1. End Show Slide 1 of 21 Copyright Pearson Prentice Hall Biology

2. End Show Slide 2 of 21 Copyright Pearson Prentice Hall 6-1 A Changing Landscape

3. End Show 6-1 A Changing Landscape Slide 3 of 21 Copyright Pearson Prentice Hall Earth as an Island All organisms on Earth share a limited resource base and depend on it for their long-term survival. To protect these resources, we need to understand how humans interact with the biosphere.

4. End Show 6-1 A Changing Landscape Slide 4 of 21 Copyright Pearson Prentice Hall Human Activities What types of human activities can affect the biosphere?

5. End Show 6-1 A Changing Landscape Slide 5 of 21 Copyright Pearson Prentice Hall Human Activities Some human activities that affect the biosphere include: hunting and gathering agriculture industry urban development

6. End Show 6-1 A Changing Landscape Slide 6 of 21 Copyright Pearson Prentice Hall Agriculture The Green Revolution The green revolution was an effort in the mid- twentieth century to increase global food production through modern plant breeding and agricultural techniques. Over the last 50 years, the green revolution has helped world food production double.

7. End Show 6-1 A Changing Landscape Slide 7 of 21 Copyright Pearson Prentice Hall Agriculture Challenges for the Future While increasing world food supplies, modern agriculture has created ecological challenges. For example: Monoculture leads to problems with insect pests and diseases. Finding enough water for irrigation is difficult.

8. End Show 6-1 A Changing Landscape Slide 8 of 21 Copyright Pearson Prentice Hall Industrial Growth and Urban Development Human society and its impact on the biosphere were transformed by the Industrial Revolution, which added machines and factories to civilization.

9. End Show 6-1 A Changing Landscape Slide 9 of 21 Copyright Pearson Prentice Hall

10. End Show 6-1 A Changing Landscape Slide 10 of 21 Copyright Pearson Prentice Hall Industrial Growth and Urban Development The energy to power machinery comes mostly from fossil fuels—coal, oil, and natural gas. Suburban growth consumes farmland and stresses native plants and animals.

11. End Show - or - Continue to: Click to Launch: Slide 11 of 21 Copyright Pearson Prentice Hall 6-1

12. End Show Slide 12 of 21 Copyright Pearson Prentice Hall 6-1 Today, the most important source of environmental change on the planet is a.the green revolution. b.wild plants. c.humans. d.abiotic factors.

13. End Show Slide 13 of 21 Copyright Pearson Prentice Hall 6-1 The practice of planting a single crop in the same place year after year is called a.uniculture. b.monoculture. c.the green revolution. d.plant breeding.

14. End Show Slide 14 of 21 Copyright Pearson Prentice Hall 6-1 One problem with modern agriculture is that a.chemical fertilizers don’t work. b.chemical pesticides can damage beneficial insects. c.it has decreased world food production. d.new varieties of plants require little water.

15. End Show Slide 15 of 21 Copyright Pearson Prentice Hall 6-1 One impact of early hunting and gathering groups in North America might have been a.changing the climate from very cold to much warmer. b.the elimination of forests. c.a mass extinction of large mammals about 12,000 years ago. d.the development of large civilizations in Central and South America.

16. End Show Slide 16 of 21 Copyright Pearson Prentice Hall 6-1 Most of the energy for industry comes from a.the sun. b.nuclear power plants. c.moving water. d.fossil fuels.

17. End Show Slide 17 of 21 Copyright Pearson Prentice Hall 6-2 Renewable and Nonrenewable Resources

18. End Show Slide 18 of 21 Copyright Pearson Prentice Hall Classifying Resources –How are environmental resources classified?

19. End Show Slide 19 of 21 Copyright Pearson Prentice Hall Classifying Resources –Environmental goods and services may be classified as either renewable or nonrenewable.

20. End Show Slide 20 of 21 Copyright Pearson Prentice Hall Classifying Resources Renewable resources can regenerate if they are alive, or can be replenished by biochemical cycles if they are nonliving. A tree is an example of a renewable resource because a new tree can be planted in place of an old tree that dies or is cut down.

