EQ: How do humans
add to the erosion
process?
How do humans add to the
erosion process ?
1. What are natural and
non natural ( human)
agents of erosion ?
2. How can logging and
mining lead to
erosion?
3. How can farming lead
to erosion
4. How can construction
lead to erosion ?
Human Activity and Erosion
Natural agents of erosion:
– Wind
– Moving water
– Gravity (landslides)
– Waves
– Glaciers (rivers of ice)
Humans add to the
erosion process:
– Logging
– Mining
– Farming
– Construction
Logging
• People use trees to build
homes, make furniture and
paper.
• In a method called clearcutting, all the trees in an
area are cut down.
• Roots that used to hold the
soil in place die and decay.
• Rain washes the soil away.
• Soil has been robbed of
nutrients and minerals
needed for plants to grow.
Mining
• To get minerals from the
ground, miners strip away
the surface of the land.
• Strip-mining and open-pit
mining remove plants from
an area.
• Plants prevent soil erosion
by flowing waters and wind.
• Without plants, erosion
speeds up.
• Thousands of years may
pass before enough topsoil
builds up to support plant life.
Farming
• Planting crops can benefit many
people.
• Planting crops and an
unexpected natural event can
produce a disaster.
• From 1930 to 1937, a drought
struck the mid-western part of
the U.S.
• Grasses could have protected
the soil during the drought.
• Winds picked up the topsoil and
blew it 100s of miles eastward.
• This event is known as the
“Dust Bowl.”
Construction
• Building of roads,
buildings, and
communities removes
natural barriers, such
as plants, to erosion.
• Erosion speeds up
and the land becomes
barren and ugly.
• Today, city officials
consider erosion
when they plan new
construction plans.
Quick Check
• What is MAINLY responsible for
preventing erosion?
A.
B.
C.
D.
mining
farming
rooting of plants
logging
Quick Check
• Which human activity is related to logging?
A.
B.
C.
D.
strip mining
clear-cutting
drought
open-pit mining
Quick Check
• A landslide is an example of
A.
B.
C.
D.
erosion
a mining process
A logging process
A farming process
Quick Check
In what part of the United States was the
“Dust Bowl” located?
•
•
•
•
A.
B.
C.
D.
northern
eastern
western
central
Quick Check
What was the MAIN cause of the “Dust
Bowl”?
A. floods
B. Storms
C. wind
D. drought