KEY CONCEPT As the human population grows, the demand for Earth’s resources increases.
Earth’s human population continues to grow. Earth’s human carrying capacity is unknown. Why?
Technology has helped to increase Earth’s carrying capacity. Like what? gas-powered farm equipment medical advancements
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)
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.
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 of irresponsible resource use. Removal of trees
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.
Several factors affect the size of the ecological footprint. amount and efficiency of resource use amount and toxicity of waste produced
KEY CONCEPT Fossil fuel emissions affect the biosphere.
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
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?
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?
sunlight penetrates Earth’s atmosphere 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)
Global warming refers to the trend of increasing global temperatures Global warming refers to the trend of increasing global temperatures. Does this mean Wisconsin will be warmer in the future? North Pole
KEY CONCEPT Pollution of Earth’s freshwater supply threatens habitat and health.
Water pollution affects ecosystems. How? Pollution can put entire freshwater ecosystems at risk.
Indicator species provide a sign of an ecosystem’s health Indicator species provide a sign of an ecosystem’s health. What is an indicator species? amphibians top predators
Biomagnification causes accumulation of toxins in the food chain 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.
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.
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
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
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
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
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.