Show:
MECHANICAL WEATHERING
SOIL PROFILE
ANIMALS IN THE SOIL
CHEMICAL WEATHERING
TERMS AND OTHER FACTS
100
answers will vary
What is an example of animal action mechanical weathering?
100
Horizon O.....bits of leaves and other organic material. it is on the surface
What is the name of the first horizon and what would you find there?
100
to decompose organic material
What is the role of bacteria?
100
oxidation...oxygen plus water
What is rust on a statue from?
200
falling rocks due to release of pressure
What is an avalanche and what is its cause?
200
subsoil.....clay and mineral deposits. only very long root systems
What is horizon B called and what would you find there?
200
mixes soil and creates pockets for air and water
What does the burrowing of animals do for soil?
200
combination of water and either sulfur, carbon, or nitrogen due to pollution, mainly
What is acid rain?
200
fertility is the ability to grow plants. more humus increases this. texture is the size of grains
What do the terms fertility and texture mean?
300
when water creeps into a crack in a rock, freezes, and causes the rock to split and crack further
What is frost wedging?
300
humus....organic material, plant roots. called topsoil
What is in layer A? what is it called?
300
answers will vary
Name 4 organisms/animals you could find in soil.
300
releases a weak acid that breaks the rock down
How does moss on a rock create a weathering effect?
300
physical weathering disintegrates or breaks down the rock chemical weathering decomposes or changes the mineral composition of the rock
What is the difference between physical and chemical weathering?
400
ex.: roots breaking apart a driveway. (answers can vary)
What is an example of mechanical weathering by plants?
400
broken pieces of rock are found. no organic material or roots
What is found AND not found in horizon C?
400
humus
When animals die and decompose they help form __________.
400
combination of carbon dioxide and rock...a weak acid that can weather rock
What is carbonic acid?
400
type of rock: some minerals break down or dissolve easier than others so can affect rate climate; hotter and more wet climates will increase the rate
Explain how climate and the type of rock influences the rate of weathering.
500
particles of rock are blown against other rock and wear it down.
What is abrasion?
500
horizon R or the bedrock. first because this is what soil originates from and is first laid down
What is the first horizon to form? why?
500
ex. digging a garden mixes the soil and allows for air and water to enter
What is a role humans play in soil development?
500
it breaks down rocks and begins the formation of soil
Weathering in nature is a good thing because........
500
porosity is the ability to absorb water. the type of material in the soil can affect porosity. for example, clay and sand can retain a lot of water permeability is the ability to allow water to flow through. the larger the grain (texture) increases permeablitiy
What are and what affects porosity and permeability?