Weathering and Soil Flashcards
What is weathering?
the break up of rock due to exposure to process at or near the earth’s surface
What are the two types of weathering?
mechanicAL and chemical
How do mechanical and chemical weathering differ?
mechanical-breaks without any change in composition
Chemical-minerals are changed into new mineral
What are the 4 ways that mechanical weathering occurs?
Ice and water-frost wedging
Abrasion-the wearing away of rock material by grinding action
Plants and animals- roots and claws digging
upward expansion- exfoliation
What are the 3 ways that chemical weathering occurs?
water- hydrolysis
oxygen-oxidation
acid-acid rain
What kind of soil formed in the place where it was found. It matches the bedrock underneath it
Residual
What soil was moved to a new area by erosion. it does not match the bedrock beneath it
transported
What is a soil profile?
a cross section of the soil from the surface down
In what order to the horizons form?
D
C
B
A
What is the A Horizion?
Top soil
Gray to black
Contains humus-decaying organisms
What is the B Horizon?
Subsoil
Red brown
clay and other minerals leach (wash) down from above
What is the C Horizon?
Partly weathered bredrock
What is D Bedrock?
Parent material
What factors determine how fast weathering will occur?
Surface area
composition
climate
What three factors determine how fast weathering will occur?
Surface area
composition
climate
What three factors determine the composition of soil?
Climate
plants and animals
parent material
What forms in areas of little or no rainfall, generally sandy
desert soil
What kind of soil forms in areas with enough rain to support grass; fertile for farming
grassland
What type of soil forms in very wet, warm regions. Soil profiles are deep
tropical
What type of soil forms in cold climates. Slow weathering results in shallow profiles
arctic
What type of soil forms in areas with enough rainfall to support heavy tree growth
forest
What is found in Sterling areas?
Clay
For farms to be productive they must practice what to reduce soil erosion?
crop rotation
Planting trees along the edge of a field to reduce wind erosion creates a what?
windbreak
What is when farmers plow their fields perpendicular to the slope?
contour farming
Flattening a slop into ________ is used in cultivating rice
terraces
When farmers plant 2 different crops in one field to cover up bare soil, it is called _________
strip cropping
When all plowing, fertilizing, planting, and weeding is done at one time, a farmer is practicing the ________ method
no till
