Leaving a Mark on the World

• Have you ever seen very old photographs of the town or city in which you now live? Has your area changed? Perhaps there are more buildings or roads than there were many years ago. Maybe your town or city has more trees and flowers now than it had years ago. Humans, like all organisms, have an effect on their environment.

Section 6-1

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• 1. Choose an animal other than a human and describe at least two ways in which it may change its environment.

• 2. What events might have led to the changes that occurred in your town• or city?

• 3. What humans had on their environment?• positive effect have humans had on their environment? What • negative effect have

Section 6-1 Interest Grabber continued

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• 6–1 A Changing LandscapeA.Earth as an IslandB.Human ActivitiesC.Hunting and GatheringD.Agriculture

1.Domestication of Animals2.From Traditional to Modern Agriculture3.The Green Revolution

E. Industrial Growth and Urban Development

Section 6-1Section Outline

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HumanActivities

that have changed the biosphere include

may have once caused often relies on the methods of thehave resulted in

which increased

Food supply Pesticide use Monocultureuse

Hunting andgathering Agriculture

Industrial growth

Urbandevelopment

Extinctions oflarge animals

Greenrevolution

High standardof living

Increasedpollution

Section 6-1Concept Map

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Where Do Natural Resources Come From?

• Natural resources are materials that are supplied by nature. A renewable resource is one that is replaceable. A nonrenewable resource is one that cannot be replenished by natural processes. Once a nonrenewable resource is used up, it is gone forever.

Section 6-2Interest Grabber

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• 1. Examine the list of natural resources shown below. Then, classify each

• natural resource as either renewable or nonrenewable.• a. Wood• b. Fossil fuels• c. Aluminum• d. Wool• e. Gold

• 2. Describe the impact that the loss of nonrenewable resources would have on the environment.

Section 6-2Interest Grabber continued

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• 6–2 Renewable and Nonrenewable ResourcesA.The Tragedy of the CommonsB.Sustainable UseC.Land ResourcesD.Forest ResourcesE. Ocean ResourcesF. Air ResourcesG.Water Resources

Section 6-2 Section Outline

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Fish Catch World World Fish Catch per Person

Tot

al C

atch

(mill

ion

tons

)

Am

ount

of

Fis

h pe

r P

erso

n(k

ilogr

am

s)Year Year

Section 6-2 Growth of Fish Catch

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Emissions to AtmosphereNitrogen oxidesSulfur dioxide

Chemical TransformationNitric acid

Sulfuric acid

PrecipitationAcid rain, fog,snow, and mist

Dry Fallout

Condensation

particulates, gases

Industry Transportation Ore smelting Power generation

Section 6-2 Figure 6-12 The Formation of Acid Rain

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What Is Biodiversity?

• Biodiversity is the sum total of the variety of organisms in the biosphere. Sometimes humans can reduce biodiversity, which is considered a natural resource.

Section 6-3 Interest Grabber

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•1. List three ways in which other organisms have proved to be a benefit to humans.

•2. Compare biodiversity with other natural resources, such as wood and fossil fuels. Do you think biodiversity is a renewable or a nonrenewable resource? Explain your answer.

•3. What can be done to preserve the biodiversity of organisms?

Section 6-3 Interest Grabber continued

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• 6–3 BiodiversityA. The Value of BiodiversityB. Threats to BiodiversityC. Habitat Alteration and FragmentationD. Demand for Wildlife ProductsE. PollutionF. Introduced SpeciesG. Conserving

Biodiversity1. Strategies for Conservation2. Challenges in Conservation

Section 6-3 Section Outline

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Insects

BacteriaFungi

Plants

Protists Other Animals

54.4%

4.2%

18%

3.4%0.3%

19.7%

Section 6-3 Species Diversity

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Fish-Eating BirdsMagnification ofDDT Concentration

10,000,000

100,000

10,000

1,000,000

1

1000

LargeFish

Small Fish

Zooplankton

Producers

Water

Section 6-3 Figure 6-16 Biological Magnification of DDT

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How Much Should It Cost?

• You may have read that when something becomes hard to obtain, its price usually increases. Such is the case for materials like gold and diamonds, which are nonrenewable resources. Using similar thinking, some researchers believe that all the valuable services provided by a healthy ecosystem should be assigned a dollar value.

Section 6-4 Interest Grabber

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• Rank the following items in order of their importance to you. Then, next to each item, write down how much you would be willing to pay for it.

• 1. Fresh, clean drinking water• 2. Clean air to breathe• 3. An endangered plant containing a substance that can cure cancer• 4. Gas for your family car

Section 6-4 Interest Grabber continued

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• 6–4 Charting a Course for the FutureA.Ozone DepletionB.Global WarmingC.The Value of a Healthy Biosphere

Section 6-4 Section Outline

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Cover CropsLegumes growth., grasses, and othercover crops recycle soil nutrients,reduce fertilizer need, andprevent weed

Controlled GrazingBy managing graze periods and herddensities, farmers can improve nutrientcycling, increase the effectiveness ofprecipitation, and increase the carryingcapacity of pastures.

Biological Pest ControlThe use of predators and parasitesto control destructive insectsminimizes pesticide use as well ascrop damage

Contour PlowingContour plowing reduces soil erosion from land runoff. On hilly areas, plowing is done across the hill rather than straight up and down.

Crop RotationDifferent crops use and replenish different nutrients. By rotating crops, the loss of important plant nutrientsis decreased.

A B C

Yr. 1

Yr. 2

Yr. 3

Section 6-4 Sustainable Agriculture

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corn

corn

corn

alfalfa

alfalfa

alfalfa

oats

oats

alfalfa (plowed in)

Solar energy

Production of oxygen

Storage and recycling of nutrients

Regulation of climate

Purification of water and air

Storage and distribution offresh water

Food production

Nursery habits for wildlife

Detoxification of human andindustrial wasteNatural pest and disease controlManagement of soil erosionand runoff

Section 6-4 Figure 6-22 Ecosystem Services

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