Question 1

The drainage of some coastal wetland soils results in high pH due to underlying lime deposits.

Accepted Answer

A) True 
 B)False  False

Question 2

Iron and manganese are commonly deficient in very acid soils.

Accepted Answer

A) True 
 B)False  False

Question 3

The exchange complexes of strongly acid (pH 4.5)mineral soils are saturated mainly with _____.

Accepted Answer

A) exchangeable H+ ions 
B) exchangeable Al3+ ions 
C) exchangeable Al(OH2)+ ions 
D) tightly bound H+ ions 
E) tightly bound Al3+ ions 
A) exchangeable H+ ions 
B) exchangeable Al3+ ions 
C) exchangeable Al(OH2)+ ions 
D) tightly bound H+ ions 
E) tightly bound Al3+ ions B

Question 4

Which of the following does not describe aluminum hydroxy ions (such as Al(OH)2+)in the soil?

Accepted Answer

A) They are more prominent in acid than in neutral soils. 
B) They affect the pH of the soil solution through hydrolysis. 
C) They block negative sites on some clays thereby reducing the cation exchange capacity. 
D) They influence the swelling of some clays by entering into the interlayer spaces. 
E) They are commonly applied to help reduce the soil pH for acid-loving plants. 
A) They are more prominent in acid than in neutral soils. 
B) They affect the pH of the soil solution through hydrolysis. 
C) They block negative sites on some clays thereby reducing the cation exchange capacity. 
D) They influence the swelling of some clays by entering into the interlayer spaces. 
E) They are commonly applied to help reduce the soil pH for acid-loving plants.

Question 5

In humid regions repeat applications of limestone are needed after a few years primarily because of ____.

Accepted Answer

A) the release of aluminum ions from the structure of silicate clays 
B) the annual loss of calcium and magnesium in drainage waters 
C) increases in soil acidity from acid rain 
D) increased rates of formation of carbonic acid (H2CO3) 
E) increases in phosphate fertilization 
A) the release of aluminum ions from the structure of silicate clays 
B) the annual loss of calcium and magnesium in drainage waters 
C) increases in soil acidity from acid rain 
D) increased rates of formation of carbonic acid (H2CO3) 
E) increases in phosphate fertilization

Question 6

Under which of the following conditions would you favor a finely ground dolomitic limestone as your choice of a liming material?

Accepted Answer

A) need for a rapid reaction with the soil 
B) need to provide magnesium in addition to calcium 
C) need for a material with a low shipping cost 
D) need to obtain a high soil pH 
E) need to significantly reduce the exchangeable Al3+ level in the soil 
A) need for a rapid reaction with the soil 
B) need to provide magnesium in addition to calcium 
C) need for a material with a low shipping cost 
D) need to obtain a high soil pH 
E) need to significantly reduce the exchangeable Al3+ level in the soil

Question 7

A soil has a maximum potential cation exchange capacity of 30 cmolc/kg and has a 50% acid saturation.If you want to decrease the percentage acid saturation to 10%,how many cmolc of calcium would it take to replace the exchangeable acid cations per kg of soil? Assume all the calcium exchanged with aluminum.

Accepted Answer

A) 30 
B) 40 
C) 6 
D) 12 
E) 5 
A) 30 
B) 40 
C) 6 
D) 12 
E) 5

Question 8

The drainage of certain wetlands has resulted in extreme soil acidity.This is due primarily to which of the following processes that take place when the soil is drained?

Accepted Answer

A) oxidation of organic materials to produce organic acids 
B) reduction of iron to low valent states that stimulate acidity 
C) release of nitric acid due to oxidation of nitrogen compounds 
D) high redox potential characteristic of aerated soils 
E) oxidation of sulfur-bearing minerals that produces sulfuric acid 
A) oxidation of organic materials to produce organic acids 
B) reduction of iron to low valent states that stimulate acidity 
C) release of nitric acid due to oxidation of nitrogen compounds 
D) high redox potential characteristic of aerated soils 
E) oxidation of sulfur-bearing minerals that produces sulfuric acid

Question 9

Among the soils of which order would you most likely find the highest buffering capacities?

Accepted Answer

A) Alfisols 
B) Vertisols 
C) Oxisols 
D) Spodosols 
E) Ultisols 
A) Alfisols 
B) Vertisols 
C) Oxisols 
D) Spodosols 
E) Ultisols

Question 10

Fungi are much more sensitive to strong acid conditions than are bacteria or actinomycetes.

Accepted Answer

A) True 
 B)False

Question 11

An acid soil is known to contain toxic quantities of a certain plant nutrient.Which of these essential elements is it most likely to be?

Accepted Answer

A) nitrogen 
B) manganese 
C) phosphorus 
D) molybdenum 
E) boron 
A) nitrogen 
B) manganese 
C) phosphorus 
D) molybdenum 
E) boron

Question 12

Which of the following would likely grow best on a soil with a pH of 6.0?

Accepted Answer

A) alfalfa 
B) sweet clover 
C) tomatoes 
D) blueberries 
E) cranberries 
A) alfalfa 
B) sweet clover 
C) tomatoes 
D) blueberries 
E) cranberries

Question 13

If you wanted to quickly increase the pH of a soil to 7.5 to combat a disease in cabbages you are about to plant you should use hydrated lime rather than ground limestone.

