SS 120 LEC - Midterm - Study guide + Quizzes

Plant support is one function of soils. State four (4) ways soils support plants

(1)Nutrient supply, (2) Water supply, (3) Anchor for roots, (4) Air supply/ventilation for root respiration, (5) Protection from toxins, (6) Temperature moderation/regulation

Climate regulation is another function of soils. State two (2) ways soils regulate the earth's climate

(1) Albedo or reflectivity effect, (2) Thermal properties including thermal conductivity and specific heat capacity, (3) Evaporation flux, (4) Carbon cycling

List four (4) other functions of a soil

(1) Water filtration, (2) Flood risk mitigation, (3) Engineering or construction medium, (4) Water filtration or water quality regulation, (5) Antibiotics research, (6) Carbon sequestration

How do macronutrients differ from micronutrients?

Macronutrients are consumed in larger quantities ; micronutrients are consumed only in smaller or trace amounts by plants.

Name the four (4) major macronutrients and state their sources

C - From the Atmosphere (Air), H - From water, O - From Air and Water, N - From the Atmosphere and Organic matter

On what basis are soil parent materials classified?(like definition)

Mode of transport to point of soil formation

Residuum

(parent material) Developed from underlying bedrock (no transport)

Colluvium

(parent material) Transported by gravity, e.g., landslides or other mass movement

Alluvium

(parent material) Transported by stream, rivers, creeks

two main climate factors that control soil formation

Temperature & Precipitation (Rain, Snow)

three properties of slope that control soil formation

Angle, Position, Aspect

%slope =

tan(angle in degrees)×100 =

the four soil forming processes

Additions, Losses (subtractions), Transformations, & Translocations

Which soil horizon in a profile is called the zone of eluviation and why?

E-Leaching loss or washing out or depletion of organic matter or minerals

horizon sub-designation "k"

(horizon sub-designation) Carbonate accumulation

horizon sub-designation "k" master horizon it's associated with

(horizon sub-designation within) B

horizon sub-designation "t"

(horizon sub-designation) Clay accumulation

horizon sub-designation "t" master horizon it's associated with

(horizon sub-designation within) B

horizon sub-designation "p"

(horizon sub-designation) Effects of plowing (ploughing)

horizon sub-designation "p" master horizon it's associated with

(horizon sub-designation within) A

horizon sub-designation "r"

(horizon sub-designation) Parent material from bedrock

horizon sub-designation "r" master horizon it's associated with

(horizon sub-designation within) C

The 3 main Rock types in the Rock Cycle

Igneous, Sedimentary, and Metamorphic

Igneous (in regards to rock cycle)

(in rock cycle) when a rock goes through Melting and Crystallization it becomes

Sedimentary (in regards to rock cycle)

(in rock cycle) when a rock goes through Weathering and Lithification it becomes

Metamorphic (in regards to rock cycle)

(in rock cycle) when a rock goes through Metamorphism

What the rock cycle looks like

Igneous, Sedimentary, and Metamorphic with arrows going from each one to the other, even back on itself. Those arrows labelled with the way it becomes each rock type.

The two textural classes of igneous rock

Extrusive(/Volcanic) and Intrusive

Extrusive

(Igneous textural class) fine textured - crystals too small to be visible

Intrusive

(Igneous textural class) From magma; coarse textured - large crystal grains

the two compositional classes of igneous rocks

Felsic(Slicic) and Mafic

Felsic

(Igneous compositional class) from high silica environment, or dominated by feldspars & Quartz

Mafic

(Igneous compositional class) from low silica environment; high is Magnesium & Iron or other heavy metals

the two processes that lead to lithification of sediment to form sedimentary rocks

Densification (or compaction or consolidation), and Cementation - or binding, gluing, welting of sediment

The three factors that drive the formation of metamorphic rocks

Heat; Pressure; Fluid, or circulation of fluids (water)

the four (4) most abundant elements in the earth's crust, in order of abundance

O2, Si, Al, Fe

the five (5) defining characteristics of a mineral

(1) Natural, (2) Inorganic, (3) Crystalline, (4) Solid, (5) Definite chemical composition

the basic building block of silicate minerals

Silica Tetrahedron / Silicon Tetrahedral / SiO4 ^4-

the three types of reactions in which Silica Tetrahedron is involved in the formation of silicate minerals

(1) Ionic bonding with metal cations, (2) Covalent bonding involving sharing of oxygen with other tetrahedra (polymerization), (3) Isomorphic substitutions

the five (5) common silicate structures based on Silica Tetrahedron

(1) Independent or Isolated tetrahedra, (2) Single-chain silicates, (3) Double-chain silicates, (4) Sheet silicates, (5) Framework silicates

types of non-silicate minerals

Oxides; Carbonates; Sulphates; Sulfides; Phosphates

Soil texture

Relative proportion, by mass, of mineral fractions (i.e., %-by mass of sand, silt and clay)

Munsell color designation set up

H V/C (Hue Value/Chroma)

Which of the three Munsell color components is most affected by addition of water?

