KEY CONCEPT As the human population grows, the demand for Earth’s resources increases.

Objectives Summarize the current state and effects of human population growth Explain the importance of effective resource management

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

The growing human population exerts pressure on Earth’s natural resources. Nonrenewable resources are used faster than they form. coal oil

Renewable resources cannot be used up or can replenish themselves over time. wind water sunlight Growing use of nonrenewable resources may lead to a crisis. Resources must be properly managed.

An ecological footprint is the amount of land needed to support a person. The land must produce and maintain enough food and water shelter energy waste

Several factors affect the size of the ecological footprint. amount and efficiency of resource use amount and toxicity of waste produced

Give 3 examples of how technology has influenced human population growth Advances in medicine have reduced infant mortality and prolonged life spans Industrial technologies have made transportation and agriculture more productive and easier, allowing for easier food production and distribution Plumbing and sewage treatment have improved sanitation, reducing incidence of water born illness

What is the difference between renewable and nonrenewable resources Are difficult to replenish in a time span meaningful to humans Can be replenished by Earths natural processes

What factors can limit the growth of the human population? Disease Drought Overexploitation of limited resources Crop pests War

16.2 Air Quality KEY CONCEPT Fossil fuel emissions affect the biosphere.

16.2 Air Quality Objective Describe the sources, types, and effects of pollution Explain how air pollution contributes to acid rain

Pollutants accumulate in the air. 16.2 Air Quality Pollutants accumulate in the air. Pollution is any undesirable factor added to the air, water, or soil. 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. 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 can harm trees

Air pollution is changing Earth’s biosphere. 16.2 Air Quality Air pollution is changing Earth’s biosphere. The levels of atmospheric carbon dioxide rise and fall over time. High levels of carbon dioxide are typical of Earth’s warmer periods.

sunlight penetrates Earth’s atmosphere 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 greenhouse gases absorb longer wavelengths Greenhouse gas molecules rerelease infrared radiation methane (CH4) water (H2O) carbon dioxide (CO2)

Global warming refers to the trend of increasing global temperatures. 16.2 Air Quality Global warming refers to the trend of increasing global temperatures. North Pole

Name and describe 2 ways in which pollution affects ecosystems 16.2 Air Quality Name and describe 2 ways in which pollution affects ecosystems Pollution can result in smog and acid rain Smog is caused by the interaction of sunlight with pollutants produced by fossil fuel emissions Acid rain results from the mixture of these emissions with water

How does the greenhouse effect keep Earth warm? 16.2 Air Quality How does the greenhouse effect keep Earth warm? Infrared energy Radiating from Earths surface is absorbed by greenhouse molecules such as water, carbon dioxide, and methane. This energy, also called heat, is then released and absorbed by other molecules of Earths surface or the atmosphere.

16.2 Air Quality Explain how a build-up of CO2 in the atmosphere could increase Earths global temperature. With more greenhouse molecules in the atmosphere, less heat would be allowed to escape, causing Earth to become warmer.

16.2 Air Quality Greenhouse gasses are found close to earths surface and high above in the atmosphere. Name 2 important functions of greenhouse gasses at Earths surface. At Earths surface water vapor condenses to form precipitation which is part of the hydrologic cycle Carbon dioxide is a necessary reactant for photosynthesis

16.2 Air Quality Ocean producers such as phytoplankton are an important part of food webs, but they require a specific temperature range to survive. How might increased water temperature affect these ocean food webs? If increased water temperatures kill the phytoplankton, the lowest trophic levels will be gone and the food webs will probably collapse

16.3 Water Quality KEY CONCEPT Pollution of Earth’s freshwater supply threatens habitat and health.

16.3 Water Quality Objectives Describe how water pollution affects ecosystems Explain how biomagnification causes accumulation of toxins in food chains

Biomagnification causes accumulation of toxins in the food chain. 16.3 Water Quality Biomagnification causes accumulation of toxins in the food chain. 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.

How do PCBs affect bird populations through biomagnification? 16.3 Water Quality How do PCBs affect bird populations through biomagnification? PCBs travel up through trophic structure of an ecosystem and accumulate in large amounts in the eggs of large birds. PCBs can negatively impact growth and development within the egg, causing Genetic mutations Deformities Death The population of birds may crash as a result

16.3 Water Quality Would a buffalo or a mountain lion be more affected by biomagnification? Why? A mountain lion would be more affected because it is higher on the food chain and would ingest more contaminants from its food supply

How does the biomagnification pyramid compare with the energy pyramid? 16.3 Water Quality How does the biomagnification pyramid compare with the energy pyramid? They are opposite Energy decreases as you move up the food chain, but pollution increases

16.4 Threats to biodiversity KEY CONCEPT The impact of a growing human population threatens biodiversity.

16.4 Threats to biodiversity Objectives Assess the consequences of loss of biodiversity Explain how loss of habitat and introduced species affect ecosystems and biodiversity

Preserving biodiversity is important to the future of the biosphere. 16.4 Threats to biodiversity Preserving biodiversity is important to the future of the biosphere. The loss of biodiversity has long-term effects. loss of medical and technological advances extinction of species loss of ecosystem stability

Loss of habitat eliminates species. 16.4 Threats to biodiversity Loss of habitat eliminates species. Habitat fragmentation prevents an organism from accessing its entire home range. occurs when a barrier forms within the habitat often caused by human development

Habitat corridors are a solution to the problem. corridors can be road overpasses or underpasses allow species to move between different areas of habitat

Introduced species can disrupt stable relationships in an ecosystem. 16.4 Threats to biodiversity Introduced species can disrupt stable relationships in an ecosystem. An introduced species is one that is brought to an ecosystem by humans. accidental purposeful Invasive species can have an environmental and economic impact.

Invasive species often push out native species. 16.4 Threats to biodiversity Invasive species often push out native species. kudzu (southeastern United States) Burmese python (Florida Everglades) & mice (Australia)

List reasons that biodiversity is important to humans 16.4 Threats to biodiversity List reasons that biodiversity is important to humans A loss of diversity could mean a loss of food, medicine, and economic activity

How does habitat fragmentation affect migrating bird populations? 16.4 Threats to biodiversity How does habitat fragmentation affect migrating bird populations? Birds need large areas of land or water on which to rest and feed during long migrations. If these habitats aren’t available they may not be able to complete a migration

What types of damage can introduced species cause? 16.4 Threats to biodiversity What types of damage can introduced species cause? Introduced species can disrupt ecosystems, threaten human health, and physically dominate or overtake waterways and human-made structures

How could continued fragmentation reduce biodiversity? 16.4 Threats to biodiversity How could continued fragmentation reduce biodiversity? If species are cut off from habitats they need for survival or reproduction, they could become extinct, thereby reducing biodiversity

Due Wednesday: In your Study guide Workbook Chapters 13 & 14 Chapters 15 & 16 Pages Numbers 133 1-5 134 10 135 All 137-144 145-146 1-6 147 148 7-10 150 6-13 151 1-4 152 6-9 153-154 1 & 4 Pages Numbers 155-156 All 157 1-4 158 161 5-6 162 all