: • Waste • Medicines • Agricultural Runoff • fertilizers • pesticides • Problems: • Species lost • Ecosystems harmed • Solutions: • Manage waste

21. Water pollution affects ecosystems • Indicator species: Give sign of ecosystem’s health • Example: • Amphibians • Frogs are good indicator species because their skin is water permeable. • Top predators • Solution: Waste Management

22. Biomagnification • Defined: Accumulation of toxins in the food chain • Fat soluble pollutants move up food chain. • These pollutants stay in the body fat of an organism • Predators eat contaminated prey • Pollution accumulates at each levelof the food chain • Top consumers, including humans, are most affected.

23. Deforestation Defined: Clearing of forested areas Causes: Harvesting/destroying forests for high demand: Wood products Creating farmland Effects: Species lost Excess CO2 released Solutions: Recycle Improved farming techniques

25. Introduced & Invasive Species Zebra mussels Mice Kudzu vines • Defined: Foreign organisms are introduced to a new habitat • Invasive: harms native species • Cause: • Foreign species introduced to new environment • Effects: • Foreign species outcompete native species • Food webs unbalanced • Economic damage • Solutions: • Laws preventing foreign goods into new countries • Introduce predators

26. What is being done? • The Environmental Protection Agency (EPA) • Created in 1970 • Works to protect species • Clean Water Act • Clean Air Act • Endangered Species Act • This recovered the bald eagle • Those listed are called “Umbrella Species” • Entire habitats protected

27. Review • CFCs are manmade chemical responsible for the destruction of the • Which gas is a main contributor to the greenhouse effect? • Crop damage and cancers are caused by an excess amount of which type of energy? __________________ • Name the big three fossil fuels: • Which planet has excess temperatures because of a thick CO2 atmosphere? • What is smog? • How are pollutants passed through the food chain? • Where is ozone gas harmful to life? • Where is ozone gas helpful to life? • What makes a resource nonrenewable? • Food webs become unbalanced as a result of the introduction of which type of organisms? • What is an umbrella species?