Science of Life Explorations
Erosion and Soil Quality:
Prevent Erosion
We know that soil is important to us. Healthy
soil provides us with healthy plants.
Soil is part of the ECOSYSTEM because so
much depends on it.
Soil is also part of the WATER CYCLE!
It filters water as it soaks down to the
groundwater.
Geologists and ENGINEERS study soil to decide the
best way to use it and protect it.
Sometimes soils and bedrock are mined and used in
manufacturing. Homes and other buildings as well as
streets and highways are built on top of soil.
When soil is used incorrectly or not cared for, it can
be blown away by winds, or washed away by water.
EROSION happens naturally, but our actions can make
it worse.
Soils and water are linked to one another in the
ecosystem. What happens to one affects the
other. When soil is eroded, it often ends up in
the water system.
In this lesson we’ll talk about soil erosion and
water quality.
What do you know about erosion and water quality?
What is erosion?
How does erosion occur?
Can we prevent erosion?
What is a watershed?
How does the water cycle work?
What is water quality?
How can we protect soils?
How can we protect water quality?
What is erosion?
Erosion is the movement of soil particles from one place to another by
wind, water or other actions.
If we don’t care for and protect our soils, we lose soil that took a very
long time to form. We can’t go out and make more soil when we need it.
Soil must be protected.
Erosion occurs naturally. We can’t stop it. But we can limit it. In many
cases, soil erosion can be very serious because we have not protected the
soils.
Erosion affects our water. We will learn about the WATER CYCLE and
WATERSHEDS. Controlling erosion is one way to protect our water
quality! Can you think of more ways?
How does erosion occur?
Erosion is almost always caused by wind and water.
Wind can blow across large, open fields and take just a bit of soil away. We
usually don’t see it. If the wind is strong enough, and the soil is dry, we may
see dust blowing by.
Water is a major cause of
erosion. Name the very
large, famous canyon which
was formed by erosion.
____________________
Water can actually wear
away rock! So it is easy to
see how water can move
soil, too.
Name a large United States
river that has been moving
soil and changing the land for
hundreds of years.
_____________________
Clue: Look on a U.S. map for
the city of New Orleans,
which is at the ‘mouth’ of
this very important river.
Don’t run off on us now!
Rain is needed by plants and usually moves into soil. If soil is too dry and
‘crusty’,rain may run off. If soil is too wet, or SATURATED, rain water also
runs off the surface. We call this water RUNOFF.
Creeks, streams and rivers can change course over years as they move small
amounts of soil. During heavy downpours, rain moves quickly toward streams,
carrying loose soil. When creeks, rivers and streams run high or flood, they
move large amounts of soil and can even wash away their banks.
This satellite photo of the Mississippi River DELTA shows how soil moves along
a river and is deposited at its mouth. Would you agree that a river can move
large amounts of soil?
(thanks to: www.earthkam.ucsd.edu/public/images/pdf/Mississippi_River_
Delta.pdf) Go online for other satellite photos of the earth!
One other form of erosion happened in New York state a very long time
ago. GLACIERS are huge sheets of ice and snow which move across the
land very slowly. Glaciers are so thick and heavy, they can carve soil and
rock. As they melt, their streams of water continue the process.
The Finger Lakes of New York
were carved by a glacier!
Can we prevent erosion?
No, but we can limit it.
By using the land wisely, we
can limit our affect on the
environment.
GlobExplorerTM
When people change the shape and use of land,
they affect the way water moves through the soil.
One example is using a bulldozer to prepare for
building a house or creating a new road. Soil
without any plants on it is SUSCEPTIBLE to
movement by wind and water. Farmland that has
not yet been planted may also suffer erosion on
windy or rainy days.
Later we will talk about watersheds.
You will see how water, in the form of
rain or streams, always moves toward
GROUNDWATER or larger bodies of water.
Moving water picks up and carries particles
of soil and other small things we can’t see.
Some may not be good for us.
How does erosion affect us?