21. End Show Slide 21 of 21 Copyright Pearson Prentice Hall Classifying Resources A nonrenewable resource is one that cannot be replenished by natural processes. Fossil fuels such as coal, oil, and natural gas are nonrenewable resources. Once these fuels are depleted, they are gone forever.

22. End Show Slide 22 of 21 Copyright Pearson Prentice Hall Sustainable Development –What effects do human activities have on natural resources?

23. End Show Slide 23 of 21 Copyright Pearson Prentice Hall Sustainable Development –Human activities can affect the quality and supply of renewable resources such as land, forests, fisheries, air, and fresh water.

24. End Show Slide 24 of 21 Copyright Pearson Prentice Hall Sustainable Development Sustainable development is a way of using natural resources without depleting them, and of providing for human needs without causing long-term environmental harm.

25. End Show Slide 25 of 21 Copyright Pearson Prentice Hall Land Resources Land provides space for human communities and raw materials for industry. Land also includes the soils in which crops are grown. If managed properly, soil is a renewable resource.

26. End Show Slide 26 of 21 Copyright Pearson Prentice Hall Land Resources Food crops grow best in fertile soil—a mixture of sand, clay, rock particles, and humus (material from decayed organisms).

27. End Show Slide 27 of 21 Copyright Pearson Prentice Hall Land Resources Soil erosion is the wearing away of surface soil by water and wind. Plowing the land removes the roots that hold the soil in place, and therefore increases the rate of soil erosion.

28. End Show Slide 28 of 21 Copyright Pearson Prentice Hall Land Resources Desertification is the process by which productive areas are turned into deserts. Desertification is caused by a combination of farming, overgrazing, and drought.

29. End Show Slide 29 of 21 Copyright Pearson Prentice Hall Land Resources A variety of sustainable- development practices can prevent problems such as soil erosion and desertification.

30. End Show Slide 30 of 21 Copyright Pearson Prentice Hall Land Resources –Sustainable-development practices include: contour plowing—fields are plowed across the slope of the land to reduce erosion leaving stems and roots of the previous year's crop in place to help hold the soil planting a field with rye rather than leaving it unprotected from erosion

31. End Show Slide 31 of 21 Copyright Pearson Prentice Hall Forest Resources Earth’s forests are an important resource for the products they provide and for the ecological functions they perform.

32. End Show Slide 32 of 21 Copyright Pearson Prentice Hall Forest Resources Forests: provide wood for products and fuel. remove carbon dioxide and produce oxygen. store nutrients. provide habitats and food for organisms. moderate climate. limit soil erosion. protect freshwater supplies.

33. End Show Slide 33 of 21 Copyright Pearson Prentice Hall Forest Resources Whether a forest can be considered a renewable resource depends partly on the type of forest. Temperate forests of the Northeast are renewable because they have been logged and have grown back naturally. Old-growth forests, such as those in Alaska and the Pacific Northwest, are nonrenewable because it takes centuries to produce them.

34. End Show Slide 34 of 21 Copyright Pearson Prentice Hall Forest Resources –Deforestation Loss of forests, or deforestation, has several effects: Erosion can wash away nutrients in the topsoil. Grazing or plowing can permanently change local soils and microclimates, which prevents the regrowth of trees.

35. End Show Slide 35 of 21 Copyright Pearson Prentice Hall Forest Resources –Forest Management Mature trees can be harvested selectively to promote the growth of younger trees and preserve the forest ecosystem. Tree geneticists are breeding new, faster-growing trees that produce high- quality wood.

36. End Show Slide 36 of 21 Copyright Pearson Prentice Hall Fishery Resources Fishes and other animals that live in water are a valuable source of food.

37. End Show Slide 37 of 21 Copyright Pearson Prentice Hall Fishery Resources –Overfishing Overfishing, or harvesting fish faster than they can be replaced by reproduction, has greatly reduced the amount of fish in parts of the world’s oceans. Until recently, fisheries seemed to be a renewable resource, but overfishing has limited that resource.

