Sunshine StateSTANDARDSSC.B.1.3.1: The studentidentifies forms ofenergy and explainsthat they can be meas-ured and compared.SC.B.2.3.2: The studentknows that most ofthe energy used todayis derived from burn-ing stored energycollected by organismsmillions of years ago(e.g., nonrenewablefossil fuels).SC.G.2.3.1: The studentknows that someresources are renew-able and others arenonrenewable.

Chapter 9: Natural Resources 299

KEY CONCEPT

Natural resourcessupport human activity.

THINK ABOUT

What resources do youneed the most?

Think about all the products you use at school and at home—clothing,books, video games, CDs, backpacks,and other items.

Which ones do you use the mostoften? What materials are these prod-ucts made of? Plastic? Cloth? Metal?What would you lose if one of thesematerials, such as plastic, vanishedfrom Earth overnight?

Natural resources provide materialsand energy.

For thousands of years, people have used natural resources to maketools, build cities, heat their homes, and in general make their lives morecomfortable. A is any energy source, organism, orsubstance found in nature that people use.

The four parts of the Earth system—atmosphere, hydrosphere,biosphere, and geosphere—provide all the materials needed to sustainhuman life. The atmosphere, for instance, provides the air you breatheand the rain that helps living things grow. The hydrosphere contains allof Earth’s waters in rivers, lakes, oceans, and underground. The bio-sphere and the geosphere are sources of food, fuel, clothing, and shelter.

natural resource

BEFORE, you learned

• The parts of the Earth systemshape Earth’s surface

• Life on Earth, including humanlife, depends on soil as aresource

• Forces change Earth’s surface by wearing it down and buildingit up

NOW, you will learn

• What makes a natural resourcerenewable or nonrenewable

• About benefits and costs of using fossil fuels

• How people use naturalresources in modern life

VOCABULARYUse a four-square diagramfor the term natural resourcein your notebook.

FCAT VOCABULARYrenewable resource p. 300nonrenewable resource p. 300

fossil fuel p. 302

VOCABULARYnatural resource p. 299

300 Unit 2: Earth’s Surface

However, people also know that there are costs as well as benefits inusing natural resources. For example, burning coal produces heat butalso releases smoke that pollutes the air. When forests are cut down, thesoil beneath is exposed to the air. Wind and rain can strip away valuabletopsoil, making it harder for new trees to grow. The soil can chokestreams and rivers and kill fish and other animals living in the waters.As you can see, using resources from one part of Earth’s system affectsall the other parts.

People are also concerned about saving natural resources. Someresources, such as the water in a river or the wind used to turn awindmill, are constantly being replaced. But others, such as oil, takemillions of years to form. If these resources are used faster than theyare replaced, they will run out. Today people are more aware of whichresources are renewable and which are nonrenewable.

check your reading Summarize the costs and benefits of using natural resources.

Renewable ResourcesThe charts on page 301 list some of the most common resources peopleuse in modern life. As you might have guessed, sunlight, wind, water,and trees and other plants are renewable. A is anatural resource that can be replaced in nature at about the same rateit is used.

For example, a lumber company might plant a new tree for eachmature tree it cuts down. Over time, the forest will continue to havethe same number of trees. However, if the trees are cut down fasterthan they can be replaced, even a renewable resource will run out.

Nonrenewable ResourcesA is a natural resource that exists in a fixedamount or that is used up faster than it can be replaced in nature.This means the supply of any nonrenewable resource is limited.In general, all resources produced by geologic forces—coal, natural gas,oil, uranium—are nonrenewable. These resources form over millionsof years.

Today people are using coal, oil, and natural gas much faster thanthey are forming in nature. As a result, these resources are becomingmore scarce and expensive. Many countries realize that they mustconserve their nonrenewable resources. Some, like the United States,are developing alternative energy sources, such as solar and wind energy.

check your reading Compare and contrast renewable and nonrenewable resources.

nonrenewable resource

renewable resource

NOTE TAKINGA main idea web can helpyou take notes about thecosts and benefits of usingnatural resources.

Chapter 9: Natural Resources 301

Natural Resources

Resource

Sunlight

Wind

Water

Trees and other plants

Animal waste

Common Uses

power for solar cells and bat-teries, heating of homes andbusinesses, and generatingelectricity

power to move windmills that pump water, grind grain,and generate electricity

power to generate electricity,transportation with boatsand ships, drinking andwashing

materials for furniture,clothing, fuel, dyes,medicines, paper, cardboard,and generating electricity

material for fuels

Resource

Coal

Oil

Natural gas

Uranium

Minerals and rocks

Common Uses

fuel to generate electricity,chemicals for medicines andconsumer products

fuel for cars, airplanes, andtrucks; fuel for heating and generating electricity;chemicals for plastics, syn-thetic fabrics, medicines,grease, and wax

fuel for heating, cooking,and generating electricity

fuel to generate electricity

materials for coins, jewelry,building, computer chips,lasers, household products,paint, and dyes

Renewable Resources

Nonrenewable Resources

Natural resources can be classified as renewable and nonrenewable resources.

