Landforms, Water, and Natural Resources

1. Landforms, Water, and Natural Resources Preview Section 1:Landforms Section 2:The Hydrosphere Section 3:Natural Resources Chapter Wrap-Up

2. Section 1: Landforms Read to Discover • What physical processes inside Earth built up the land? • What physical processes on Earth’s surface wear down the land? • How do these physical processes interact to create landforms?

3. Section 1: Landforms Plate Tectonics Earth’s crust is made up of moving plates, which spread, collide, and slide laterally past one another. Spreading plates form oceanic ridges undersea and rift valleys on land. Colliding plates cause trenches and volcanoes undersea and mountains on land. Plates sliding laterally cause fractures and earthquakes.

4. Section 1: Landforms Question By which processes do weathering and erosion wear down the land?

5. Section 1: Landforms Forces on Earth’s Surface Weathering and erosion shape the land. Weathering—Slow and hard to detect; includes chemical and physical processes Erosion—Movement of surface material by water, wind, and ice; wears down land

6. Erosion Weathering Physical Processes • Heating and cooling • Freezing and thawing • Tree roots Chemical Processes • Substances in air and water Water • Rainfall • Rivers • Waves Wind • Abrasion • Move from one place to another Ice • Glaciers Section 1: Landforms Weathering and Erosion

7. Section 1: Landforms Tectonics and Surface Forces Interact Landforms are created through a combination of forces. For example, a mountain range is formed by tectonics and then weathered and eroded to create valleys, alluvial fans, deltas, and other landforms.

8. Section 2: The Hydrosphere Read to Discover • In what forms and where do we find water on Earth? • What are the causes and effects of floods?

9. Section 2: The Hydrosphere Forms of Water • Saltwater—97 percent of world’s water • Freshwater—most frozen in ice caps; less than 1 percent in vapor and liquid form Where Liquid Freshwater Is Found: • Surface Water—in headwaters, tributaries, rivers, lakes, estuaries, wetlands • Groundwater—stored in soil and water table

10. Section 2: The Hydrosphere Question What roles do evaporation, condensation, and precipitation play in the hydrologic cycle?

11. Condensation: As water vapor rises, it forms droplets. Precipitation: Droplets may become heavy enough to fall as rain, snow, or hail. Evaporation: Energy transforms water into vapor. Surface Water Section 2: The Hydrosphere

12. Section 2: The Hydrosphere • Causes—Rivers carrying more water than the stream channels can hold; heavy rains, sudden snow melts; human activity may contribute • Effects—Erosion, loss of vegetation and livestock, death, spread of disease, and property destruction Floods

13. Section 3: Natural Resources Read to Discover • Why are soil and forests important resources? • What are the concerns about water quality and air quality? • What are some of the ways minerals are used? • What are the main energy resources, and how are they used?

14. Section 3: Natural Resources • Soil and forests are renewable resources. Natural processes continuously replace them. • Soil is crucial for plant life and production of food for humans and for other animals. • Forests protect soil from erosion, provide species habitats, and yield useful products, such as wood, paper, food, medicines, oils, and rubber. Importance of Soil and Forests

15. Section 3: Natural Resources • Air Pollution—Threatens air supply; dangerous to health of humans, animals, and plants; creates acid rain, which can damage trees and kill fish; damages the ozone layer, which absorbs harmful ultraviolet radiation; may contribute to global warming • Water Pollution—Threatens clean water supply; contributes to shortages Air and Water Quality

16. Section 3: Natural Resources AIR POLLUTION Effects:Acid rain, whichcan damage trees and kill fish;ozone layer damage; threat to human health; may contribute to global warming Causes:Factories and automobiles burn chemicals, releasing smoke and fumes into the atmosphere.

17. Section 3: Natural Resources • Minerals are solid substances that come out of the ground, such as metals, rocks, and salt. • Minerals are used in many processes and products, including construction, jewelry, and manufacturing. • Items made from minerals include building materials, airplanes, cans, and glass. Examples: Quartz, limestone, aluminum, gold, gemstones Minerals

18. Section 3: Natural Resources Energy resources are nonrenewable and include fossil fuels—coal, natural gas, and petroleum—and uranium. Uses: • Uranium—Energy for nuclear power • Coal—Heat source; power for steam engines, mills, electricity generation; dye making • Petroleum—Lamp fuel; gasoline; diesel and heating fuel; asphalt; petrochemicals • Natural Gas—Home and industrial heating; fuel

19. Chapter Wrap-UpUnderstanding the Main Ideas • What are the three types of movements possible at plate boundaries? • What are the two physical processes that wear down landforms on Earth’s surface? • What process makes some inland lakes salty? • What are two short-term effects of air pollution? • What is a major drawback of using coal as an energy source?