GRADE: Fourth

CONTENT STANDARD: Environmental Science

CONTENT TOPIC: Environmental Education

CONCEPT: Environmental problems may vary from community to community.

CONTENT OBJECTIVE: 4I3.00 To understand how urban and rural environmental problems vary

INSTRUCTIONAL OBJECTIVES: The learner will:

3.01 identify urban environmental problems.
3.02 identify rural environmental problems.
3.03 evaluate possible solutions to specific environmental problems.

I. Urban environmental problems
II. Rural environmental problems
III. Possible solutions to environmental problems

TN COMPONENT OF SCIENCE: Science In Society

TN GOAL:

To enable students to demonstrate attitudes toward science in solving problems and making personal decisions about issues affecting the individual, society, and the environment.

POLITICS - Basic scientific concepts should be available to all individuals enabling each to make logical decisions for themselves and others.

4.6b The risks and cost benefits must be carefully considered when developing new technology or curtailing existing technology.

BENCHMARK: Decision making processes consider the benefits and drawbacks of alternatives and the input of those affected by the decisions.

TIME REQUIRED:

Two or three instructional periods

Newspaper, magazines, pencil, paper, hydrochloric acid, limestone rock

Do you think the air inside is safer than the air outside? (response) What do you think causes air pollution inside? (response) What do you think causes air pollution outside? (response) Today we are going to learn about the differences in urban and rural environmental problems.

There are many chemicals that pollute the air. In cities, the major source of pollution is carbon monoxide. Carbon monoxide is caused most of the time by gasoline-powered motor vehicles. You might have felt some of the effects of air pollution in big cities. If you have ever visited a big city, you might have noticed that your eyes burned or that you had trouble breathing. Air pollution is a problem in big cities because cars, homes, and factories release many kinds of harmful substances, or pollutants, into the air.

Concern about air pollution has recently focused on indoor pollution. Indoor pollutants include tobacco smoke, gases from stoves, car exhaust in attached garages, and chemicals used for cleaning. Of special concern is a radioactive gas called radon. Radon comes from traces of uranium and radium that exist in practically all rocks and soil. Dangerous amounts can build up in homes, especially in basements, as the gas enters through foundation cracks and openings around pipes. Scientists think that as many as 30,000 of the 125,000 annual lung cancer deaths in the U. S. may be attributed to radon.

Sulfur dioxide is one kind of air pollutant. It is released into the air when coal is burned. The sulfur dioxide combines with water in the air, forming sulfuric acid. This weak acid becomes part of rainwater, which falls to the earth. The acid rain harms living things and also damages buildings and other structures.

Some factories that burn coal have taken steps to cut down on acid rain. These factories have placed devices called scrubbers on their smokestacks. The scrubbers remove sulfur dioxide as it is released from burning coal. (An activity to use to show the effect of acid rain can be used at this time.)

Place a few drops of hydrochloric acid on a piece of limestone. The reaction will cause a fizzing. Tell students that the bubbles form as carbon dioxide is released from the carbonate minerals in the rock. Ask students what the acid does over a period of time. (Dissolves it or wears it away) Tell students this is similar to the results of acid rain. In a few years, acid rain can have a disastrous effect on wildlife and eat away at buildings.

Trees are an important wildlife resource that do more than provide solitude and beauty. They add oxygen and water to the air. They act as windbreaks and have a cooling effect on temperatures. Their presence slows the runoff of rainwater, and their root systems hold the soil. Together, both functions prevent harmful soil erosion.

A major environmental concern of the rural community would be soil erosion. In the mid 1930''s, several years of drought followed by dust storms blew hundreds of millions of tons of soil from farm fields in the Great Plains, leaving them bare. One centimeter of soil takes 200 to 400 years to form. Yet wind and water erosion can remove soil from an area in just a few years or even overnight. To conserve soil, farmers plant crops in rows. Planting crops in this way prevents water from flowing downhill and washing away soil. Farmers also plant tall trees along their fields. How do you think this method helps conserve soil? (response)

Listed below are some class projects for evaluating possible solutions to some environmental problems:

1. Use the latest edition of The World Almanac to find some natural sources of energy and how much they are used. How much energy is produced by these sources. Would more energy be used in a city or in rural area?

2. Natural resources such as air, land, and water can become polluted. Find out about potential pollution sources in your community. Make a list of these sources. Find out how your community helps control pollution. Have the mayor or other appropriate city or county official address the class.

3. List four substances that are sometimes indoor air pollutants and give one possible source for each.

4. Make a list of alternative energy sources. Next to each source write advantages and disadvantages.

With your neighbor, list two urban environmental problems and two rural environmental problems and a possible solution for each. Share these with the class.

This is the time this file has been accessed since 07/01/97.

The University of Tennessee at Martin is not responsible for the information or views expressed here.

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