Question 1

Hysteresis is the phenomenon whereby a soil has the same water content/potential relationship when it is being dried as when it is being wetted.

Accepted Answer

A) True 
 B)False

Question 2

The adsorption of water on soil surfaces encourages capillarity.

Accepted Answer

A) True 
 B)False

Question 3

Filling the bottom half of a flower pot with gravel will greatly improve the aeration of the soil-mix in the top half.

Accepted Answer

A) True 
 B)False

Question 4

The effect of soil organic matter on the amount of water available to plants is due to organic matter influence on total soil porosity as well as to the water-supplying power of the soil organic matter.

Accepted Answer

A) True 
 B)False

Question 5

In which of the following situations would you expect downward movement of soil water through the profile to be most rapid?

Accepted Answer

A) uniformly textured sandy loam profile 
B) sandy loam in upper layers with a clay band underneath 
C) sandy loam in upper layers with a layer of coarse gravel underneath 
D) clay texture throughout the profile 
E) silt loam in upper layers underlain by a sandy layer 
A) uniformly textured sandy loam profile 
B) sandy loam in upper layers with a clay band underneath 
C) sandy loam in upper layers with a layer of coarse gravel underneath 
D) clay texture throughout the profile 
E) silt loam in upper layers underlain by a sandy layer

Question 6

Which of the following best characterizes the field capacity of a soil?

Accepted Answer

A) maximum capacity of a soil to hold water 
B) water content of a soil with water potential of about -10 kPa 
C) the total capillary water in a soil 
D) a wetted soil prior to the removal of the gravitational water 
E) soil with water potential of -1500 kPa 
A) maximum capacity of a soil to hold water 
B) water content of a soil with water potential of about -10 kPa 
C) the total capillary water in a soil 
D) a wetted soil prior to the removal of the gravitational water 
E) soil with water potential of -1500 kPa

Question 7

The polarity of water helps account for the attraction of water molecules for each other.

Accepted Answer

A) True 
 B)False

Question 8

The matric potential of soil water is _____.

Accepted Answer

A) influenced greatly by the content of salts in the soil 
B) not influenced appreciably by the force of gravity 
C) is generally higher than that of pure water outside the soil 
D) is little affected by soil solids 
E) is lower in a sandy soil with 20 percent soil water than in a clay soil with same percentage of moisture 
A) influenced greatly by the content of salts in the soil 
B) not influenced appreciably by the force of gravity 
C) is generally higher than that of pure water outside the soil 
D) is little affected by soil solids 
E) is lower in a sandy soil with 20 percent soil water than in a clay soil with same percentage of moisture

Question 9

The tenacity with which water is held in soils is directly related to the soil moisture content;the higher the moisture level the greater the attraction of the water to the soil.

Accepted Answer

A) True 
 B)False

Question 10

At which of the following soil moisture potentials (expressed as kPa)is the waters' energy level lowest?

Accepted Answer

A) +5 
B) 0 
C) -31 
D) -1500 
E) -3100 
A) +5 
B) 0 
C) -31 
D) -1500 
E) -3100

Question 11

Plant roots obtain access to soil water in which of the following ways?

Accepted Answer

A) The roots contract and leave room in the pores for the water to move in. 
B) Roots extend into moist soil area. 
C) Water vapor moves from the wet soil areas to the root surfaces. 
D) Water flows to the roots by capillarity. 
E) both B and D 
A) The roots contract and leave room in the pores for the water to move in. 
B) Roots extend into moist soil area. 
C) Water vapor moves from the wet soil areas to the root surfaces. 
D) Water flows to the roots by capillarity. 
E) both B and D

Question 12

In which of the following "forms" of soil water are pesticides,excess plant nutrients and waste chemicals most apt to move through soils?

Accepted Answer

A) gravitational 
B) unsaturated 
C) available 
D) hygroscopic 
E) capillary 
A) gravitational 
B) unsaturated 
C) available 
D) hygroscopic 
E) capillary

Question 13

The osmotic potential would likely be lowest in soils of which of the following orders

Accepted Answer

A) Aridisols 
B) Histosols 
C) Oxisols 
D) Ultisols 
E) Spodosols 
A) Aridisols 
B) Histosols 
C) Oxisols 
D) Ultisols 
E) Spodosols

Question 14

The matric potential is due to the attraction of water molecules to soil solid surfaces.

Accepted Answer

A) True 
 B)False

Question 15

Which of the following statements concerning applications or capabilities of soil moisture measuring devices is (are)true for the tensiometer?

Accepted Answer

A) requires "destructive sampling" for each measurement 
B) good to turn on automatic irrigation at -50 kPa 
C) used to turn on irrigation when soil moisture potential reaches -200 kPa 
D) would give the same reading for both a loamy sand and a silt loam if both contained 15% moisture 
E) both A and D 
A) requires "destructive sampling" for each measurement 
B) good to turn on automatic irrigation at -50 kPa 
C) used to turn on irrigation when soil moisture potential reaches -200 kPa 
D) would give the same reading for both a loamy sand and a silt loam if both contained 15% moisture 
E) both A and D

Question 16

Which of the following expressions in kPa is most apt to characterize the gravitational potential of a clay loam surface soil?

Accepted Answer

A) -5 
B) -30 
C) 0 
D) +5 
E) -3100 
A) -5 
B) -30 
C) 0 
D) +5 
E) -3100

Question 17

The water content in a soil is known to be .2 m3/m3 and the potential of pure water outside the system is assumed to be 0.If the soil is a clay loam you would calculate the soil water potential (in kPa)to be

Accepted Answer

A) 0 
B) -5 
C) 20 
D) -20 
E) impossible to calculate with the data given 
A) 0 
B) -5 
C) 20 
D) -20 
E) impossible to calculate with the data given

Question 18

Unsaturated water flow _____________.

