Question 1

The property of cohesion in water stems from the attraction of water molecules for soil solids.

Accepted Answer

A) True 
 B)False  False

Question 2

Capillary movement is made possible by the processes of cohesion and adhesion.

Accepted Answer

A) True 
 B)False  True

Question 3

Plant roots gain access to soil water primarily by the growth of the roots into moist soil.

Accepted Answer

A) True 
 B)False  False

Question 4

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

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 5

Osmotic and matric potentials are commonly negative because the soil water has a lower energy level than that of pure water.

Accepted Answer

A) True 
 B)False

Question 6

The water potential at the field capacity for most soils is in the range of -10 to -30 kPa.

Accepted Answer

A) True 
 B)False

Question 7

At which of the following soil moisture potentials (expressed as kPa)is the soil water held most tightly?

Accepted Answer

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

Question 8

Which of the following statements concerning applications or capabilities of soil moisture measuring devices is (are)true for the use of a drying oven and balance?

Accepted Answer

A) requires "destructive sampling" for each measurement 
B) good to turn on automatic irrigation at -5.0 kPa 
C) used to turn on irrigation when soil moisture potential reaches -20.0 kPa 
D) gives same reading for loamy sand and 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 -5.0 kPa 
C) used to turn on irrigation when soil moisture potential reaches -20.0 kPa 
D) gives same reading for loamy sand and silt loam if both contained 15% moisture 
E) both A and D

Question 9

The hydrogen end of a water molecule is attracted to positively charged cations such as Na+ and Ca2+.

Accepted Answer

A) True 
 B)False

Question 10

The soil water potential is a measure of the potential of a soil to hold water.

Accepted Answer

A) True 
 B)False

Question 11

Two soil samples,A & B,at different soil moisture levels are placed in contact with each other.Water will more likely move from soil A to soil B if their water potentials,expressed in kPa,are:

Accepted Answer

A) A=-5;B=+5 
B) A=-5;B=-5 
C) A=-20;B=-10 
D) A=-30;B=-40 
E) A=-100;B=-50 
A) A=-5;B=+5 
B) A=-5;B=-5 
C) A=-20;B=-10 
D) A=-30;B=-40 
E) A=-100;B=-50

Question 12

The magnetic resonance technique of estimating soil moisture levels can also be used to estimate salt contents.

Accepted Answer

A) True 
 B)False

Question 13

Although the total soil water content of a clay soil is about the same as a nearby well structured silt loam,the clay will likely provide more available water to plants because of its higher volume of small pores.

Accepted Answer

A) True 
 B)False

Question 14

Gypsum or nylon blocks are most useful in estimating the soil water content if the soil is quite dry.

Accepted Answer

A) True 
 B)False

Question 15

Capillarity in soils _____.

Accepted Answer

A) involves both adhesion and cohesion 
B) is enhanced by the symmetrical nature of the water molecule 
C) is independent of the matric potential in soils 
D) is not involved in the process of water uptake from soils 
E) does not account for unsaturated water movement in soils 
A) involves both adhesion and cohesion 
B) is enhanced by the symmetrical nature of the water molecule 
C) is independent of the matric potential in soils 
D) is not involved in the process of water uptake from soils 
E) does not account for unsaturated water movement in soils

Question 16

Soils high in organic matter commonly hold more available water than comparable soils with lower organic matter levels.This is most likely due to what characteristics of the high O.M.soils

Accepted Answer

A) larger micro pore space 
B) lower permanent wilting percentage 
C) higher field capacity 
D) higher capacity of the O.M.to hold water tightly 
E) higher clay content 
A) larger micro pore space 
B) lower permanent wilting percentage 
C) higher field capacity 
D) higher capacity of the O.M.to hold water tightly 
E) higher clay content

Question 17

Water molecules have polarity primarily because each contains two H atoms and only one O atom.

Accepted Answer

A) True 
 B)False

Question 18

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

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 19

Which of the following means of estimating soil water levels gives a direct measurement of the water content?

