The Ground Beneath Our Feet

S6E5. Students will investigate the scientific view of how the earth’s surface is formed.

h. Describe soil as consisting of weathered rocks and decomposed organic material.

i. Explain the effects of human activity on the erosion of the earth’s surface.

j. Describe methods for conserving natural resources such as water, soil, and air.

Directions

•Read each slide. Some slides are just facts,

look for the bold and underlined words to complete the notes

Precious Soil

You step on it. You stomp on it. You walk all over it. Soil doesn’t seem very precious. But it is. Without soil, which is a mixture of weathered rock and humus, there would be no plants. Without plants, we would have no food to eat and no oxygen to breathe. Soil is very precious to our way of living. Some people spend their entire careers studying soil.

•Why don’t you give it a try?

Explain this quote after you complete the notes

“The nation that destroys

its soil, destroys itself.”

What Is Soil Made Of?What Is Soil Made Of?Start hereStart here

Read this: Soil begins to form when bedrock is broken apart into small pieces of minerals (rock). The agents rain, ice, wind, freezing, and thawing can do this breaking. Chemical changes can do this , too to rock.

continue reading: Plants and animals that live in small rock pieces help break apart rocks. As plant roots grow down, they pry apart rocks. Burrowing animals, such as earthworms and ants, create tunnels between rock pieces. Some of these tunnels fill with air and water. Water expands as it freezes, further breaking apart the rocks.

Read: How Soil FormsRead: How Soil Forms

Humus becomes mixed with the rock pieces. Finally, a material that can be called soil is produced. Soil is a mixture of tiny rock particles, minerals, humus, water, and air. Soil takes a long time to form. It may take hundreds to thousands of years for one inch of soil to form.

Bacteria and fungi also help create soil. They decompose dead plants and animals for energy. The leftover plant and animal matter is called humus.

Food for thought: Explain this cartoon!

The importance of soil• Soil provides minerals and other

nutrients for plants.

• All animals get their energy from plants, either by eating plants or by eating animals that have eaten plants.

• Soil stores water for plant use

• Soil also prevents water run off

Uses of soil: How do Humans (people) use the land (soil)?

• Agriculture

• Development-Construction of homes, stores, office buildings, etc.

• Mining-Removal of iron, copper, and coal

Harm to Soil: Damage and loss

•Soil can be damaged from overuse by poor farming techniques or by over grazing.

•Deforestation: Cutting large masses of trees leaving bare forest land

•Overuse– soil loses its nutrients•Overgrazing– animals eat (destroy) plants

and leave the soil bare and exposed to erosion.

DEFORESTATIONclear cutting the trees

DEFORESTATIONclear cutting the trees

WHAT ABOUT THE ANIMALS? Where and how will they live?

pasture

pasture

Over grazing

Over grazing leads to ???

Overgrazing

SOIL POLLUTION chemicals being carried in water from field to river

Soil Movement: Erosion• Erosion is the process by which wind,

water or gravity transport soil and sediment from one location to another.

• Plant roots anchor the soil and keep it in place

• By taking care of the plants you also take care of the soil.

EROSION

DUST BOWL wind erosionWhen you are finished with this slide share go to: ikeepbookmarks.com (Alleyne), Geosphere, the soil food diner select any Dust bowl link to help you answer the questions watch the video clips, look at the images and use the links.

How do we SAVE OUR SOIL!

• Predict three ways that soil can be conserved?

Soil Conservation• Soil conservation is a method

to maintain the fertility of the soil by protecting the soil from erosion and nutrient loss

• Soil is a resource that must be conserved.

Methods of soil conservation

• 1. Contour plowing

• 2. Terracing

• 3. No till farming (non tillage)

• 4. Cover Crop

• 5. Crop rotation

Contour plowing• To prevent erosion farmers

plow and plant across the hill instead of plowing and planting down the hill.

• The rows act as

a series of dams

that slow the flow

of water

Contour planting

Terracing• If hills are very steep farmers

use terracing. Terracing changes the hill into a series of smaller flatter fields to reduce water runoff

Terracing

Terracing

No till Farming• Farmers leave old stalks in a

field to protect the soil. It prevents rain water run off and slows erosion. The decaying stalks renew the nutrients to the soil.

Non tillage

No till cotton plants

Cover cropCrops planted between the harvested

crop to replace the nutrients in the soil and prevent erosion

Cover crop

Crop rotation• Planting different crops in

rotation on the same piece of soil. Not planting the same crop year after year on the same ground. The rotation of crops slows the loss of nutrients

from the soil.Corn

Soy beans

Crop rotation

Plowing under cover crop to renew nutrients

LANDSCAPING FOR SOIL CONSERVATION (terracing)

Consider this!

Now go and select any Dust bowl link to help you answer the questions watch the video clips, look at the images and use the links.