EQ: How do humans add to the erosion process?

EQ: How do humans EQ: How do humans add to the erosion add to the erosion

process?process?

How do humans add to the How do humans add to the erosion process ?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 ErosionHuman 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

LoggingLogging• People use trees to build

homes, make furniture and paper.

• In a method called clear-cutting, 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.

MiningMining• 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.

FarmingFarming• 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.”

ConstructionConstruction• 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 CheckQuick Check

• What is MAINLY responsible for preventing erosion?

A. mining

B. farming

C. rooting of plants

D. logging

Quick CheckQuick Check

• Which human activity is related to logging?

A. strip mining

B. clear-cutting

C. drought

D. open-pit mining

Quick CheckQuick Check

• A landslide is an example of

A. erosion

B. a mining process

C. A logging process

D. A farming process

Quick CheckQuick Check

In what part of the United States was the “Dust Bowl” located?

• A. northern

• B. eastern

• C. western

• D. central

Quick CheckQuick Check

What was the MAIN cause of the “Dust Bowl”?

A. floods

B. Storms

C. wind

D. drought