humans and the environment chapter 22 table of contents section 1 an interconnected planet section 2...
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Humans and the EnvironmentChapter 22
Table of Contents
Section 1 An Interconnected Planet
Section 2 Environmental Issues
Section 3 Environmental Solutions
Section 1 An Interconnected PlanetChapter 22
Objectives
• Explain the importance of the study of environmental science.
• Describe Earth’s major layers.
• Explain the natural functions of the ozone layer and greenhouse effect.
• Summarize the ways in which biologists measure biodiversity.
• Discuss the value of biodiversity.
Section 1 An Interconnected PlanetChapter 22
Earth’s Layers
• Earth’s geosphere, hydrosphere, and atmosphere are interconnected in many ways.
• Together, these parts make up the biosphere, the part of the Earth where life exists.
Section 1 An Interconnected PlanetChapter 22
Earth’s Layers, continued
• Atmosphere– Important parts of the atmosphere are greenhouse
gases, which trap heat on Earth, and the ozone layer, which shields Earth from UV radiation.
Section 1 An Interconnected PlanetChapter 22
Earth’s Layers, continued
• Climate and Atmosphere– The atmosphere’s ability to trap heat in this way is
called the greenhouse effect.
Chapter 22
The Greenhouse Effect
Section 1 An Interconnected Planet
Section 1 An Interconnected PlanetChapter 22
Earth’s Layers, continued
• Hydrosphere– A very small portion of the hydrosphere is fresh
water, and much of this fresh water is not easily usable.
Section 1 An Interconnected PlanetChapter 22
Earth’s Layers, continued
• Geosphere– The geosphere exchanges materials with the
atmosphere, hydrosphere, and biosphere.
Section 1 An Interconnected PlanetChapter 22
Earth’s Layers, continued
• Biosphere– The biosphere includes all parts of Earth where
life exists.
Section 1 An Interconnected PlanetChapter 22
Biodiversity
• Biodiversity refers to the variety of life found in an area.
Section 1 An Interconnected PlanetChapter 22
Biodiversity, continued
• Measuring Biodiversity– Biodiversity can be measured in different ways,
including by species richness, species evenness, and genetic diversity.
Section 1 An Interconnected PlanetChapter 22
Biodiversity, continued
• Valuing Biodiversity– Biodiversity is valued for various reasons.
Section 2 Environmental IssuesChapter 22
Objectives• Describe major consequences of air pollution.
• Relate air pollution to effects on global climate.
• Describe how chemical pollutants may undergo the process of biological magnification.
• Identify the primary causes of modern extinctions.
• Explain why extinctions and ecosystem disruption are of concern to humans.
• Relate human resource use to its impacts on ecosystems.
Section 2 Environmental IssuesChapter 22
Pollution
• Over a short time period, human activities have affected global ecosystems in ways that harm humans and other species.
• Human impacts range from local pollution to global change in ecosystems.
Section 2 Environmental IssuesChapter 22
Pollution, continued
• Ozone Thinning– Industrial chemicals called chlorofluorocarbons
(CFCs) act as catalysts in chemical reactions that break down O3 molecules in the ozone layer.
– Most countries have banned CFCs, and the ozone layer seems to be recovering.
Chapter 22
Ozone “Hole” Over Antarctica
Section 2 Environmental Issues
Chapter 22
Click below to watch the Visual Concept.
Visual Concept
Ozone and Ecosystems
Section 2 Environmental Issues
Section 2 Environmental IssuesChapter 22
Pollution, continued
• Global Warming
– The correlation of increasing atmospheric CO2 and rising global temperature suggests a cause-and-effect relationship.
– Considering several types of evidence, many scientists have concluded that increased CO2 levels have caused warmer surface temperatures on Earth.
Chapter 22
Click below to watch the Visual Concept.
Visual Concept
Global Warming
Section 2 Environmental Issues
Section 2 Environmental IssuesChapter 22
Pollution, continued
• Acid Precipitation– Certain air pollutants cause acid precipitation,
which harms or kills many organisms.
Section 2 Environmental IssuesChapter 22
Pollution, continued
• Land and Water Pollution– The release of toxic chemicals, such as DDT, into
the biosphere can impact ecosystems in many ways, especially when chemicals undergo biological magnification.
Chapter 22
Biological Magnification of DDT
Section 2 Environmental Issues
Chapter 22
Click below to watch the Visual Concept.
Visual Concept
Biological Magnification of Toxins
Section 2 Environmental Issues
Section 2 Environmental IssuesChapter 22
Ecosystem Disruption, continued
• Extinction– Human impacts on the environment are causing
an increasing number of extinctions. – Important causes of extinctions are habitat
destruction, the transfer of invasive species to new habitats, harvesting, and hunting.
– This loss of species has both known and unknown effects on ecosystems.
Section 2 Environmental IssuesChapter 22
Ecosystem Disruption, continued
• Ecosystem Imbalances– Species such as the sea otter that affect many
other species in a community are called keystone species.
Section 2 Environmental IssuesChapter 22
Human Resource Use
• Current levels of human resource use are probably not sustainable.
Chapter 22
World Population Growth Patterns
Section 2 Environmental Issues
Section 3 Environmental SolutionsChapter 22
Objectives
• State the goals of conservation and restoration biology.
• Describe examples of efforts to protect species and their habitats.
• Summarize international strategies for protecting entire ecosystems.
• Discuss the roles of governments and laws in addressing environmental problems.
• List several things that individuals can do to help solve environmental problems.
Section 3 Environmental SolutionsChapter 22
Conservation and Restoration Biology
• Conservation biologists are concerned with identifying and maintaining ecosystems, while restoration biologists are usually involved with repairing badly damaged ecosystems.
Section 3 Environmental SolutionsChapter 22
Conservation and Restoration Biology, continued
• Species and Habitats– A bioindicator is a species that is especially
sensitive to ecological change.
Section 3 Environmental SolutionsChapter 22
Conservation and Restoration Biology, continued
• Case Study: Saving the Whooping Crane– Populations of many migratory birds, such as the
whooping crane, are in decline because of human activities.
– However, some populations are recovering as a result of legal protection, breeding programs, habitat restoration, and international partnerships.
Section 3 Environmental SolutionsChapter 22
Protecting Ecosystems
• Biodiversity Hotspots– International and cooperative efforts to preserve
habitat and prevent extinctions include identifying biodiversity hotspots, making debt-for-nature swaps, and promoting ecotourism.
Section 3 Environmental SolutionsChapter 22
Governments and Laws
• Environmental problems can be addressed through the efforts of governments and laws.
Section 3 Environmental SolutionsChapter 22
Private Efforts and Cooperation
• Environmental problems can be addressed through the combined efforts of governments, scientists, businesses, and individuals.
Section 3 Environmental SolutionsChapter 22
Conservation Case Study: The Everglades
• The Everglades restoration project is the most ambitious ecosystem-wide restoration project attempted in the United States.
Section 3 Environmental SolutionsChapter 22
Your Role in the Environment
• No one can predict our environment’s future, but it is clear that individuals can make a difference in its fate.
• Thus, it is important for you, as an individual, to understand your role in the environment and to take responsibility for that role.
Chapter 22
Click below to watch the Visual Concept.
Visual Concept
Conservation
Section 3 Environmental Solutions