What are surface prcesses that work to break down rock called?
How do chemical and mechanical weatherng differ?
MECHANICAL - occurs when rocks are broken by physical processes.
CHEMICAL - happens when chemical reactions dissolve minerals.
Why is ICE WEDGING most obvious in the mountains?
Because the temperature changes in the mountains allow for the repeated freezing & thawing of water caught in the cracks of rocks.
When water mixes with CARBON DIOXIDE in the air, what forms?
How is SURFACE area related to CHEMICAL weathering?
Increased surface area allows for more interactions of rocks with water & oxygen!
How does climate affect CHEMICAL & MECHANICAL WEATHERING?
CHEMICAL - occurs more rapidly in warn, wet climates
MECHANICAL - occurs more in cold climates
Why is a soil's composition dependent on weathering?
Because it contributes sediment to the soil
What is soil a mixture of?
Weathered rock & water
Decayed organic matter & oxygen
What is it called when decayed organic material turns into a dark colored material?
What is each layer of a soil profile called?
In which horizon of a soil profile is LITTER usually found?
Which horizon of a soil profile does LEACHING normally occur?
Which horizon of a soil profile is the PARENT MATERIAL usually found?
How can rock type within the parent rock affect the type of vegetation that grows there?
Different rocks provide different nutrients for plant growth.
Where is erosion most common?
How does soil erosion affect topsoil?
It washes it away.
What are human activities that contribute to soil erosion?
Why is SOIL EROSION more COMMON in areas that lack adequate vegetation?
Because plant roots help keep the soil in place.
How does GRAZING affect soil?
It can improve soil quality due to organic matter that livestock leave behind.
Grazing can be used in place of plowing in no-till farming.
Overgrazing can leave soil vulnerable to wind and water erosion.
How does AGRICULTURAL CULTIVATION contribute to soil erosion?
Farmers who plow their land uproot plant roots which hold the soil in place.
Why does clearing tropical rain forests have an ADVERSE effect on soil quality?
The soil is only good for farmers for a FEW YEARS before the nutrients are gone because the soil is almost infertile below the first few centimeters.
How do farmers attempt to manage crops to reduce soil erosion?
Plant shelter belts to protect crops from wind erosion
Use animals to graze over vegetation instead of plowing.
Practice no-till farming
What is a method in which level-topped areas are built into steep-sided hills?
How do construction sites attempt to reduce erosion?
Cover exposed ground with plastic
Spray exposed soil with water
Replace topsoil that has been removed during construction
What happens to mountains from weathering over long periods of time?
Become rolling hills
Can small animals mechanically weather rocks?
Yes, when they burrow by breaking apart sediment.
What damage can tree roots do?
Grow into cracks and break rock apart.
How do caves form?
When slightly acidic groundwater dissolves limestone.
How is LIMONITE formed?
By iron-containing minerals that weather to form the rustlike material.
Do different typs of rock weather at different rates?
YES, In humid climates - marble statues weather rapidly
Granite statues weather more slowly
What are 5 factors that affect soil?
Slope of land
Types of rock
Types of vegetation
Amount of time rock has been weathering
What does LEACHING do?
Removes the material from the UPPER layer of soil.
What type of soil is Oklahoma predominately?
Does the slope of the land affect soil development?
Thin, poorly developed soils form on STEEP slopes.
Valleys often have THICK, WELL-DEVELOPED soils.
What happens from erosion from exposed streams?
It can cause streams to fill with excessive amounts of sediment.
What are the benefits of contour farming?
(On gentle slopes, planting along the natural contours of the land.)
It slows the flow of water down the slope and helps prevent the formation of gullies.
What is a method used to prevent erosion on steep slopes?
Terracing (the reduce runoff by creating flat areas and shorter sections of slope.)
What is NO-TILL FARMING?
Farmers leave plant stalks in he field over the winter. At the next planting, they seed crops without destroying these stalks or plowing. This provides cover for the soil year-round that reduces water runoff and soil erosion!