Deck 12: Soils

Question 1

Three-quarters of the soil's metabolic activity is generated by ________.

A) earthworms
B) trees
C) mammals
D) microorganisms
E) humans

Answer 1

D

Question 2

Which is NOT a main soil-forming factors?

A) climatic
B) geologic
C) topographic
D) chronological
E) human activity

Answer 2

E

Question 3

Which of the following NOT a reason earthworms increase the fertility of the soils in which they reside?

A) Formation of aggregate soil particles
B) Mixing of leaf litter
C) Increased nitrification
D) Increase of soil nutrients
E) Stimulation by plowing for agriculture

Answer 3

E

Question 4

Dead plant parts are known as ________ when they accumulate on the surface of the soil.

A) humus
B) organic debris
C) microorganisms
D) nutrients
E) litter

Question 5

Humus has a consistency not unlike that of ________.

A) putty
B) sponges
C) gelatin
D) rock
E) roast beef

Question 6

The weathered layer of loose inorganic material overlaying unfragmented rock below is ________.

A) separates
B) regolith
C) clay
D) peds
E) horizons

Question 7

Most soil development takes place ________.

A) within seconds
B) within hours
C) within days
D) within years
E) on scales of time longer than human life spans

Question 8

The soil-forming factor which is said to make soil more than "just dirt" is the ________ factor.

A) climatic
B) biological
C) topographic
D) geologic
E) chronological

Question 9

In terms of topography, the deepest soils are ________.

A) on flat land
B) on the sides of hills
C) where erosion is fastest
D) on steep hills with sandstone bedrock
E) on random locations on the landscape

Question 10

The processes that deepen and age soils include all but the following:

A) translocation
B) addition
C) transformation
D) loss
E) taxonomy

Question 11

Earthworms ________.

A) literally "suck" nitrogen out of the soil
B) are not able to eat microorganisms
C) usually guarantee the soil will be poorly productive
D) are at their most numerous in arid climates
E) increase soil porosity

Question 12

The following is not an important soil microorganism:

A) fungi
B) bacteria
C) algae
D) protozoan
E) earthworm

Question 13

The true soil layer is known as ________.

A) loam
B) an oxisol
C) the solum
D) the interstices
E) the regolith

Question 14

Earthworms ________.

A) are underneath almost all Earth's unfrozen last surface
B) excrete casts
C) are also known as bacteria
D) usually deplete soil fertility
E) have many more species than insects

Question 15

Globally, the influence of this soil-forming factor fades with time.

A) geologic
B) biological
C) chemical
D) climatic
E) topographic

Question 16

Parent material is closely associated with which soil-forming factor?

A) geologic
B) climatic
C) topographic
D) chronological
E) biological

Question 17

Soils are considered part of the ________.

A) lithosphere
B) hydrosphere
C) geosphere
D) atmosphere
E) biosphere

Question 18

Humus is associated with ________.

A) a light color
B) a low cation exchange capacity
C) a "hard" consistency
D) rotted and rotting plant and animal remains
E) a low soil fertility

Question 19

Which of the following is NOT considered part of the soil?

A) fine, fragmented mineral particles
B) water
C) air
D) dead and rotting plant parts
E) living plants

Question 20

Much soil material is actually wasted bits of rocks and composed of ________.

A) humus
B) loam
C) silica
D) hydrogen
E) air

Question 21

________ is a measure of the ease with which water moves through the soil.

A) Permeability
B) Porosity
C) The wilting point
D) The field capacity
E) The capillarity

Question 22

In terms of a typical soil-water balance in Most of the United States, which season is associated with a soil water surplus?

A) summer
B) spring
C) the one with the greatest evapotranspiration
D) the one which is warmest
E) the high sun season

Question 23

The size groups within the standard classification of soil particle sizes are termed ________.

A) epipedons
B) separates
C) cations
D) humus
E) pedons

Question 24

Which of the following is NOT true of soil air?

A) rich in carbon dioxide
B) poor in oxygen
C) nearly saturated
D) insignificant air movement
E) full of nutrients

Question 25

A major determinant of a soil's water holding capacity is its ________.

A) colloids
B) pH value
C) soil profile
D) structure
E) microorganisms

Question 26

Which of the following represents an addition to soil water?

