Section 1
____________ weathering is a physical process that breaks rock into fragments
mechanical
The middle layer of soil is called the ____ horizon
B
TRUE/FALSE Soil erosion is a good thing for plants
FALSE
mixture of weathered rock, decayed organic matter, minerals, water, and air
soil
Which river runs through the Grand Canyon?
Colorado
_________weathering is a process when chemical reactions dissolve minerals in rocks
chemical
Above bedrock is the ___ horizon
C
Forest _______ is the removal of trees and plants in an area
harvesting
Decayed organic matter that turns into a dark-colored material...it is a very healthy top-soil
humus
Which explorer (and what year) was the first to travel down the entire length of the Colorado River and Grand Canyon?
John Powell in 1869
The process of ___________ is when water enters cracks and freezes...expands and breaks down rock.
ice wedging
In the very top layer of soil, a fertile layer of soil called _______ is found
humus
Farmers can manage crops by planting ______ belts to protect it from wind erosion.
shelter
Terracing or terrace farming
TRUE
a chemical process that occurs when iron is exposed to oxygen
oxidation
O
With ___ ____ farming, plant stalks are left behind by farmers with the new crop being planted in between rows.
no-till
weathering
What was the name of the theory proposed by John Douglas that helps explain what cut out the Grand Canyon roughly 5.5 million years ago?
Spill-over theory
TRUE/FALSE Pictured Rocks is a place that has both chemical and mechanical weathering taking place
TRUE
Which of the following IS NOT one of the 5 factors that affect soil formation?
climate --- slope of land --- altitude of land --- type of rock ---- type of vegetation ----- time soil has been weathered
altitude of land
_________ farming is when farmers cut into the sides of hills allowing them to plant crops on flatter areas.
Terrace
oxidation
Lake Bidahochi