Chapter 16

The eluviation in this Alfisol is most evident at a depth of ______ feet.

1

In the diagram below, horizonation has begun in which image?

3

In the figure below, the zone of accumulation occurs where?

3

In the diagram below, eluviation has begun to create a distinct horizon in which image?

4

The primary source of nutrients for plants is found in the ___ horizon.

A

Which of the following is not true about the spatial scales at which soil scientists study soils?

A pedon must be significantly different in properties from the pedons adjacent to it.

This agriculturally productive soil is a(n)

Alfisol.

Which of the following is not a component of soil?

All are components of soil

What is a major difference between Inceptisols and Entisols?

All of these are major differences between Inceptisols and Entisols.

Which of the following is not true of soil?

All of these choices are correct

What type of organisms live in soil?

All of these choices are correct.

Extremely fertile soils that have been formed out of volcanic material are

Andisols.

What type of climate was this soil formed in?

Arid

The calcium carbonate in the B horizon indicates this is a(n)

Aridisol

In the diagram below, regolith forms in which area

B

In the map below, the pedogenic regime known as laterization would most likely be a factor at

B

Podzolization is most likely to occur in the ___ horizon.

B

The thick __ horizon in the soil profile shown in the diagram below is one of the distinguishing features of the _______ soil type.

B; Ultisol

What horizon is most prevalent in this Inceptisol?

C

Which of the following soils would probably have the lowest permeability?

Clay-rich soil being used as cattle pasture

In the map below, the pedogenic regime known as podzolization would most likely be a factor at

D

How might soil be used to either cover up or solve a crime?

Each soil has distinct characteristics that can be traced back to it place of origin

Which of the following types of soil is least strongly influenced by its climate?

Entisol

Which of the following soil types is most likely to be found in mountainous or sandy regions?

Entisols

The most common soil type on Earth is

Entisols.

This soil, which is frozen most of the time, is a(n)

Gelisol

Which of the following types of soil is most strongly influenced by its climate?

Gelisol

Areas that experience frequent water budget surpluses are most likely to experience which of these pedogenic regimes?

Gleization

Soils that were covered by continental ice sheets and have not developed since the last glacial advance are classified as

Histosols.

The material in this soil is glacially-derived colluvium. What soil order does it belong to?

Inceptisols

Which of the following is not a function that humus and other organic matter serve in making a soil healthy?

Increasing evaporation rates

What does the deep red color in this soil profile suggest?

Iron-bearing minerals have been leached downward

Which of the following is not true about the C horizon?

It accumulates iron, aluminum, clay, and other materials leached down from layers above it.

Which of the following is not true of soil texture?

It can be modified substantially by humans

Why are there no well-defined horizons in this soil profile?

It is usually frozen

The B layer in this soil is loess. What soil order does it belong to?

Mollisol

Which of the following is not a common cation that acts as a nutrient for plants?

Nitrogen

Which nutrient is most directly responsible for efficient water uptake and conservation?

Potassium

Which of these features is typical of soils in temperate environments?

Retention of nutrients within the crop root zone

Which of the following is not a function that organic matter serves in soil?

Separates soil particles

The bleached, grayish E horizon shown in the diagram here is characteristic of

Spodosols.

In the soil profile below, iron is present in both the top and bottom layer, as labeled, but why is only the second layer a reddish color?

The iron oxide was leached from the top layer in what was most likely a wet environment.

Which of the following is true of Mollisols?

They are found in places with seasonal moisture deficits.

This soil from the southeastern United States is a(n)

Ultisol

In the world map below, the purple color represents

Ultisols.

The soil pictured below is

Vertisols.

The diagram below is most likely from

a temperate environment because of the well-developed horizons.

agriculturally unproductive because the high concentration of cations in them causes them to leach away nutrients with positive ions

abundant organic matter and alkaline conditions.

Acidic soils tend to be

agriculturally unproductive because the high concentration of cations in them causes them to leach away nutrients with positive ions

Soils that have a blocky structure

are usually difficult to plow.