38. End Show Slide 38 of 21 Copyright Pearson Prentice Hall Fishery Resources –Sustainable Development The U.S. National Marine Fisheries Service has issued guidelines that specify how many fish, and of what size, can be caught in various parts of the oceans. The regulations have helped fish populations recover.

39. End Show Slide 39 of 21 Copyright Pearson Prentice Hall Fishery Resources

40. End Show Slide 40 of 21 Copyright Pearson Prentice Hall Fishery Resources

41. End Show Slide 41 of 21 Copyright Pearson Prentice Hall Fishery Resources –Aquaculture The raising of aquatic animals for human consumption, which is called aquaculture, is also helping to sustain fish resources.

42. End Show Slide 42 of 21 Copyright Pearson Prentice Hall Air Resources The condition of the air affects people’s health. Smog is a mixture of chemicals that occurs as a gray-brown haze in the atmosphere. Smog is: due to automobile exhausts and industrial emissions. considered a pollutant because it threatens people’s health.

43. End Show Slide 43 of 21 Copyright Pearson Prentice Hall Air Resources A pollutant is a harmful material that can enter the biosphere through the land, air, or water. The burning of fossil fuels can release pollutants that cause smog and other problems in the atmosphere.

44. End Show Slide 44 of 21 Copyright Pearson Prentice Hall Air Resources Strict automobile emissions standards and clean-air regulations have improved air quality in many cities, but air pollution is still a problem.

45. End Show Slide 45 of 21 Copyright Pearson Prentice Hall Air Resources Many combustion processes release nitrogen and sulfur compounds into the atmosphere. These compounds combine with water vapor to form acid rain.

46. End Show Slide 46 of 21 Copyright Pearson Prentice Hall Formation of Acid Rain Air Resources Emissions to Atmosphere Nitrogen oxides Sulfur dioxide Chemical Transformation Nitric acid Sulfuric acid Condensation Dry Fallout Particulates Gases Precipitation Acid rain, fog, snow, and mist Industry Transportation Ore smelti ng Power generat ion

47. End Show Slide 47 of 21 Copyright Pearson Prentice Hall Air Resources Acid rain kills plants by damaging their leaves and changing the chemistry of soils and standing-water ecosystems. Acid rain may dissolve and releases toxic elements, such as mercury, from the soil, freeing the elements to enter other portions of the biosphere.

48. End Show Slide 48 of 21 Copyright Pearson Prentice Hall Freshwater Resources Americans use billions of liters of fresh water daily for everything from drinking and washing to watering crops and making steel. Although water is a renewable resource, the total supply of fresh water is limited and is threatened by pollution.

49. End Show Slide 49 of 21 Copyright Pearson Prentice Hall Forest Resources Sources of pollution include: improperly discarded chemicals that enter streams and rivers. wastes discarded on land that seep through soil and enter underground water supplies. domestic sewage containing compounds that encourage growth of algae and bacteria. sewage containing microorganisms that spread disease.

50. End Show Slide 50 of 21 Copyright Pearson Prentice Hall Freshwater Resources –Sustainable Use of Water One way to ensure the sustainable use of water is to protect the natural systems involved in the water cycle that help purify water. These include: wetlands forests other vegetation

51. End Show Slide 51 of 21 Copyright Pearson Prentice Hall Freshwater Resources Also, by conserving water in: home industry agriculture

52. End Show Slide 52 of 21 Copyright Pearson Prentice Hall 6-2

53. End Show Slide 53 of 21 Copyright Pearson Prentice Hall 6-2 –Which of the following is a nonrenewable resource? trees grasses used by grazing animals oxygen in the air fossil fuels

54. End Show Slide 54 of 21 Copyright Pearson Prentice Hall 6-2 –Which of the following is a sustainable-use strategy that can help prevent desertification? contour plowing protecting wetlands aquaculture selective harvesting of trees

55. End Show Slide 55 of 21 Copyright Pearson Prentice Hall 6-2 –The advantage of sustainable development is that it provides for human needs without depleting natural resources. produces additional fossil fuels. protects wildlife from hunters and other threats. is a natural process that regulates itself.

