Weathering I
Soil Horizons
Weathering II
Soil Composition
Soil Formation
100
What type of climate causes chemical weathering to occur fast?
hot, wet climates
100
This soil horizon is also known as topsoil.
'A' Horizon
100
The agent of weathering in which sand carried by wind hits the side of a cliff, reshaping it over time.
Abrasion
100

Soil containing lots of clay will hold (MORE, LESS, THE SAME) water than soil containing lots of gravel. 

more

100
In order for the process of soil formation to occur, bedrock must be ________________ to weathering and erosion.
exposed
200
What two factors affect the rate of weathering?
Rock type and climate
200
This fertile soil contains equal parts of sand, silt, clay, water, and air, making it the best type of soil for growing plants.
Loam
200
Moles, gophers, prairie dogs, and some insects loosen and break apart rocks in this agent of weathering
Animal action
200
These slippery, slimy friends help decompose dead organic matter. They also do most of the work of mixing humus into soil.
WORMS
200
Humus is made of __________
decayed organic material
300
In what way do plants cause chemical weathering?
When acids from their roots seep into rocks.
300

This soil horizon is the last one to form, although it is located in the middle of two other horizons. What is this horizon?

'B' horizon; forms last because it's a mixture of 'A' horizon and 'C' horizon (minerals and clay seep down from the 'A' horizon)

300
Tree roots grow between cracks in rocks and break them apart in what type of weathering?
Mechanical weathering
300
Soil that contains lots of humus is fertile. What does this mean?
It is rich in nutrients and plants grow well in it.
300
Subsoil is not fertile because it contains very little _____
Humus
400

Describe the climate where Granite lasts a long time when it is used for building.

the climate is mostly cool and dry.

400
In which soil horizon would humus be found?
Topsoil or 'A' horizon
400

What does the B horizon consist of?

clay, minerals, & little humus

400
In what way do burrowing animals enrich the soil?
Their waste adds nutrients; when they die, their remains add nutrients to the soil; they mix air into the soil when they burrow; they mix humus into the soil.
400
A mixture of rocks, minerals, decayed organic material (dead stuff), air, and water is called __________
soil
500
How are weathering and erosion different?
Weathering breaks rock into smaller pieces. Erosion carries the pieces away.
500

This inorganic material is the BASIC material that makes up soil. Without it, soil wouldn't form.

bedrock. Exposed bedrock weathers into smaller pieces until it is part of the soil.

500
Explain why chemical weathering occurs faster in hot, wet climates than i cool, dry climates.
A lot of rainfall provides water needed for chemical reactions to occur. Hot temperatures cause chemical reactions to occur faster.
500

How do plants depend on soil to survive? 

Plants live and grow in soil. 

500
Humans could not survive on Earth without soil. Explain why this is true.
Humans are part of the food chain so we are animals that get our food from plants that live in soil and from animals that eat the plants that live in soil.
M
e
n
u