Accepted Answer

A) True 
 B)False

Question 14

The cation exchange capacity of humus increases if pH increases.

Accepted Answer

A) True 
 B)False

Question 15

Active soil acidity is a measure of the H+ ion activity in the soil solution.

Accepted Answer

A) True 
 B)False

Question 16

Soil reaction indicates the degree of acidity or alkalinity in a soil.

Accepted Answer

A) True 
 B)False

Question 17

You are using pure limestone (CaCO3)to provide the calcium needed to exchange with acid cations in a soil with a maximum potential cation exchange capacity of 20 cmolc/kg.How many kg of this limestone would you need to add to a hectare furrow slice (2.0 x 106 kg)to reduce the percentage acid saturation from 40 to 10%,assuming that all the calcium added exchanged with aluminum or hydrogen ions?

Accepted Answer

A) 20,000 
B) 50,000 
C) 12,000 
D) 6,000 
E) 8,000 
A) 20,000 
B) 50,000 
C) 12,000 
D) 6,000 
E) 8,000

Question 18

Residual soil acidity is that acidity remaining in the soil after limestone has been applied.

Accepted Answer

A) True 
 B)False

Question 19

The buildup of excess salts in irrigated soils can result in increased pH if the salts are high in sodium bicarbonate.

Accepted Answer

A) True 
 B)False

Question 20

When the soil pH = 5.3,manganese is more likely than aluminum to be toxic to plants.

Accepted Answer

A) True 
 B)False

The drainage of some coastal wetland soils results in high pH due to underlying lime deposits.

Iron and manganese are commonly deficient in very acid soils.

The exchange complexes of strongly acid (pH 4.5)mineral soils are saturated mainly with _____.

Which of the following does not describe aluminum hydroxy ions (such as Al(OH)₂⁺)in the soil?

In humid regions repeat applications of limestone are needed after a few years primarily because of ____.

Under which of the following conditions would you favor a finely ground dolomitic limestone as your choice of a liming material?

The drainage of certain wetlands has resulted in extreme soil acidity.This is due primarily to which of the following processes that take place when the soil is drained?

Among the soils of which order would you most likely find the highest buffering capacities?

Fungi are much more sensitive to strong acid conditions than are bacteria or actinomycetes.

An acid soil is known to contain toxic quantities of a certain plant nutrient.Which of these essential elements is it most likely to be?

Which of the following would likely grow best on a soil with a pH of 6.0?

If you wanted to quickly increase the pH of a soil to 7.5 to combat a disease in cabbages you are about to plant you should use hydrated lime rather than ground limestone.

The cation exchange capacity of humus increases if pH increases.

Active soil acidity is a measure of the H⁺ ion activity in the soil solution.

Soil reaction indicates the degree of acidity or alkalinity in a soil.

Residual soil acidity is that acidity remaining in the soil after limestone has been applied.

The buildup of excess salts in irrigated soils can result in increased pH if the salts are high in sodium bicarbonate.

When the soil pH = 5.3,manganese is more likely than aluminum to be toxic to plants.

The Soils Around Us

Formation of Soils From Parent Materials

Soil Classification

Soil Architecture and Physical Properties

Soil Water: Characteristics and Behavior

Soil and the Hydrologic Cycle

Soil Aeration and Temperature

The Colloidal Fraction: Seat of Soil Chemical and Physical Activity

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 9: Soil Acidity

The drainage of some coastal wetland soils results in high pH due to underlying lime deposits.

Iron and manganese are commonly deficient in very acid soils.

The exchange complexes of strongly acid (pH 4.5)mineral soils are saturated mainly with _____.

Which of the following does not describe aluminum hydroxy ions (such as Al(OH)2+)in the soil?

In humid regions repeat applications of limestone are needed after a few years primarily because of ____.

Under which of the following conditions would you favor a finely ground dolomitic limestone as your choice of a liming material?

The drainage of certain wetlands has resulted in extreme soil acidity.This is due primarily to which of the following processes that take place when the soil is drained?

Among the soils of which order would you most likely find the highest buffering capacities?

Fungi are much more sensitive to strong acid conditions than are bacteria or actinomycetes.

An acid soil is known to contain toxic quantities of a certain plant nutrient.Which of these essential elements is it most likely to be?

Which of the following would likely grow best on a soil with a pH of 6.0?

If you wanted to quickly increase the pH of a soil to 7.5 to combat a disease in cabbages you are about to plant you should use hydrated lime rather than ground limestone.

The cation exchange capacity of humus increases if pH increases.

Active soil acidity is a measure of the H+ ion activity in the soil solution.

Soil reaction indicates the degree of acidity or alkalinity in a soil.

Residual soil acidity is that acidity remaining in the soil after limestone has been applied.

The buildup of excess salts in irrigated soils can result in increased pH if the salts are high in sodium bicarbonate.

When the soil pH = 5.3,manganese is more likely than aluminum to be toxic to plants.

The Soils Around Us

Formation of Soils From Parent Materials

Soil Classification

Soil Architecture and Physical Properties

Soil Water: Characteristics and Behavior

Soil and the Hydrologic Cycle

Soil Aeration and Temperature

The Colloidal Fraction: Seat of Soil Chemical and Physical Activity

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

Which of the following does not describe aluminum hydroxy ions (such as Al(OH)₂⁺)in the soil?

Active soil acidity is a measure of the H⁺ ion activity in the soil solution.