56. End Show Slide 56 of 21 Copyright Pearson Prentice Hall 6-2 –A mixture of chemicals that occurs as a haze in the atmosphere is known as smog. acid rain. particulates. fog.

57. End Show Slide 57 of 21 Copyright Pearson Prentice Hall 6-2 –Plowing the land removes the roots that hold the soil in place and increases the rate of pollution. soil erosion. deforestation. soil formation.

58. End Show Slide 58 of 21 Copyright Pearson Prentice Hall 6-3 Biodiversity

59. End Show Slide 59 of 21 Copyright Pearson Prentice Hall The Value of Biodiversity Biological diversity, or biodiversity, is the sum total of the genetically based variety of all organisms in the biosphere. Ecosystem diversity includes the variety of habitats, communities, and ecological processes in the living world.

60. End Show Slide 60 of 21 Copyright Pearson Prentice Hall The Value of Biodiversity Species diversity is the number of different species in the biosphere. Genetic diversity is the sum total of all the different forms of genetic information carried by all organisms living on Earth today.

61. End Show Slide 61 of 21 Copyright Pearson Prentice Hall The Value of Biodiversity –Why is biodiversity important?

62. End Show Slide 62 of 21 Copyright Pearson Prentice Hall The Value of Biodiversity –Biodiversity is one of Earth's greatest natural resources. –Species of many kinds have provided us with foods, industrial products, and medicines—including painkillers, antibiotics, heart drugs, antidepressants, and anticancer drugs.

63. End Show Slide 63 of 21 Copyright Pearson Prentice Hall Threats to Biodiversity –What are the current threats to biodiversity?

64. End Show Slide 64 of 21 Copyright Pearson Prentice Hall Threats to Biodiversity –Human activity can reduce biodiversity by: altering habitats hunting species to extinction introducing toxic compounds into food webs introducing foreign species to new environments

65. End Show Slide 65 of 21 Copyright Pearson Prentice Hall Threats to Biodiversity Extinction occurs when a species disappears from all or part of its range. A species whose population size is declining in a way that places it in danger of extinction is called an endangered species. As the population of an endangered species declines, the species loses genetic diversity.

66. End Show Slide 66 of 21 Copyright Pearson Prentice Hall Habitat Alteration When land is developed, natural habitats may be destroyed. Development often splits ecosystems into pieces, a process called habitat fragmentation. The smaller a species’ habitat is, the more vulnerable the species is to further disturbance.

67. End Show Slide 67 of 21 Copyright Pearson Prentice Hall Demand for Wildlife Products Throughout history, humans have pushed some animal species to extinction by hunting them for food or other products. Today, in the U.S., endangered species are protected from hunting.

68. End Show Slide 68 of 21 Copyright Pearson Prentice Hall Demand for Wildlife Products The Convention on International Trade in Endangered Species, CITES, bans international trade in products derived from endangered species.

69. End Show Slide 69 of 21 Copyright Pearson Prentice Hall Pollution Many forms of pollution can threaten biodiversity. One of the most serious problems occurs when toxic compounds accumulate in the tissues of organisms. DDT, one of the first pesticides, is a good example of this.

70. End Show Slide 70 of 21 Copyright Pearson Prentice Hall Pollution For a long time DDT was considered harmless, and it drained into rivers and streams in low concentrations. However, DDT has two hazardous properties: It is nonbiodegradable, which means that it cannot be broken down by organisms. Once DDT is picked up by organisms, it cannot be eliminated from their bodies.

71. End Show Slide 71 of 21 Copyright Pearson Prentice Hall Pollution When DDT enters food webs, it undergoes biological magnfication. In biological magnification, concentrations of a harmful substance increase in organisms at higher trophic levels in a food chain or food web. In 1962, biologist Rachel Carson wrote Silent Spring, which alerted people to the dangers of biological magnification.