Trees and plants hold soil in place and also take
up water out of the soil for their use. These
two photographs show clearing of land and
cutting down trees. Using what you have read,
answer this question on a separate sheet of
paper:
“Can clearing trees and changing
the land cause erosion?”
Remember to:
1. Restate the question
2. Answer the question
3. Give reasons that support your answer
4. Write your conclusion
What is a watershed?
A watershed is a land area where all the water drains into a the same body of
water. It can be large or small. It is affected by hills and valleys.
For instance the Mississippi River watershed is very large. Look on a map or
globe and try to figure out its size.
Try this website: http://www.nps.gov/miss/features/factoids/
41% of the
continental United
States are in the
Mississippi River
Watershed!
Color the watershed
area light blue.
Erosion is the movement of soil by two main forces,
_______________ and _______________.
A watershed is an area where all the rain flows toward one body of water.
____yes
____no
Circle the true statement:
a. We can stop erosion
b. We can reduce erosion
The Mississippi River’s watershed is very large. Water from 31 states flow into it. How many states are not part of that watershed? ________
Trees, and shrubs can reduce erosion
___ by slowing wind
___ by slowing movement of rain water
___ by keeping soil in place
___ by all of these actions
Name two things creeks and streams can carry to larger bodies of water:
____________________________________________________
Vocabulary:
Accumulation - the act of gathering into one large amount
Absorb - to soak in
Algae - simple plants that live in water
Aquatic - having to do with water
Atmosphere - the ‘air’, a general term for the air around us from the ground up to what we call ‘space’
Condensation - part of the water cycle, one of the ‘states’ of water when it becomes liquid after being in a gas form
Cover crops - crops grown in a field to add nutrients and hold soil in place
Debris - usually loose pieces of things (such as wood, plastic) that have become scattered and moved by wind or water
Delta - an area at the mouth (the end) of a river where it deposits soil and sediments as it flows into a larger body of water
Ecosystem - a ‘community’ where all parts of the environment are working together
Engineers - people trained to design and build things
Erosion - a natural process where wind and water slowly break things down
Evaporation - the process of water changing from liquid to a gas
Glacier - a huge sheet of ice covering land and moving slowly over it
Nitrogen - a needed element found in soil and air, used by plants and people
Phosphorus -a needed element found in soil and used by plants and people
Precipitation - the various forms of water (rain, snow and sleet) that drop from the atmosphere
Vocabulary continued:
Riparian buffer - a strip of plants growing along a water body to slow erosion and the movement of fertilizers and chemicals into that water (riparian means something to do with a river)
Runoff - an overflow of rain (or water from a stream) not able to soak into soil which then moves across the soil surface instead
Saturated - when something like soil or cloth or a sponge is full of water and can’t take in anymore
Subsurface - below the surface
Susceptible - something that is likely to be affected by something else (for example, when you are not eating well, you are susceptible
Transpiration - transpiration is done by plants and trees to release moisture into the air (remember that plants taken in water which is needed when they make their own ‘food’)
Vapor - the gas, not liquid, form of water
Water cycle - the whole cycle of water from precipitation to ground or surface water to evaporation and condensation
Waterbody - any large body of water like a stream, pond or ocean
Watershed - the area of land where all the rain and groundwater eventually makes it way into one particular body of water
Windbreak - trees, shrubs or even buildings or fences that are placed to reduce the speed of wind blowing across an area
In these lessons, students will learn about erosion of soil and how it affects water quality.
Students will be told that erosion happens naturally and can’t be stopped, but that our
actions can affect it and make it worse. Students will learn that all the water that comes
as rain or snow is part of a watershed for a particular body of water. Students will see
illustrations of the water cycle and how it works in a watershed.
Students will be told that erosion and the effectiveness of the water cycle contribute to
water quality. Students will be made aware that not only soil, but unwanted debris as well
as fertilizers, pesticides, oils and gasoline can be moved by water into the water system.
Students will learn that there are ways to protect soils from erosion and protect our water
systems.
What is erosion?
Pg 1 Erosion is a very natural thing. It has been happening since the earth was formed.