Read the common uses of each resource. Which of these resources areused to generate electricity?

302 Unit 2: Earth’s Surface

Fossil fuels supply most of society’s energy.When you turn on the air conditioner, a computer, or a microwave oven,you may use energy from fossil fuels. Millions of people depend onthese fuels—coal, oil, and natural gas—for electricity, heat, and fuel.

A is a nonrenewable energy source formed from ancientplants and animals buried in Earth’s crust for millions of years. Theenergy in such a fuel represents a form of stored sunlight, since ancientorganisms depended on the sun. The buried organisms form layers at the bottom of oceans, ponds, and swamps. Over a long time, thismaterial is compressed and pushed deeper into Earth’s crust. High heatand pressure change it chemically into coal, oil, and natural gas.

check your reading Explain how fossil fuels are formed from ancient organisms.

fossil fuel

U.S. Energy Sources

Source: U.S. Department of Energy, 2000

Oil 41%Coal 25%Natural gas 20%Other 14%

Power lines

How does burning fossil fuels help to produce electricity?

Fossil Fuel Power Station

Fossilfuelsource

Smokestack: Byproductsof burning fuel are releasedinto the air.

Boiler: Heat from burningfossil fuels boils the waterto produce steam.

Turbine: Steamfrom the boilerturns the turbines.

Generator: Turbinesdrive generators toproduce electricity.

Water is used tocool the machinery.

Condenser: Steamcondenses into water, whichwill return to the boiler.

Fossil fuels burn easily and produce a lot of heat. They are used torun most of the power plants that generate electricity. As shown in thediagram on page 302, heat from a burning fuel is used to change waterinto steam. The steam turns a turbine. The turbine drives a generatorto produce electricity, which is carried through power lines to townsand cities. Electricity runs nearly everything in modern life, from giantfactories to the smallest light in your home.

But these resources also harm the environment. Burning fossilfuels produces excess carbon dioxide, harmful acids, and other formsof pollution. Most of this pollution comes from power plants and fossil fuels burned by cars and other vehicles.

CoalCoal is a solid fossil fuel formed underground from buried and decayedplant material. As shown below, heat and pressure determine the typeof coal formed. The hardest coal makes the best energy source. It burnshotter and much cleaner than softer coals. At one time, coal was themain source of energy in the United States.

The world’s largest coal deposits are in the United States, Russia,and China. People use surface mining and deep mining to obtain coal.In surface mines, overlying rock is stripped away to expose the coal.In deep mines, miners must go underground to dig out the coal.Most of the world’s coal is used to fuel power plants and to run factoriesthat produce steel and cement.

When burned as a fuel, however, coal produces byproducts thatpollute air and water. Also, surface mining can destroy entire landscapes.Coal dust in deep mines damages miners’ lungs. Yet reducing pollution,restoring landscapes, and protecting miners cost millions of dollars.Society faces a difficult choice—keep the cost of energy low or raisethe price to protect the environment and human health.

check your reading What is the main use of coal?

Swamp plants decay and are compressed to form peat.

Sediments bury thepeat, and rising pressureand heat change it intosoft coal.

Over millions of years,increasing pressure andheat form harder coal.

It takes the longest timeand the greatest heatand pressure to formthe hardest coal.

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Chapter 9: Natural Resources 303

reading tip

Turbine is based on the Latin turbo, whichmeans “spinning top.”Generator is based on theLatin gener -are, whichmeans “to produce.”

Oil and Natural Gas Wells

304 Unit 2: Earth’s Surface

Oil and Natural GasMost oil and natural gas is trapped underground in porous rock. Heatand pressure can push the oil and natural gas upward until they reacha layer of nonporous rock, where they collect. As shown in the illus-tration below, wells can be drilled through the nonporous rock tobring the oil and natural gas to the surface. Major oil and natural gasdeposits are found under the oceans as well as on land.

check your reading How is oil removed from layers of rock?

Recovered oil is transported by ships, trucks, and pipelines from thewells to refineries. Refineries use heat to break down the oil into its dif-ferent parts. Each part is used to make different products, from gasolineand jet fuel to cleaning supplies and plastics. Oil and natural gas burnat high temperatures, releasing energy. They are easily transported,which makes them ideal fuels to heat homes and to power vehicles.