Value

the four components of Earth System

Geosphere, Hydrosphere, Atmosphere, and Biosphere

Geosphere

(Earth System Component) Solid earth

Hydrosphere

(Earth System Component) Water

Atmosphere

(Earth System Component) Air - Gases

Biosphere

(Earth System Component) Plants, animals, microbes, etc.

The main phases of soil

mineral matter(45%), organic matter(5%), water(25%), and Air(25%)

Proportions of the main phases of soil

mineral matter(45%), organic matter(5%), water(25%), and Air(25%)

why the soil atmosphere has different composition from atmosphere

soil has More CO₂, less O₂ due to root/microbial respiration and limited air exchange

Soil functions (7 total, try for 4/5)

(1)Medium for plant growth, (2)Water quality regulation, (3)Carbon storage, (4)Climate regulation, (5)Habitat for organisms, (6)Engineering medium, (7)Flood risk mitigation

9 Macronutrients (w/ correct form they're taken up by plants)

C(CO2), H(H20), O(O2, H2O), N(NH4 ^+ ; NO3 ^-), Ca^2+, Mg^2+, K^+, P(H2PO4 ^-, HPO4 ^2-), and S(SO4 ^2-)

5 Micronutrients (w/ correct form they're taken up by plants)

Cu^2+, Fe^2+, Mn^2+, Ni^2+, Zn^2+, B(H3BO3, H4BO4 ^-)

Nutrients that come from Air and Water

(where derived from) C H O N

Nutrients that come from Soil Minerals

(where derived from) Ca, Mg, K, P, S, Cu, Fe, Mn, Ni, Zn, and B

How to determine what essential nutrients a mineral can provide given the chemical formula

any element that's a nutrient EXCEPT C, H, O, and N

Master Horizon Layers in order

O, A, E, B, C, R

O Horizon

(Master Horizon Abbrev.) Organic Layer

A Horizon

(Master Horizon Abbrev.) Topsoil

E Horizon

(Master Horizon Abbrev.) Eluviation Zone

B Horizon

(Master Horizon Abbrev.) Subsoil

C Horizon

(Master Horizon Abbrev.) Parent Material

R Horizon

(Master Horizon Abbrev.) Bedrock

O Horizon Characteristics

(Master Horizon Layer) Made of decomposed plants and animals. Found at the surface, dark in color.

A Horizon Characteristics

(Master Horizon Layer) A mix of soil and organic matter. Rich in nutrients, supports plant growth.

E Horizon Characteristics

(Master Horizon Layer) Light-colored, where minerals and nutrients are washed out (leaching).

B Horizon Characteristics

(Master Horizon Layer) Accumulation of minerals like clay and iron. Found below the A and E layers.

C Horizon Characteristics

(Master Horizon Layer) Made of unweathered rock or loose material, from which soil forms.

R Horizon Characteristics

(Master Horizon Layer) Solid bedrock beneath the soil profile.

pH

measure of how acidic or basic a substance is

pH ranges

Acid <7, Basic(/alkaline) >7, Neutral =7

Acid

pH<7

Basic/alkaline

pH>7

Neutral

pH = 7

Math for determining pH

given H+ in moles → - log(H+ mole number) = pH number

To find the hydrogen ion concentration [H+] from pH

[H+] = 10^−pH

Causes of Acidity

When carbon dioxide (CO₂) dissolves in water, it forms carbonic acid (H₂CO₃), which dissociates to release hydrogen ions (H⁺). (CO₂ + H₂O)

Causes of Alkalinity

Calcium carbonate (CaCO₃) is basic. When it dissolves in water, it releases hydroxide ions (OH⁻), which increase the pH, making the solution alkaline. CaCO3​→Ca^2+ + CO3^2−

Types of Weathering

physical, chemical, biological

Physical weathering Primary agents

(type of weathering) Freeze-thaw, root pressure. (Temp and Pressure)

Chemical Weathering Primary agents

(type of weathering) Hydrolysis, oxidation

Biological Weathering Primary agents

(type of weathering) Lichen, microbes

Igneous

(Class of rock) cooled magma

Sedimentary

(Class of rock) compacted sediments

Metamorphic

(Class of rock) heat/pressure-altered

Intrusive

(Igneous texture) coarse (slow cooling)

Extrusive

(igneous texture) fine (fast cooling)

Mafic

(Igneous Composition) dark, Mg/Fe-rich

Felsic

(Igneous Composition) light, Si/Al-rich

Top 4 most abundant elements in earth's crust

O, Si, Al, Fe

5 Non-silicates

Oxides, Carbonates, Sulfates, Halides, Phosphates

Example of Oxides

Hematite, Magnetite

Example of Carbonates

Calcite, Dolomite

Example of Sulfates

Gypsum

Example of Halides

Halite, Fluorite

Example of Phosphates

Apatite

5 soil forming factors

(Cl ORPT)Climate, Organisms, Relief (topography), Parent material, Time

4 soil forming processes

Additions, Losses, Transformation, Translocation