A) percolation
B) evaporation
C) transpiration
D) weathering
E) none of the above

Question 27

The main "type" of water that plants use is ________.

A) vadose
B) artesian
C) hydroscopic
D) capillary
E) aquiclude

Question 28

The measure of a soil's capacity to hold water and air is called ________.

A) porosity
B) permeability
C) peds
D) its profile
E) foaminess

Question 29

________ is a soil texture in which none of the three main soil separates dominates the other two.

A) Adobe
B) Humus
C) Loess
D) Loam
E) Podzol

Question 30

________ is least available to plants because it is held in chemical combination with the minerals in the soil.

A) Free water
B) Capillary water
C) Combined water
D) Hygroscopic water
E) Gravitational water

Question 31

Air within the soil is usually highly saturated and rich in ________.

A) oxygen
B) argon
C) carbon dioxide
D) aluminum
E) none of the above

Question 32

The difference between field capacity and the wilting point is called ________.

A) soil moisture
B) available soil moisture
C) groundwater
D) runoff
E) capillary water

Question 33

This type of water is held to soil particles by adhesion and is normally unavailable to plants.

A) combined water
B) hygroscopic water
C) gravitational water
D) capillary water
E) meteoric water

Question 34

Organic matter usually comprises about ________ percent of total soil volume.

A) 5
B) 10
C) 25
D) 35
E) 95

Question 35

The dynamic relationship between precipitation and evaporation in any given location is the ________.

A) capillary action
B) leaching
C) illuviation
D) soil-water balance
E) hydrologic cycle

Question 36

Which of the following terms is usually confused with but is not directly descriptive of soil moisture?

A) wilting point
B) pore spaces
C) field capacity
D) groundwater
E) soil-water budget

Question 37

The smallest-sized pieces of a soil are ________.

A) sands
B) gravels
C) clays
D) silts
E) cobbles

Question 38

After gravitational water has drained away, ________ is the water that remains in the soil and is available for use by plants.

A) groundwater
B) hygroscopic water
C) capillary water
D) water of cohesion
E) free water

Question 39

The term "clay" is a reference to ________.

A) structure
B) loam
C) texture
D) chemistry
E) biota

Question 40

Gravitational water is ________.

A) a temporary form of soil moisture
B) the same thing as capillary water
C) present when the wilting point is reached
D) the same thing as hygroscopic water
E) the most important source of water for plants

Question 41

In the soil, which of the separates are associated with significant chemical activity in soil?

A) sand
B) silt
C) clay
D) aluminum
E) radium

Question 42

Which of the following is NOT a property of soil clay?

A) occurs as thin laminar sheets
B) made primarily of silt
C) colloidal in size
D) Many chemical reactions occur on its surfaces.
E) It is able to hold water to itself.

Question 43

The B horizon is usually called ________.

A) regolith
B) litter
C) colloids
D) topsoil
E) subsoil

Question 44

Which of the following horizons is found furthest from the surface of the soil?

A) O
B) R
C) B
D) C
E) E

Question 45

A soil with a large percentage of clay would be ________ and ________.

A) porous, permeable
B) non-porous, non-permeable
C) porous, non-permeable
D) non-porous, permeable
E) fertile, red in color

Question 46

On the standard pH scale, the number 10 indicates a ________ soil.

A) acid
B) neutral
C) basic
D) fine-textured
E) porous

Question 47

Like ________, humus is a catalyst for chemical reactions and a reservoir for plant nutrients and soil water.

A) clay
B) mud
C) silt
D) cations
E) iron

Question 48

The cation exchange capacity is most closely associated with ________.

A) sand
B) silt
C) color
D) regolith
E) colloids

Question 49

The laminar sheets which are clay particles are ________.

A) the largest particles in the soil
B) chemically inert
C) called cations
D) negatively charged
E) relatively rare compared to other soil materials

Question 50

For all soil orders, the surface layer is the ________.

A) epipedon
B) solum
C) bedrock
D) cation
E) hard pan

Question 51

Roughly one half of the volume of an "average" soil type is composed of ________.

A) organic material
B) clay
C) pore spaces
D) cations
E) rocky fragments

Question 52

Several soil horizons together make up a ________.

A) soil profile
B) ped
C) soil series
D) soil order
E) hardpan

Question 53

Soil structure is usually determined by clumps called ________.

