Soils- Exam 1 (2- Soil Formation)

chemistry; cooling

2 things that affect the nature of the resulting igneous rock are the _____ of the magma, as well as the rate of _____.

new material input

4 Pedogenetic Processes: What are additions?

materials leave soil, never to return

4 Pedogenetic Processes: What are losses?

changes in materials

4 Pedogenetic Processes: What are transformations?

movement of materials

4 Pedogenetic Processes: What are translocations?

soil profile development; aeration and drainage; macropores

A negative result of burrowing animals is that the mixing of mineral soil material disrupts _____ _____ _____. A positive result of burrowing animals is that the burrows improve soil _____ and _____. The cavities that result from this burrowing are called _____.

regolith

All the loose particles above bedrock are called the _____.

floodplains, alluvial fans, and river deltas

Alluvial parent material is transported by flowing water, such as _____, _____ _____, and _____ _____.

2

An increase of 10°C = __X chemical reaction rates.

thin; < 5 cm

Are the O horizons in East Texas thick or thin? How thick/thin?

parent material

As rock weathers, its loose particles become _____ _____.

unstable; erosion

As slope degree increases, the soil on the slope becomes more _____, and more geologic _____ occurs.

conifers

Between conifers and broadleaf trees, which acidifies soil the most, usually?

chemical

Chemical weathering of rock results in _____ changes.

sand; silt

Coarse textured aeolian parent materials (also known as _____) create dunes. Fine textured aeolian parent materials (also known as _____) create loess.

dunes; loess

Coarse textured aeolian parent materials (also known as sand) create _____. Fine textured aeolian parent materials (also known as silt) create _____.

gravity; coarse

Colluvial parent material is transported by _____, and is usually _____ textured.

yes

Do resistant minerals, such as quartz sand, remain in the E horizon?

acidification

During _____, acid breaks down minerals.

dissolution

During _____, water dissolves minerals, forming a solution.

hydration

During _____, water joins with minerals, forming hydrated solids. Due to the hydrated solids, the rock is then more easily weathered.

hydrolysis

During _____, water reacts with minerals, and the minerals form solutions.

solutions

During hydrolysis, water reacts with minerals, and the minerals form _____.

few; weak; quickly; basalt

During the formation of igneous rock, if the magma cools quickly, _____ crystals develop, the rock will be _____ and will weather more _____. _____ is an example of a fast cooling igneous rock.

many; tough; slowly; granite

During the formation of igneous rock, if the magma cools slowly, _____ crystals develop, the rock will be _____ and will weather _____. _____ is an example of a slow cooling igneous rock.

Weches; 30 million

East Texas has experienced _____ Formation over the last ___ _____ years.

truncated

Eroded or scraped soils are called _____ soils.

acidify; lowered

Forest vegetation tends to _____ soil (pH is _____).

Pleistocene epoch; 12,000 to 2.5 million

Glacial parent material was developed during the _____ _____, _____ to ___ _____ years ago.

lower; base pumpers; cations

Grasses _____ acidity. Because they lower acidity, they're called _____ _____. As they lower acidity, they bring basic _____ to the surface, which is what causes the pH to rise.

Ap

If the A horizon has been previously plowed, it's called ___.

slate; marble

Igneous and sedimentary rock CAN become metamorphic. Shale becomes _____; limestone becomes _____.

magma

Igneous rocks come from _____.

volcanic ash

In 1980, Mt. St. Helens erupted, forming _____ _____.

highly; sapric

O Horizons: The Oa horizon is _____ decomposed and _____ in organic soils.

moderately; hemic

O Horizons: The Oe horizon is _____ decomposed and _____ in organic soils.

slightly; fibric

O Horizons: The Oi horizon is _____ decomposed and _____ in organic soils.

Oi; leaves, twigs, etc.

O Horizons: Which horizon, within the O horizon, has the most easily recognizable structures? What are these structures?

Oa

O Horizons: Which horizon, within the O horizon, is highly decomposed and sapric in organic soils?

Oe

O Horizons: Which horizon, within the O horizon, is moderately decomposed and hemic in organic soils?

Oi

O Horizons: Which horizon, within the O horizon, is slightly decomposed and fibric in organic soils?

Oa

O Horizons: Which horizon, within the O horizon, is the darkest colored and has no recognizable structures?

physical and chemical

Parent material has a great influence on resulting soil development, especially on the soil's _____ and _____ properties.

marine sediment

Parent material that was formerly the ocean floor and uplifted by water recedes is called _____ _____.

pedogenetic

Parent material, climate, biota, topography, and time. These are the 5 factors of soil development. Combined, these factors drive the 4 _____ processes.

degree of decomposition

Peats are classified by their _____ of _____.

fibric; hemic; sapric

Peats are classified by their degree of decomposition. They can either be _____ (slightly decomposed), _____ (moderately decomposed), or _____ (highly decomposed).

slightly; moderately; highly

Peats are classified by their degree of decomposition. They can either be fibric (_____ decomposed), hemic (_____ decomposed), or sapric (_____ decomposed).

stress; fractures

Physical Weathering: Disintegration: Over time, heating and cooling cycles create _____, which creates _____.

wedge

Physical Weathering: Disintegration: Water within a crack can freeze and expand, acting as a _____.

secondary

Primary minerals dissolve, forming _____ minerals.

