unit 16a resource consumption pollution and greenhouse effect
TRANSCRIPT
16.1 Human Population Growth And Natural Resources
KEY CONCEPT As the human population grows, the demand for Earth’s resources increases.
16.1 Human Population Growth And Natural Resources
Earth’s human population continues to grow.
• Earth’s human carrying capacity is unknown. Why?
16.1 Human Population Growth And Natural Resources
• Technology has helped to increase Earth’s carrying capacity. Like what?– gas-powered farm equipment– medical advancements
16.1 Human Population Growth And Natural Resources
The growing human population exerts pressure on Earth’s natural resources. How?
• Nonrenewable resources are used faster than they form.– Coal– Oil– Natural gas
– Uranium (for nuclear power)– Minerals (especially rare heavy metals for technology)
16.1 Human Population Growth And Natural Resources
• Renewable resources cannot be used up or can replenish themselves over time. Name three examples.
– wind– water– sunlight
• Growing use of nonrenewable resources may lead to a crisis. How?
• Resources must be properly managed.
16.1 Human Population Growth And Natural Resources
Effective management of Earth’s resources will help meet the needs of the future.
• Earth’s resources must be used responsibly. Why?• Careless use of resources makes them unavailable to
future generations.• Easter Island is
an example ofirresponsibleresource use.
• Removal of trees
16.1 Human Population Growth And Natural Resources
• An ecological footprint is the amount of land needed to support a person.
• What must the land be able to produce and maintain?– food and water– shelter– energy– waste
How can you lessen your environmental footprint?
• http://www.carbonfootprint.com/calculator.aspx • Use the calculator to determine your footprint
and check the CO2 Reduction list for some easy ways to reduce your impact.
16.1 Human Population Growth And Natural Resources
• Several factors affect the size of the ecological footprint.– amount and efficiency of resource use – amount and toxicity of waste produced
16.2 Air Quality
KEY CONCEPT Fossil fuel emissions affect the biosphere.
16.2 Air Quality
Pollutants accumulate in the air.
• Pollution is any undesirable factor added to the air, water, or soil. Give two examples.
• Smog is one type of air pollution.– sunlight interacts with
pollutants in the air– pollutants produced by fossil
fuel emissions– made of particulates and
ground-level ozone
16.2 Air Quality
• Smog can be harmful to human health. How?• Acid rain is caused by fossil fuel emissions.
– produced when pollutants in the water cycle cause rain pH to drop
– can lower the pH of a lake or stream. What would this affect?
– can harm trees. How?
16.2 Air Quality
Air pollution is changing Earth’s biosphere. What is the biosphere?
• The levels of atmospheric carbon dioxide rise and fall over time.
• High levels of carbon dioxide are typical of Earth’s warmer periods. Why?
16.2 Air Quality
• The greenhouse effect slows the release of energy from Earth’s atmosphere.– sunlight penetrates Earth’s atmosphere– energy is absorbed and reradiated as heat (infrared)– greenhouse gases trap the infrared (heat) radiation
acting like a blanket.– Do we want to get
rid of the greenhouse
effect? Why or why
not?
methane (CH4) water (H2O)
carbon dioxide(CO2)
16.2 Air Quality
• Global warming refers to the trend of increasing global temperatures. Does this mean Wisconsin will be warmer in the future?
North Pole
16.3 Water Quality
KEY CONCEPT Pollution of Earth’s freshwater supply threatens habitat and health.
16.3 Water Quality
Water pollution affects ecosystems. How?
• Pollution can put entire freshwater ecosystems at risk.
16.3 Water Quality
• Indicator species provide a sign of an ecosystem’s health. What is an indicator species?
– amphibians– top predators
16.3 Water Quality
Biomagnification causes accumulation of toxins in the food chain. What does it mean to magnify something? Examine this picture – how do you think biomagnification works?
• Pollutants can move up the food chain.– predators eat contaminated
prey– pollution accumulates at
each stage of the food chain
• Top consumers, including humans, are most affected.
16.3 Water Quality
Why has Earth's human carrying capacity increased greatly? • A. Other organisms have been displaced by agriculture, so there is
more space for humans. • B. Humans have modified their environment due to technological
advances. • C. Humans can live closer together than other animals. • D. Humans are now eating fewer plants than they used to.
16.3 Water Quality
Why has Earth's human carrying capacity increased greatly? • A. Other organisms have been displaced by agriculture, so there is
more space for humans. • B. Humans have modified their environment due to technological
advances. • C. Humans can live closer together than other animals. • D. Humans are now eating fewer plants than they used to. • Correct Answer = B
Which of the following is not a renewable resource? • A. coal • B. wind energy • C. solar energy • D. drinking water
16.3 Water Quality
Why has Earth's human carrying capacity increased greatly? • A. Other organisms have been displaced by agriculture, so there is
more space for humans. • B. Humans have modified their environment due to technological
advances. • C. Humans can live closer together than other animals. • D. Humans are now eating fewer plants than they used to. • Correct Answer = B
Which of the following is not a renewable resource? • A. coal • B. wind energy • C. solar energy • D. drinking water • Correct Answer = A
16.3 Water Quality
What factor does not determine the size of an individual's ecological footprint?
• A. amount and efficiency of resource use • B. amount of waste produced • C. size of population • D. toxicity of waste produced
16.3 Water Quality
What factor does not determine the size of an individual's ecological footprint?
• A. amount and efficiency of resource use • B. amount of waste produced • C. size of population • D. toxicity of waste produced • Correct Answer = C
16.3 Water Quality
Review
• Earth’s carrying capacity for humans is unknown• Human population growth exerts pressure on resources• Changing to renewable resources can both lesson the pressure on
non-renewable resources and reduce pollution• An individual’s carbon footprint expresses the amount of carbon that
will be put into the atmosphere for that person over a given timeframe.
• Individuals can lessen their impact on the environment through small changes.
• The greenhouse effect is what keeps the Earth’s temperature moderate
• Excess greenhouse gases can increase the temperature on Earth to unhealthy levels
• Biomagnification is the increase in concentration of a pollutant further up a food chain.