72. End Show Slide 72 of 21 Copyright Pearson Prentice Hall Pollution Magnification of DDT Concentration

73. End Show Slide 73 of 21 Copyright Pearson Prentice Hall Pollution Magnification of DDT Concentration

74. End Show Slide 74 of 21 Copyright Pearson Prentice Hall Pollution Magnification of DDT Concentration

75. End Show Slide 75 of 21 Copyright Pearson Prentice Hall Pollution Magnification of DDT Concentration

76. End Show Slide 76 of 21 Copyright Pearson Prentice Hall Pollution Magnification of DDT Concentration

77. End Show Slide 77 of 21 Copyright Pearson Prentice Hall Pollution Magnification of DDT Concentration

78. End Show Slide 78 of 21 Copyright Pearson Prentice Hall Pollution The widespread use of DDT threatened populations of many animals—especially fish-eating birds like the bald eagle—with extinction. By the early 1970s, DDT was banned in the U.S. and in most other industrialized countries; as a result, affected bird populations have recovered.

79. End Show Slide 79 of 21 Copyright Pearson Prentice Hall Introduced Species Another threat to biodiversity comes from plants and animals that humans transport around the world either accidentally or intentionally. Invasive species are introduced species that reproduce rapidly because their new habitat lacks the predators that would control their population.

80. End Show Slide 80 of 21 Copyright Pearson Prentice Hall Introduced Species Hundreds of invasive species—including zebra mussels in the Great Lakes and the leafy spurge across the Northern Great Plains— are already causing ecological problems in the United States.

81. End Show Slide 81 of 21 Copyright Pearson Prentice Hall Conserving Biodiversity Conservation is the wise management of natural resources, including the preservation of habitats and wildlife.

82. End Show Slide 82 of 21 Copyright Pearson Prentice Hall Conserving Biodiversity Strategies for Conservation Many conservation efforts are aimed at managing individual species to keep them from becoming extinct.

83. End Show Slide 83 of 21 Copyright Pearson Prentice Hall Conserving Biodiversity –What is the goal of conservation biology?

84. End Show Slide 84 of 21 Copyright Pearson Prentice Hall Conserving Biodiversity –Conservation efforts focus on protecting entire ecosystems as well as single species. –Protecting an ecosystem will ensure that the natural habitats and the interactions of many different species are preserved at the same time.

85. End Show Slide 85 of 21 Copyright Pearson Prentice Hall Conserving Biodiversity –Conservation Challenges Protecting resources for the future can require people to change the way they earn their living today. Conservation regulations must be informed by solid research and must try to maximize benefits while minimizing economic costs.

86. End Show Slide 86 of 21 Copyright Pearson Prentice Hall 6-3

87. End Show Slide 87 of 21 Copyright Pearson Prentice Hall 6-3 –The type of biodiversity that includes the inheritance information carried by the Earth’s organisms is called biological magnification. ecological diversity. genetic diversity. species diversity.

88. End Show Slide 88 of 21 Copyright Pearson Prentice Hall 6-3 –Populations of invasive species tend to decrease. increase rapidly. remain constant. increase, then decrease.

89. End Show Slide 89 of 21 Copyright Pearson Prentice Hall 6-3 –The wise management of natural resources, including the preservation of habitats and wildlife, is known as biodiversity. conservation. habitat alteration. ecosystem diversity.

90. End Show Slide 90 of 21 Copyright Pearson Prentice Hall 6-3 –By focusing on protecting specific ecosystems, biologists hope to preserve global biodiversity. biological magnification. invasive species. habitat fragmentation.

91. End Show Slide 91 of 21 Copyright Pearson Prentice Hall 6-3 –In a food pyramid, biological magnification results in the increased amount of a toxic substance in organisms at the lowest level. increased amount of a toxic substance in organisms at the highest level. decreased number of levels in the food pyramid. increased amount of a toxic substance in the surrounding air or water.