In general, warm, wet climates allow for fast formation of soils primarily because

chemical weathering proceeds at rapid rates.

Clay soils will usually have a higher cation exchange capacity than sandy soils because

clay particles have elongated surfaces that support negative charges

This soil profile is in an area where

conditions are neither too wet nor too dry.

In the world map below, the color that represents the soil type with the most ideal balance between leaching and retention of nutrients is

dark green.

The climatic features that tend to be most important in forming Aridisols include

descending air and high pressure.

Soils with shale-derived parent material usually differ from those from sandstone-derived parent material in that they tend to

form clays with more soluble cations than the sandstone-derived soils.

Vertisols, Aridisols, Oxisols, and Ultisols all have in common that they

form in warm climates.

The pore space, or porosity, of soils composed mainly of clays is generally

greater than that in soils composed mainly of sands because the grains in clays do not fit together very well compared to sands.

Soils that are most likely to be compacted have

high porosity.

Hygroscopic water

is generally unavailable to plants because its high surface tension causes it to adhere so tightly to the soil particles

The ideal texture for a soil to minimize the risk of pollution is one that

is of moderate sized particles, to reduce ponding while still having some filtering capabilities.

The soil shown in the photograph below has a reddish tint, which may mean that

it has abundant aluminum and/or iron oxides.

The soil shown in the photograph below has a greenish or grayish tint, which may mean that

it has been waterlogged at some point.

In which colored area in the world map below has slash and burn agriculture been most prominent in leaving relatively infertile soils beneath the forest exposed?

light blue

A forensic application of soil science might involve

linking the soil type on a shoe to the soil type where a crime took place.

If a soil is too sandy, it will usually

lose its water and nutrients too easily.

Typically when a glacier recedes, the deposited material leaves behind

material of a wide range of sizes, until streams moving around the area begin to sort the material by size.

In general, compared with soils on gentle slopes, soils on steep slopes will tend to be

more easily eroded.

Compared with Mollisols, Alfisols tend to be somewhat

more likely to become acidic.

The primary difference between the O and A horizons is that the O horizon usually has

more plant litter than the A horizon.

The most direct impact of the process of capillary action is to

move water to the surface.

soil erosion due to wind is a major problem.

overgrazing leads to the loss of vegetation.

Gelisols generally are most closely associated with

permafrost.

In the world map below, the color that represents soils that are least mature is

pink

All of the following are in the topsoil layer and contribute directly to processes occurring there except

plant litter.

The limited horizonation in the soil type pictured below occurs because

precipitation is limited.

In the world map below the color that represents soils that swell and shrink excessively is

purple

Compared with soils beneath built-up areas, soils beneath a forested watershed will generally

reduce surface runoff.

overgrazing leads to the loss of vegetation.

reducing rainsplash.

The use of strip cropping helps to control soil erosion by

reducing runoff.

The wind erosion processes shown at A and B in the diagram below are

saltation and creep

Soils composed mostly of primary minerals will tend to have a higher percentage of _____ and a lower percentage of _____ than soils composed mostly of secondary minerals.

sand; clay

In the diagram below, the yellow area represents

secondary silicate minerals.

In terms of particle sizes, secondary minerals are usually

smaller than primary minerals because they have undergone fairly intense chemical weathering processes compared to primary minerals.

The red areas in the map below are places where

soil erosion due to wind is a major problem.

The absence of a layered structure in the soil pictured below occurs because

swelling as the soil absorbs water and shrinking as it dries out removes the horizonation.

A major danger of soils that become too acidic is that

the harmful effects of heavy metal pollutants become magnified.

In general, the healthiest soil texture for plants is one in which

there is a relatively even percentage of sand, silt, and clay.

Liquefaction will generally be most problematic in

waterlogged, earthquake-prone locations.

Loess is transported by _____ and is important because _______.

wind around glaciers; it is fertile