Erosion can occur slowly or quickly. Soil is an important natural resource which shouldn’t
be taken for granted. It can be lost or destroyed many times faster than it is created.
Soil health is linked to water quality. Pg 2 What do you know about erosion?
In a group setting, discuss these questions with students. Some children will have some
knowledge about erosion and the water cycle. By the end of these activities, students
should have a better understanding.
Pg 3 Erosion - Is it a bad thing?
Erosion is something we should try to limit, but we can’t stop it. And should we try?
There are many beautiful aspects of our earth that are a result of erosion. Shifting
dunes along the ocean, or in the arid deserts, as well as curving rivers, deep valleys and
sculpted rock formations are formed by wind and water.
Pg. 4 Water moves earth. Ask students about their memories of heavy rains and
flooding. Ask how many have tossed leaves or sticks into a fast moving flow of water
down their street after a storm? How many are aware of the power of water to move
heavy objects?
The satellite photo was taken by NASA astronauts. It is a great illustration of the
power of water. From space, we see the delta and the underwater deposits of soil and
sediments moved by the Mississippi River. In a few pages, we will talk about the vast
part of the country included in the Mississippi River Watershed.
Erosion caused by ice and snow is not something we think of today, yet a majority
of New York State was once covered by a glacier. If you have access to a molded
topographical map of the state, it is a great tool for this lesson. For an extension
activity, students can research glaciers and explain in writing or to the class what a
drumlin is or, how the melting ice and subsequent water flow has as much to do with
erosion as the ice did.
An important take away thought on this lesson is that erosion can’t be stopped, but our
activities, such as bulldozing, can contribute to erosion.
How does erosion affect us? It may not seem that erosion has much to do with our daily
lives. This is where it ties in to water quality, which is important to everyone. Unless we
see damage first hand after a heavy rainstorm, we may never relate how erosion from
water moves soil. This page offers two activities. First, students are directed to do a
writing assignment discussing man-made causes of erosion. You may direct the length
of the writing assignment as you desire. Secondly, we discuss watersheds. Perhaps you
have signs in your area that tell you what watershed system you live in. Remind students
that no matter where they live, ALL WATER moves toward a larger body of water.
The Dust Bowl is the name given to a time in United States History.
Much of the midwest was prairie. This is a type of flat land with special grasses
growing on it. Grasses have deep roots and hold soil in place. The soil was
healthy and rich. It seemed to be great for farming!
However in the 1920s and 30s, much of the prairie grasses had been removed so
farmers could grow crops on the rich soil. For many years, rainfall was limited,
causing a drought. With no grasses and only a few crops, winds began to blow soil
away. Much of the land suffered erosion. These photos were taken in Oklahoma
in 1935. Everything was covered with dust. Dust storms lasted for days. Many
people moved west for a better life. A large section of the country was called
‘The Dust Bowl”.
For Teachers and Parents:
name____________________________
Student Lesson: Erosion and Water Quality
1. Erosion is the movement of soil by two main forces,
water
wind
_______________
and _______________.
2. A watershed is an area where all the rain flows toward one body of water.
____yes
____no
X
3. Circle the true statement:
a. We can stop erosion
b. We can reduce erosion
4. The Mississippi River’s watershed is very large. Water from 31 states flow
50-31=19
into it. How many states are not part of that watershed? ________
5. Trees, and shrubs can reduce erosion:
___ by slowing wind
___ by slowing movement of rain water
___ by keeping soil in place
X by all of these actions
___
6. Name two things creeks and streams can carry to larger bodies of water:
soil,
fertilizer, debris, pesticides, chemicals, oil, gasoline, etc
____________________________________________________
7. Evaporation is part of the water cycle. It means:
___ water goes back up into the atmosphere (air)
___ water runs down hills into streams
8. Is water quality the same throughout the world?
____yes
____no
9. Silt in the water is good for fish
____yes
____no
10. Oil and gasoline from cars can runoff driveways into our water systems.
____yes
____no
11. I can draw an example of the water system.
____yes
____no
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