Accepted Answer

A) gypsum blocks 
B) neutron scattering 
C) gravimetric determinations 
D) tensiometer 
E) pressure membrane 
A) gypsum blocks 
B) neutron scattering 
C) gravimetric determinations 
D) tensiometer 
E) pressure membrane

Question 20

Water will move from one site in a soil with a water potential of -5 kPa to an adjacent site with a water potential of -40 kPa.

Accepted Answer

A) True 
 B)False

The property of cohesion in water stems from the attraction of water molecules for soil solids.

Capillary movement is made possible by the processes of cohesion and adhesion.

Plant roots gain access to soil water primarily by the growth of the roots into moist soil.

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

Osmotic and matric potentials are commonly negative because the soil water has a lower energy level than that of pure water.

The water potential at the field capacity for most soils is in the range of -10 to -30 kPa.

At which of the following soil moisture potentials (expressed as kPa)is the soil water held most tightly?

Which of the following statements concerning applications or capabilities of soil moisture measuring devices is (are)true for the use of a drying oven and balance?

The hydrogen end of a water molecule is attracted to positively charged cations such as Na⁺ and Ca²⁺.

The soil water potential is a measure of the potential of a soil to hold water.

Two soil samples,A & B,at different soil moisture levels are placed in contact with each other.Water will more likely move from soil A to soil B if their water potentials,expressed in kPa,are:

The magnetic resonance technique of estimating soil moisture levels can also be used to estimate salt contents.

Although the total soil water content of a clay soil is about the same as a nearby well structured silt loam,the clay will likely provide more available water to plants because of its higher volume of small pores.

Gypsum or nylon blocks are most useful in estimating the soil water content if the soil is quite dry.

Capillarity in soils _____.

Soils high in organic matter commonly hold more available water than comparable soils with lower organic matter levels.This is most likely due to what characteristics of the high O.M.soils

Water molecules have polarity primarily because each contains two H atoms and only one O atom.

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

Which of the following means of estimating soil water levels gives a direct measurement of the water content?

Water will move from one site in a soil with a water potential of -5 kPa to an adjacent site with a water potential of -40 kPa.

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

The property of cohesion in water stems from the attraction of water molecules for soil solids.

Capillary movement is made possible by the processes of cohesion and adhesion.

Plant roots gain access to soil water primarily by the growth of the roots into moist soil.

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

Osmotic and matric potentials are commonly negative because the soil water has a lower energy level than that of pure water.

The water potential at the field capacity for most soils is in the range of -10 to -30 kPa.

At which of the following soil moisture potentials (expressed as kPa)is the soil water held most tightly?

Which of the following statements concerning applications or capabilities of soil moisture measuring devices is (are)true for the use of a drying oven and balance?

The hydrogen end of a water molecule is attracted to positively charged cations such as Na+ and Ca2+.

The soil water potential is a measure of the potential of a soil to hold water.

Two soil samples,A & B,at different soil moisture levels are placed in contact with each other.Water will more likely move from soil A to soil B if their water potentials,expressed in kPa,are:

The magnetic resonance technique of estimating soil moisture levels can also be used to estimate salt contents.

Although the total soil water content of a clay soil is about the same as a nearby well structured silt loam,the clay will likely provide more available water to plants because of its higher volume of small pores.

Gypsum or nylon blocks are most useful in estimating the soil water content if the soil is quite dry.

Capillarity in soils _____.

Soils high in organic matter commonly hold more available water than comparable soils with lower organic matter levels.This is most likely due to what characteristics of the high O.M.soils

Water molecules have polarity primarily because each contains two H atoms and only one O atom.

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

Which of the following means of estimating soil water levels gives a direct measurement of the water content?

Water will move from one site in a soil with a water potential of -5 kPa to an adjacent site with a water potential of -40 kPa.

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 hydrogen end of a water molecule is attracted to positively charged cations such as Na⁺ and Ca²⁺.