3.2 Earth's Soil Flashcards
soil
the loose surface material that covers most land
soil made of
a mixture of minerals, organic matter, living organisms, gases, and water
what is soil produced from
parent material
how is soil produced
weathering
weathering
the breakdown of rocks by physical chemical or biological processes
where do particles that are produced by weathering go
transported or deposited to land or sediment underwater
horizons
soil layers
how are soil horizons distinguished from one another
diff color texture mineral content and organic content
soil profile
vertical arrangement of horizons
soil profiles are used for what
to help distinguish soil types, and can also be used to predict soil fertility
how many diff soil horizons are there
O, A, B, and C
O horizon means
organic horizon
A horizon means
topsoil
B horizon means
subsoil
C horizon
layer of poorly weathered or unweathered rock which contains a high concentration of parent material
soil erosion
the removal of the fertile top layers of soil
what naturally erodes soil
wind and flowing water
what can slow erosion
plants bc the roots help anchor the top layers of soil
A horizon
the upper layer of soil in which plants have most of their roots
A horizon is made of lots of what
organic matter and microorganisms
what soil layers are the most nutrient rich
A and O horizons
the most nutrient rich soils are the ___ (most/least) productive
most
B horizon mostly made of what
minerals from weathered parent material
can B horizons make plant growth
not a lot
is the C horizon capable of plant growth
no its infertile
what can unnaturally erode soil
human activities such as deforestation agriculture and urbanization
in what way is soil an ecosystem service
they filter and clean water that goes through them so they help provide clean water for drinking
soil texture
a mixture of differently sized particles caused by erosion
sand
largest + heaviest particles of soil that is gritty
silt
powdery particle of soil that is medium size and weight
clay
smallest particle of soil that you cant even see with naked eye that is smooth
how many different types of soil particles are there and what are they
3 – sand silt clay
soil texture triangle
triangle that is helpful for farmers bc it shows all the types of soil and it helps them determine what types of soil they can use to plant their plants by giving percentage of different particles of soil
how do you determine what soil you have from a soil triangle
given the percentages of diff particles go up or down based on the arrow to wtv adds up to that number to make 100 and do that for all 3 and whenever that intersects its the soil type
if something is permeable does it increase or decrease erosion
decrease
what soil horizon has the highest concentration of organic matter
o