Accepted Answer

A) is faster than saturated flow 
B) is driven primarily by the force of gravity 
C) is stimulated by the osmotic potential 
D) is slower on sands than on clays if the soil moisture content is high 
E) occurs on soils that are at field capacity 
A) is faster than saturated flow 
B) is driven primarily by the force of gravity 
C) is stimulated by the osmotic potential 
D) is slower on sands than on clays if the soil moisture content is high 
E) occurs on soils that are at field capacity

Question 19

The osmotic potential is dependent upon the presence of salts and other solutes in the soil.

Accepted Answer

A) True 
 B)False

Hysteresis is the phenomenon whereby a soil has the same water content/potential relationship when it is being dried as when it is being wetted.

The adsorption of water on soil surfaces encourages capillarity.

Filling the bottom half of a flower pot with gravel will greatly improve the aeration of the soil-mix in the top half.

The effect of soil organic matter on the amount of water available to plants is due to organic matter influence on total soil porosity as well as to the water-supplying power of the soil organic matter.

In which of the following situations would you expect downward movement of soil water through the profile to be most rapid?

Which of the following best characterizes the field capacity of a soil?

The polarity of water helps account for the attraction of water molecules for each other.

The matric potential of soil water is _____.

The tenacity with which water is held in soils is directly related to the soil moisture content;the higher the moisture level the greater the attraction of the water to the soil.

At which of the following soil moisture potentials (expressed as kPa)is the waters' energy level lowest?

Plant roots obtain access to soil water in which of the following ways?

In which of the following "forms" of soil water are pesticides,excess plant nutrients and waste chemicals most apt to move through soils?

The osmotic potential would likely be lowest in soils of which of the following orders

The matric potential is due to the attraction of water molecules to soil solid surfaces.

Which of the following statements concerning applications or capabilities of soil moisture measuring devices is (are)true for the tensiometer?

Which of the following expressions in kPa is most apt to characterize the gravitational potential of a clay loam surface soil?

The water content in a soil is known to be .2 m³/m³ and the potential of pure water outside the system is assumed to be 0.If the soil is a clay loam you would calculate the soil water potential (in kPa)to be

Unsaturated water flow _____________.

The osmotic potential is dependent upon the presence of salts and other solutes in the soil.

The Soils Around Us

Formation of Soils From Parent Materials

Soil Classification

Soil Architecture and Physical Properties

Soil and the Hydrologic Cycle

Soil Aeration and Temperature

The Colloidal Fraction: Seat of Soil Chemical and Physical Activity

Soil Acidity

Soils of Dry Regionsalkalinity,salinity and Sodicity

Organisms and Ecology of the Soil

Soil Organic Matter

Nitrogen and Sulfur Economy of Soils

Soil Phosphorus and Potassium

Calcium,magnesium and Trace Elements

Practical Nutrient Management

Soil Erosion and Its Control

Soils and Chemical Pollution

Geographic Information About Soils

Prospects for Global Soil Quality As Affected by Human Activities

Filters

Exam 5: Soil Water: Characteristics and Behavior

Hysteresis is the phenomenon whereby a soil has the same water content/potential relationship when it is being dried as when it is being wetted.

The adsorption of water on soil surfaces encourages capillarity.

Filling the bottom half of a flower pot with gravel will greatly improve the aeration of the soil-mix in the top half.

The effect of soil organic matter on the amount of water available to plants is due to organic matter influence on total soil porosity as well as to the water-supplying power of the soil organic matter.

In which of the following situations would you expect downward movement of soil water through the profile to be most rapid?

Which of the following best characterizes the field capacity of a soil?

The polarity of water helps account for the attraction of water molecules for each other.

The matric potential of soil water is _____.

The tenacity with which water is held in soils is directly related to the soil moisture content;the higher the moisture level the greater the attraction of the water to the soil.

At which of the following soil moisture potentials (expressed as kPa)is the waters' energy level lowest?

Plant roots obtain access to soil water in which of the following ways?

In which of the following "forms" of soil water are pesticides,excess plant nutrients and waste chemicals most apt to move through soils?

The osmotic potential would likely be lowest in soils of which of the following orders

The matric potential is due to the attraction of water molecules to soil solid surfaces.

Which of the following statements concerning applications or capabilities of soil moisture measuring devices is (are)true for the tensiometer?

Which of the following expressions in kPa is most apt to characterize the gravitational potential of a clay loam surface soil?

The water content in a soil is known to be .2 m3/m3 and the potential of pure water outside the system is assumed to be 0.If the soil is a clay loam you would calculate the soil water potential (in kPa)to be

Unsaturated water flow _____________.

The osmotic potential is dependent upon the presence of salts and other solutes in the soil.

The Soils Around Us

Formation of Soils From Parent Materials

Soil Classification

Soil Architecture and Physical Properties

Soil and the Hydrologic Cycle

Soil Aeration and Temperature

The Colloidal Fraction: Seat of Soil Chemical and Physical Activity

Soil Acidity

Soils of Dry Regionsalkalinity,salinity and Sodicity

Organisms and Ecology of the Soil

Soil Organic Matter

Nitrogen and Sulfur Economy of Soils

Soil Phosphorus and Potassium

Calcium,magnesium and Trace Elements

Practical Nutrient Management

Soil Erosion and Its Control

Soils and Chemical Pollution

Geographic Information About Soils

Prospects for Global Soil Quality As Affected by Human Activities

Filters

The water content in a soil is known to be .2 m³/m³ and the potential of pure water outside the system is assumed to be 0.If the soil is a clay loam you would calculate the soil water potential (in kPa)to be