R

Rock layers beneath the regolith are called __ layers.

metamorphic

Rock that has changed form due to heat and pressure is _____ rock.

calcium rich marine sediments

Sedimentary Rocks: Limestone is composed of _____ _____ _____ _____.

sand

Sedimentary Rocks: Sandstone is composed of _____ sized particles.

clay

Sedimentary Rocks: Shale is composed of _____ sized particles.

landscape and mode of deposition

The 3 types of parent material are residual, colluvial, and alluvial parent material. They are classified as to which type according to _____ and _____ of _____.

mineral; high; top; input; mixing; earthworms and fine roots; organic matter

The A horizon is dominantly _____ with _____ organic matter. The A horizon is at the _____ of the mineral profile. The A horizon's degree of development depends on the amount organic matter _____ and the amount of _____. To have a good A horizon, _____ and _____ _____ are key. The A horizon has high biological activity due to the presence of _____ _____.

what has been illuviated

The B horizon has many different subordinate designations, depending on......

humus

The Bh horizon is rich in _____

aluminum and iron sesquioxides and is also rich in humus

The Bhs horizon contains......

aluminum and iron sesquioxides

The Bs horizon contains......

significant clay accumulation

The Bt horizon contains......

> 20

The O horizon is dominantly composed of organic matter (__ ___% by weight).

plant communities; chemistry

The amount of organic matter in wetlands depends on _____ _____ and wetland _____.

aspect; slope

The term that describes the direction in which a slope faces is _____. The term that describes the degree of steepness is _____.

steep; north; south

The term that describes the direction in which a slope faces is aspect. Aspect is especially important in _____ terrain. In the Northern Hemisphere, cooler, more moist habitats are found on the _____ side of mountains; warmer, drier habitats are found on the _____ side of mountains.

very little

Today, roughly 30 years after Mt. St. Helens erupted, how mush soil has developed?

homogenous; heterogeneous

Transition Horizons Examples: EB (more like E than B), and BE (more like B than E) are both fairly _____. E/B and B/E are both _____.

false

True or False? All master horizons are present in each soil profile.

true

True or False? C horizon is not part of the soil because there are no signs of pedogenetic processes.

true

True or False? Due to the lack of organic matter present, the E horizon has much lower biological activity.

igneous, sedimentary, and metamorphic

What are the 3 basic types of rocks?

residual, colluvial, and alluvial

What are the 3 types of parent material?

disintegration, abrasion, and plants/animals

What are the 3 types of physical weathering of rocks?

translocations, transformations, additions, and losses

What are the 4 pedogenetic processes?

parent material, climate, biota, topography, and time

What are the 5 factors of soil formation?

hydrolysis, hydration, dissolution, acidification, and oxidation

What are the 5 types of chemical weathering of rocks?

Bt, Bs, Bh, and Bhs

What are the different subordinate designations of the B horizon?

leaching

What is another name for eluviation?

accumulation

What is another name for illuviation?

Soil Genesis

What is another name for the 4 pedogenetic processes, collectively?

physical and chemical weathering are working together at the same time

What is happening, basically, during rock weathering processes?

peat

What's another name for organic parent material?

sedimentary

When loose particles become consolidated into rock, _____ rock is formed.

oxygen; slower; organic matter

When wetlands are saturated, they have low _____ levels, which results in _____ decomposition, which causes _____ _____ to accumulate.

B

Which horizon is called subsoil?

E

Which horizon is known as the zone of eluviation?

B

Which horizon is known as the zone of illuviation?

A and E

Which horizons are called surface soil?

O, A, and some of E

Which horizons may incorporate plowing?

aeolian

Which type of parent material is deposited by wind?

organic

Which type of parent material is formed when plant growth exceeds decay?

large; fine

Within floodplains, water is sorting particles. High energy water → _____ particles fall out of suspension; low energy water → _____ particles fall out of suspension.

B

You can split horizons (A, E1, E2, B1, B2, B3, C). There are usually multiple __ horizons.

roots; burrowing animals

_____ can act as wedges, and _____ _____ also physically weather rock.

oxidation; iron

_____ is another name for rust, which especially affects _____.

residual

_____ parent material is formed in place (not transported), and is very rare or non-existent.

alluvial

_____ parent material is transported by flowing water.

colluvial

_____ parent material is transported by gravity, and is usually coarse textured.

glacial

_____ parent material was developed during the Pleistocene epoch, 12,000 to 2.5 million years ago.

water; slowly; rapidly

_____ plays a big role in soil development. In cool, dry climates, soil develops _____. In warm, moist climates, soil develops _____.