Deck 17: Soils and Environment

Question 1

Which soil horizon is known as the zone of accumulation?

A)A horizon
B)B horizon
C)C horizon
D)R horizon

Answer 1

B

Question 2

Soil scientists and engineers view soil in essentially the same way.

Answer 2

False

Question 3

The A horizon of a soil is typically richer in organic matter than is the B horizon.

Answer 3

True

Question 4

The unified soil classification system, which is based on soil texture, is particularly useful for agricultural purposes.

Question 5

Why was Times Beach, Missouri, evacuated in 1983?

A)Soils had eroded so deeply in a large rainstorm that streets were irreparably damaged.
B)Soils had become contaminated with dioxin.
C)Soils had become infertile because of excessive agricultural use.
D)Expansive soils damaged most of the buildings in town.

Question 6

Soil cohesion is enhanced by the presence of

A)gravel and sand particles
B)clay and silt particles
C)subsurface water
D)organic matter

Question 7

A sharp peak in sediment yield in the Piedmont region around 1960 corresponded with a period of

A)conversion of land to agriculture
B)extensive off-road vehicle use
C)heavy rainfall
D)rapid urbanization

Question 8

How do soils become fertile?

A)deep and thorough leaching of parent material to release nutrients
B)mild weathering of parent material and addition of organic matter
C)human manipulation to retain moisture and improve texture
D)intimate interaction with the soil biota

Question 9

Shrink-swell potential of a soil is dependent upon

A)the hydraulic conductivity of the soil
B)the proportion of clay in the soil
C)the proportion of fine sand in the soil
D)the chemistry and water content of the soil

Question 10

Soil fertility depends primarily on bedrock type.

Question 11

Clay soils tend to resist deformation because clays have high cohesion and high intra-grain friction.

Question 12

In what ways are soil surveys useful for land-use planning?

A)They provide the basis for rating limitations for specific land uses.
B)They provide maps showing the shrink-swell potential of soils.
C)They provide the basis for determining land valuation.
D)They show where existing soils have been covered by urbanization.

Question 13

What is hydraulic conductivity?

A)the velocity at which water passes through soil
B)the proportion of sand and gravel in a soil
C)the number and sizes of pore spaces in a soil
D)the ability of a porous material to transmit water

Question 14

The principal advantage of the Universal Soil Loss Equation is

A)ease of use and ability to evaluate the potential impact of conservation practices
B)rapid estimation of soil erosion at every location in a site of interest
C)ready estimation of reservoir siltation
D)prediction of the amount of nutrient loading in a stream adjacent a farm field

Question 15

Weathered material that remains in its place of formation is called

A)residual soil
B)transported soil
C)expansive soil
D)horizontal soil

Question 16

In what way is color an indicator of soil drainage?

A)Well-drained soils tend to be well aerated and red in color.
B)Poorly drained soils tend to be well oxidized and red in color.
C)Moderately drained soils tend to be green in color.
D)Colors of soils are more reflective of organic matter than of drainage.

Question 17

Off-road vehicle use contributes to soil problems by

A)loosening soil and changing the hydrology of a site
B)polluting soil with vehicle emissions
C)changing the local rainfall characteristics
D)changing the classification of a soil

Question 18

How do engineers define soil?

A)solid Earth material that has been altered by physical, chemical, and biological processes
B)solid Earth material strong enough to support structures
C)solid Earth material that can be removed without blasting
D)solid Earth material that is generally fertile

Question 19

Urbanization influences soil erosion processes primarily because of

A)increased runoff from impermeable surfaces
B)increased soil pollution from street runoff
C)vegetation removal and soil disturbance at construction sites
D)desiccation of soils through draining and pumping of water

Question 20

Soil taxonomy is a classification system based on

A)the processes that formed different soils
B)physical and chemical properties of the soil profile
C)divisions and subdivisions of soil texture
D)the organic matter content of the B horizon

Question 21

Expansive soils typically present minor, localized problems.

Question 22

Off-road vehicles typically reduce soil erosion by compacting the soil.

Question 23

A soil E horizon is an eroded horizon.

Question 24

Coarse-grained soils tend to have relatively low compressibility, low cohesion, low erodibility, and high hydraulic conductivity.

Question 25

________ is the ability of a soil to resist deformation.

Question 26

Agricultural soil erosion affects the amount, but not the fertility, of the soil.

Question 27

A soil that consists of nearly equal amounts of sand and silt with a lesser amount of clay is called a(n) ________.

Question 28

An argillic B horizon is enriched in ________ transported from the A horizon.

Question 29

An argillic soil horizon is enriched in clay moved from the A horizon.

Question 30

Soil strength is primarily a function of cohesion, friction, and vegetation.

Question 31

Soil ________ refers to the ease with which soil particles can be moved by wind or water.

Question 32

________ are aggregates of soil particles that comprise soil structure.

Question 33

Soils with the highest hydraulic conductivity consist of ________.

Question 34

Response to vibrations is one aspect of soil ________.

Question 35

________ works with the natural topography to reduce soil erosion.

Question 36

________ is the physical and chemical breakdown of rocks.

Question 37

________ is the ability of soil particles to stick together.

Question 38

The ________ horizon of a soil is a zone of intense leaching.

Question 39

Impact of urbanization on soil erosion is primarily a problem during the construction phase.

Question 40

Soil erosion is primarily a major problem only at the site where it occurs.

Question 41

A soil ________ is a series of soils arranged by age according to their relative profile development.

Question 42

A(n) ________ soil profile has a well-developed B horizon.