92. End Show Slide 92 of 21 Copyright Pearson Prentice Hall 6-4 Charting a Course for the Future

93. End Show Slide 93 of 21 Copyright Pearson Prentice Hall Ozone Depletion What are two types of global change of concern to biologists?

94. End Show Slide 94 of 21 Copyright Pearson Prentice Hall 6-4 Charting a Course for the Future Researchers are gathering data to monitor and evaluate the effects of human activities on important systems in the biosphere. Two of these systems are: the ozone layer high in the atmosphere the global climate system

95. End Show Slide 95 of 21 Copyright Pearson Prentice Hall Ozone Depletion Exposure to UV can: cause cancer damage eyes decrease organisms' resistance to disease damage plant leaf tissue and phytoplankton in the oceans

96. End Show Slide 96 of 21 Copyright Pearson Prentice Hall Ozone Depletion Early Evidence In the 1970s, scientists discovered a hole in the ozone layer over Antarctica. After it was first discovered, the ozone hole grew larger.

97. End Show Slide 97 of 21 Copyright Pearson Prentice Hall

98. End Show Slide 98 of 21 Copyright Pearson Prentice Hall Ozone Depletion One Solution CFCs (chlorofluorocarbons) were once widely used: as propellants in aerosol cans as coolant in refrigerators, freezers, and air conditioners in the production of plastic foams The U.S. and other nations began reducing the use of CFCs in 1987, and eventually banned them.

99. End Show Slide 99 of 21 Copyright Pearson Prentice Hall Ozone Depletion

100. End Show Slide 100 of 21 Copyright Pearson Prentice Hall Global Climate Change The term used to describe the increase in the average temperature of the biosphere is global warming. One sign of global warming is melting polar ice.

101. End Show Slide 101 of 21 Copyright Pearson Prentice Hall Global Climate Change

102. End Show Slide 102 of 21 Copyright Pearson Prentice Hall Global Climate Change Evidence of Global Warming The geological record shows that Earth’s climate has changed repeatedly during its history.

103. End Show Slide 103 of 21 Copyright Pearson Prentice Hall

104. End Show Slide 104 of 21 Copyright Pearson Prentice Hall

105. End Show Slide 105 of 21 Copyright Pearson Prentice Hall The Value of a Healthy Biosphere

106. End Show Slide 106 of 21 Copyright Pearson Prentice Hall The Value of a Healthy Biosphere

107. End Show Slide 107 of 21 Copyright Pearson Prentice Hall 6-4

108. End Show Slide 108 of 21 Copyright Pearson Prentice Hall 6-4 An increase in the average temperature of the biosphere is called the greenhouse effect. global warming. ozone depletion. climate control.

109. End Show Slide 109 of 21 Copyright Pearson Prentice Hall 6-4 The geological record indicates that Earth’s climate has remained essentially the same throughout history. been constant until humans have influenced the environment. changed dramatically every 150 years. repeatedly changed over its history.

110. End Show Slide 110 of 21 Copyright Pearson Prentice Hall 6-4 A possible effect of global warming is extinction of organisms in areas where they once thrived. an increase in global surface temperature of 20 Celsius degrees. a sharp decrease in the temperature of the waters off the coast of California. complete elimination of the protective ozone layer in the atmosphere.

111. End Show Slide 111 of 21 Copyright Pearson Prentice Hall 6-4 Depletion of Earth’s protective ozone layer results in a decrease in the amount of heat that reaches the surface. a decrease in the amount of UV radiation that reaches the surface. an increase in the amount of rainfall. an increase in the amount of UV radiation that reaches the surface.

112. End Show Slide 112 of 21 Copyright Pearson Prentice Hall 6-4 The most likely cause of ozone depletion is the addition of carbon dioxide to the atmosphere. increase in UV radiation from the sun. addition of chemicals developed for use in refrigeration and aerosol cans. increase in the amount of smog produced by automobiles.