Section 2.2 Fundamental Components of Soil Flashcards
Fundamental Components of Soil
This is called a
A B C are called
SOIL PROFILE
Soil Horizons
Refer to “A3” of your Lecture Supplement for more information
Components of Soil include:
- – M
- – O
- – W
- – A
- – Minerals
- – Organic Matter
- – Water
- – Air
Non-living crystalline compounds found in rocks.
The main solid component of most soils Include:
- – Primary
- – S and
- – C M
What has the smallest amount in rocks?
Most?
- – Primary
- – Secondary and
- – Carbonate Minerals
organic material 5%
minerals 45%
(Water 25% Air 25%)
Primary Minerals
- Relatively unchanged since forming from ?
- What is a common primary mineral found in sand sized particles?
- What contributes to MOVEMENT of water and air through soils because of their larger size?
- but Primary Mnerals provide ___ fertility and water holding
- lava
- Quartz
- Primary Minerals
- poor
Secondary Minerals:
- Form from the weathering (?) of primary minerals
- What is the DOMINANTmineral among the fine (clay) soil particles?
- Secondary Minerals improve soil F and
- W holding
T/F:
Secondary Minerals are the breakdown particles of primary minerals
- breakdown
- SECONDARY MINERALS
- Fertility
- Water
T
?
Clay
The general relationship between
?
- High clay + low quartz and primary =
- equal parts=
- low clay + high quartz and other primary
The general relationship between
particle size and mineral composition
- High clay + low quartz and primary = clay
- (Lacustrine)
- equal parts = silt
- (Eolia)
- low clay + high quartz and other primary = gravel and sand
- (fluvial)
Carbonate Minerals
- What does Carbonite Minerals mainly consist of?
- Where do Carbonite Minerals originate from ?
- What do Carbonite Minerals maintain ???
- Very high carbonate levels may interfere with ? growth
- Carbonates can be detected with dilute ?(effervescence)
- calcite and dolomite
- limestone bedrock
- alkaline soil pH
- plant
- HCl
About Carbonite Minerals…
Mainly ? and ? which originate from limestone bedrock
Maintain a soil a pH
Very high ? levels may interfere with plant growth
Carbonates can be ? with dilute HCl (effervescence)
calcite and dolomite
alkaline
carbonate
detected
Carbonite
Organic Matter
- Plant, animal and ? residues
- “Active organic matter” is readily ?
- “H____” is resistant to decomposition
- microbial
- decomposed
- Humus
Organic Material
Plant, animal and microbial residues
“?AOM?” is readily decomposed
“Humus” is
Active organic matter
resistant to decomposition
Active and Resistant Organic Matter
Benefits of Organic Matter
– Breaks down to supply plant n________
– Enhances soil _____ by binding s____ p_____together
– Provides food source for M________
nutrients
structure ….. soil particles
Microbes
?
Organic Matter
Benefits of Organic Matter
- – Breaks down to supply plant nutrients
- – Enhances soil structure by binding soil particles together
- – Provides food source for microbes
Organic Matter
Benefits of Organic Matter
– Breaks down to s____ p____ n_______
– E_____ s_____ s_______ by binding soil particles together
– Provides f_____ s_____ for m_______
supply plant nutrients
Enhances soil structure
food source for microbes
Soil Water:
- Is the water held in pore spaces by the combined forces of adhesion and cohesion
- Adhesion is the attractive force between a w m and the s p s
- Cohesion is the attraction between two ____ ____
water molecules and the soil particle surface
water molecules
Soil Reservoir
The total water held in pore spaces against gravity is called “the s___ r_____”
soil reservoir
SOIL Water
- Is the water held in ? ?
- by the combined forces of adhesion and cohesion –
- ? is the attractive force between a water molecule and the soil particle surface
- Cohesion is the attraction between two water molecules
- The total water held in pore spaces against gravity is called ?
pore spaces
Adhesion
“the soil reservoir”
Soil Water is:
the water held in pore spaces by the combined forces of adhesion and cohesion
- Soil Water is…
- Adhesion is…
- Cohesion is…
- “the soil reservoir” is…
- the water held in pore spaces by the combined forces of adhesion and cohesion
- the attractive force between a water molecule and the soil particle surface
- the attraction between two water molecules
- The total water held in pore spaces against gravity
?
Sand-sized Soil Particles
Have relatively low total S A with which to retain water
Sandy soils provide P W H but good drainage
surface areas
poor water holding
Talk about pic
Sand-sized Soil Particles
Have relatively low total surface areas with which to retain water
Sandy soils provide poor water holding but good drainage
Clay Textured Soils
?
Clay Textured Soils
Clay Textured Soils:
- Clay soils have large total surface areas and retain ??
- Much of the water in clay textured soils may be held so tightly that it is U___________ for _____ _____ however.
more water
unavailable for plant use
Clay Textured Soils
Clay soils have large total surface areas and retain more ?
– Much of the water in clay textured soils may be held so tightly that it is ? for plant use however.
– Medium textured soils tend to have the best combination of…. whc for pg
water
unavailable
water holding characteristics for plant growth
Soil Air
Is not i so its composition varies from place to place
interconnected
What is not interconnected so its composition varies from place to placeplace to place?
SOIL AIR
What has…
- – relative humidity near 100%
- – a higher CO2 content than the atmosphere
- – reduced O2 content compared to atmosphere
SOIL AIR
- – Sandy soils replenish ___ ___ more rapidly than clay textured soils
- – ? soils reduce air flow and promote the buildup of toxic gases from anaerobic decomposition
- – Tillage of wet soils leads to compaction which reduces pore space and slows ? movement
soil air
Waterlogged
air
Soil Air
Is not interconnected so its _____ varies from place to place –
- Has relative humidity near %
- Has a higher CO2 content than the
- Has reduced ? content compared to atmosphere
- Sandy soils replenish soil air more rapidly than cts
- Waterlogged soils reduce air flow and promote the buildup of…TGfAD
- Tillage of wet soils leads to ? which reduces pore space and slows ??
composition
- 100%
- atmosphere
- O2
- CLAY TEXTURED SOILS
- toxic gases from anaerobic decomposition
- compaction … air movement
What is Soil?
- 3D natural body of u m on the surface of the earth
- subjected to, and influenced by pm c biotic i and t
- the genetic and environmental factors of and characteristics from the parent materials (pm or pgm) from which it was derived and is capable of supporting the growth of land plants.
unconsolidated matter
parent material, climate, biotic influences and topography
?
has been all acting over a period of time to produce a product that differs in
- p
- c
- b
- morphological and
- mineralogical properties
Soil
- physical,
- chemical,
- biological,
the
3D natural body of unconsolidated matter on the surface of the earth
is
the
definition
of
SOIL
What is a simple definition of Soil?
- Unconsolidated
- Occurs Naturally
- Has Distinct Layers
Simple definition of soil?
A cross section of soil showing A,B and C horizons is known as a “____ _____”
OCCURS NATURALLY unconsoludated, distinct layers,
“soil profile”