A) colloids
B) peds
C) loam
D) solum
E) catenas

Question 54

Which pH reading is suitable for most plants and soil microorganisms?

A) 0
B) 3
C) 5
D) 7
E) 10

Question 55

Based on the pH scale soils are neutral at ________.

A) 7.0
B) 7.5
C) 8.0
D) 6.5
E) 6.0

Question 56

Among layers of the soil horizon, the one with the most organic material is ________.

A) O
B) A
C) B
D) C
E) R

Question 57

The minerals that form cations are known as ________.

A) anions
B) electrons
C) bases
D) clays
E) loams

Question 58

The unconsolidated parent materials beneath the level of roots is called the ________ horizon of soil.

A) O
B) A
C) B
D) C
E) bedrock

Question 59

A soil with a high cation exchange would likely be ________.

A) dark in color
B) very sandy
C) fertile
D) impermeable
E) thin

Question 60

________ brings soil materials from the A horizon to the B horizon.

A) Translocation
B) Loss
C) Addition
D) Transformation
E) Porosity

Question 61

In semiarid climates, grass roots transport much ________ from the B horizon to the A horizon.

A) gravel
B) clay
C) phosphorus
D) calcium
E) uranium

Question 62

A soil containing only an A horizon atop partially altered parent material is said to be ________.

A) solum
B) acidic
C) series
D) immature
E) phreatic

Question 63

The unconsolidated parent material beyond the reach of most roots is ________.

A) the A horizon
B) loam
C) the C horizon
D) solum
E) the F horizon

Question 64

Eluvial materials are deposited in the soil's ________ horizon.

A) O
B) B
C) A
D) R
E) E

Question 65

Mature tropical soils are generally noteworthy for their ________ color.

A) black
B) tan
C) red
D) white
E) gray

Question 66

The main value of the extensive terminology of the Soil Taxonomy is its ________.

A) lack of subdivisions
B) basis in the genesis of soils
C) acceptance in every country in the world
D) basis in observable characteristics
E) status as being the first soil classification

Question 67

The existence of a B horizon is an indication of a(n) ________ soil.

A) immature
B) colloidal
C) zonal
D) episodic
E) mature

Question 68

The shallowest soils can be found in which regions?

A) cold and wet
B) cold and dry
C) warm and wet
D) warm and dry
E) rainforests

Question 69

The pedogenic regime typified by silica removal and iron-aluminum concentration near the surface is ________.

A) laterization
B) podzolization
C) gleization
D) calcification
E) salinization

Question 70

The soil classification system currently in use in the United States is called the ________.

A) Great Soil Group
B) Soil Taxonomy
C) Latin System
D) Edaphic Index
E) Pedogenic Factor

Question 71

Which pedogenic regime is most closely associated with the drier prairies of North America?

A) gleization
B) salinization
C) laterization
D) calcification
E) podzolization

Question 72

The boreal forest in subarctic locations is the typical setting for ________.

A) erosion
B) gleization
C) calcification
D) podzolization
E) laterization

Question 73

The pedogenic regime associated with the tropical moist climates is ________.

A) podzolization
B) salinization
C) laterization
D) gleization
E) calcification

Question 74

The pedogenic regime associated with high annual precipitation and temperature is ________.

A) gleization
B) laterization
C) calcification
D) salinization
E) fixation

Question 75

Seeds germinate mainly in the ________ horizon.

A) A
B) B
C) C
D) E
E) R

Question 76

In the United States, the ________ states are most closely associated with gleization.

A) West Coast
B) Gulf Coast
C) East Coast
D) Rocky Mountain
E) Great Lakes

Question 77

The main pedogenic regimes do NOT include ________.

A) calcification
B) colloidization
C) podzolization
D) salinization
E) gleization

Question 78

A dense layer, often forming in the B horizon under calcification is ________.

A) solum
B) regolith
C) a hardpan
D) a latosol
E) vadose

Question 79

The "A" horizon or combined "O/A" horizons of the soil are known as the ________.

A) subsurface horizon(s)
B) illuviation layer(s)
C) epipedon
D) regolith
E) colloidal layer(s)

Question 80

Soils made up of mainly ________ do not develop a true soil structure.

A) peds
B) sand
C) loam
D) humus
E) silt