1. Landforms, Water, and Natural Resources
World Geography Today
2/22/2019
Landforms, Water, and Natural Resources
Preview
Section 1: Landforms
Section 2: The Hydrosphere
Section 3: Natural Resources
Chapter Wrap-Up
Chapter 4

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

5. Forces on Earth’s Surface
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. Section 1: Landforms Weathering and Erosion Weathering Erosion
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

7. Tectonics and Surface Forces Interact
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. Section 2: The Hydrosphere
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

12. Section 2: The Hydrosphere
Floods
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

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
Importance of Soil and Forests
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.

15. Section 3: Natural Resources
Air and Water Quality
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

16. Section 3: Natural Resources
AIR POLLUTION
Effects: Acid rain, which can 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
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

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-Up Understanding the Main Ideas
World Geography Today
2/22/2019
Chapter Wrap-Up Understanding 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?
Chapter 4