- To define the terms buffer strip, terraces and contour farming.
- To apply the skills of observation to interpret visual materials
as sources of information.
- To explore the causes and effects of soil erosion and water pollution.
Students will examine an aerial photograph of a terraced farm field.
The clue questions will introduce students to the terms terrace, buffer
strip and contour farming. In Iowa, terraces and buffer strips are
used to prevent the run-off that destroys topsoil and pollutes streams
During the follow-up activity students will be introduced to terracing
as a farming practice throughout the world. In many locations and climates
for thousands of years, people have farmed the slopes of mountains and
hills by creating terraces.
As an application of these concepts, students will make observations
City, an important and famous painting by Grant
Wood. Students should apply sound principles of contour farming when
observing the painting. Then they will draw their own version of the painting
by adding contour farming with terraces and buffer strips.
- Introduce the terms cause and effect. Discuss the fact that for every
event or decision, there are multiple effects. Provide examples such
as the following:
||Flooding along rivers and streams
|Choosing to smoke cigarettes
||Increased risk of lung cancer
|Working hard on school assignments
- In addition to initial effects, there are also ripple effects. For
example, heavy rains result in flooding along rivers and streams that
in turn, results in evacuation of people living along the streams, etc.
- Distribute to teams of students a blank copy of the Decision
Wheel. Have students write the words "Soil Erosion and Pollution"
in the center of the wheel.
- Using online resources students will identify
the consequences and ripple effects of soil erosion.
- When students have completed their charts, provide time for groups
to share their work. A sample completed Decision
Wheel has been provided as a guide for discussion.
The Quality of Our Nation's Water
The EPA provides extensive information on the sources of pollution affecting
our nation's rivers and streams.
and Farming Practices in an Agricultural Watershed
Farming Practices Affect Water Quality?
National Water Quality Assessment
Studies by the U.S.
Geological Survey on Sources, Transport, and Fate of Agricultural Chemicals
Iowa: 30 Years
of Simulated Soil Erosion
erosion: An Agricultural Production Challenge