There are costs in using oil. When ships that transport oil aredamaged, they can spill millions of gallons into the environment.These spills pollute coastlines and waterways, killing many plants and animals. Cleaning up these spills costs governments millions ofdollars each year. Even after the cleanup, some of the oil will remain in the environment for years.

Air pollution is another problem. Waste products from the burning of gasoline, jet fuels, and diesel fuels react with sunlight to produce smog—a foglike layer of air pollution. Some countrieshave passed clean air laws to reduce this pollution. Yet smog continues to be a problem in most large cities.

check your reading What are the benefits and costs of using oil?

porous sandstone

nonporous shale

Products from a Barrel of Oil

SOURCE: American Petroleum Institute, 2001

Gasoline 44%Diesel and heating fuel 26%Jet fuel 10%Other products 9%Gases 8%Asphalt 3%

Oil and gas aretrapped in porousrock layers.

Wells are drilledthrough nonporousrock to bring the oiland gas to the surface.

reading tip

Non- is a Latin prefix mean-ing “not.” Porous rock isfull of tiny cracks or holes.Therefore, nonporous rockis rock that does not havetiny cracks or holes.

Chapter 9: Natural Resources 305

Why does an oil spill do so much harm?PROCEDURE

Fill the pan about halfway with water. Using an eyedropper, carefully add 10 drops of oil in the middle of the pan. Rock the pan gently.

Observe what happens to the drops of oil over the next 2 min. Record your observations in your Science Notebook.

Place the plastic-foam ball in the oil slick, wait a few seconds, then carefullylift the ball out again. Examine it and record your observations.

WHAT DO YOU THINK?• What happened when the drops of oil came in contact with the water?

• What might happen to an animal that swims through spilled oil?

CHALLENGE Think of a way to clean up the oil slick on the water. Discuss your ideas with your teacher before you test your cleaning method.

3

2

1

Fossil FuelsFossil FuelsSKILL FOCUSModeling

MATERIALS• water• vegetable oil• large pan (at

least 22 cm)• plastic-foam ball

(about 5 cm)• eyedropper

TIME20 minutes

Fossil fuels, minerals, and plants supplymaterials for modern products.

Many of the products you use come from fossil fuels. For example, oilis broken down into different chemicals used to make plastics. Plasticmaterials can be easily shaped, colored, and formed. They are used inelectronic and computer equipment, in packaging, in cars and airplanes,and in such personal items as your shoes, toothbrush, and comb.

Minerals are found in cars and airplanes, tools, wires, computerchips, and probably your chair. Minerals such as limestone, gypsum,sand, and salt are used to make building materials and cement. In theUnited States, it takes 9,720 kilograms (20,000 lbs) of minerals everyyear to make the products used by just one person.

Plants are used to make another large group of products. For cen-turies people have used wood to build homes and to make furniture,household utensils, and different types of paper. Plants are also richsources of dyes, fibers, and medicines. The plant indigo, for example,has been used to dye fabrics since Roman times.

These products benefit people’s lives in many important ways,but they also have drawbacks. Fossil fuels must be burned to generatepower for the factories and businesses that produce these products.

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KEY CONCEPTS1. Define renewable resource

and nonrenewable resource.Give four examples of eachtype of resource.

2. List three advantages and three disadvantages of usingfossil fuels.

3. In what ways are naturalresources used to make people’slives more comfortable?

CRITICAL THINKING4. Infer Why do you think people

are willing to accept the costsas well as the benefits of usingfossil fuels?

5. Predict If supplies of coal, oil,and natural gas ran out tomor-row, what are some of the waysyour life would change?

CHALLENGE6. Apply Suppose you are lost in

the woods, miles from any cityor town. You have some driedfood and matches but no othersupplies. What natural resourcesmight you use to survive untilyou are found?

Consumer Products

Factory waste can pollute air, water, and soil. Even making computerchips can be a problem. So much water is needed to clean the chipsduring manufacture that local water supplies may be reduced.

To maintain modern life and to protect the planet, people mustuse natural resources wisely. In the next section you will read aboutways for every person to conserve resources and reduce pollution.

Thousands of everyday products are made from natural resources.

Fossil Fuels

Fossil fuels are used to make thousands of productsfrom aspirin to zippers. For example, oil-based plasticsare used to make this motocross rider’s safety helmet,suit, gloves, and boots. Gasoline powers the motorbike.

Minerals and Rocks

The U.S. Treasury uses zinc, copper, andnickel to mint over 14 billion coins a year.Gold and silver are used in special coins.

Trees and Other Plants

Each year, the United States producesabout 400 billion square feet of corrugatedcardboard used to make boxes of all sizes.