Question 1

If you want to quickly (in just a few days) increase the pH of a soil from 5.5 to 7.0, which of the following would you use?

Accepted Answer

A)  sawdust 
B)  calcitic limestone 
C)  dolomitic limestone 
D)  burned lime 
E)  ammonium nitrate 
A)  sawdust 
B)  calcitic limestone 
C)  dolomitic limestone 
D)  burned lime 
E)  ammonium nitrate

Question 2

A homeowner in New Mexico attempted to grow azaleas in a well drained soil (pH 7.5) but the plants were stunted and the leaves were yellow. What is the most likely cause of this constraint?

Accepted Answer

A)  P deficiency 
B)  Mn toxicity 
C)  Fe deficiency 
D)  Ca toxicity 
E)  Na 
A)  P deficiency 
B)  Mn toxicity 
C)  Fe deficiency 
D)  Ca toxicity 
E)  Na

Question 3

The presence of neutral salts in salt-affected soils helps keep the pH from rising above 8.5.

Accepted Answer

A) True 
 B)False

Question 4

Sodic soils are sometimes referred to as white alkalis because of the white salt crusts that appear on the surface.

Accepted Answer

A) True 
 B)False

Question 5

If you want to grow azaleas in a soil that initially has a pH of 6.5 and have been told that you should apply sulfur to reduce the soil pH, you would likely need more sulfur if the soil is a clay Vertisol than if it is an clay Ultisol.

Accepted Answer

A) True 
 B)False

Question 6

Sodic soils generally have better physical conditions than either saline or saline-sodic soils.

Accepted Answer

A) True 
 B)False

Question 7

Poor plant growth in a well-drained irrigated soil in an arid region (pH=8.0) is most likely due to ________.

Accepted Answer

A)  manganese toxicity 
B)  iron deficiency 
C)  phosphate toxicity 
D)  calcium toxicity 
E)  molybdenum deficiency 
A)  manganese toxicity 
B)  iron deficiency 
C)  phosphate toxicity 
D)  calcium toxicity 
E)  molybdenum deficiency

Question 8

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

Accepted Answer

A) True 
 B)False

Question 9

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

Accepted Answer

A) True 
 B)False

Question 10

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 11

Sulfur can be used to increase soil acidity and to reduce alkalinity.

Accepted Answer

A) True 
 B)False

Question 12

Saline-sodic soils have electrical conductivities greater than 4 dS/m and a sodium adsorption ratio of less than 13.

Accepted Answer

A) True 
 B)False

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

Available phosphorus levels are constrained in alkaline and salt-affected soils because of _____.

Accepted Answer

A)  high iron and aluminum levels 
B)  high exchangeable sodium levels 
C)  high calcium and magnesium levels 
D)  high manganese levels 
E)  low hydrogen ion levels 
A)  high iron and aluminum levels 
B)  high exchangeable sodium levels 
C)  high calcium and magnesium levels 
D)  high manganese levels 
E)  low hydrogen ion levels

Question 15

Normal alkaline soils are characterized by all but which one of the following?

Accepted Answer

A)  low levels of available iron 
B)  high levels of molybdenum 
C)  high levels of exchangeable sodium 
D)  low levels of available manganese 
E)  low levels of available boron 
A)  low levels of available iron 
B)  high levels of molybdenum 
C)  high levels of exchangeable sodium 
D)  low levels of available manganese 
E)  low levels of available boron

Question 16

Attempts to leach the excess salts from a saline-sodic soil resulted in a marked reduction of crop yields. To what is this most likely due?

Accepted Answer

A)  deficiency of iron and manganese 
B)  increase in percentage sodium saturation 
C)  removal of Ca2+ and Mg2+ ions from the exchange complex 
D)  increase in the soil pH 
E)  increase in the Al3+ concentration 
A)  deficiency of iron and manganese 
B)  increase in percentage sodium saturation 
C)  removal of Ca2+ and Mg2+ ions from the exchange complex 
D)  increase in the soil pH 
E)  increase in the Al3+ concentration

Question 17

The presence of neutral salts in an alkaline soil has a tendency to increase the pH of the soil.

Accepted Answer

A) True 
 B)False

Question 18

The higher the cation exchange capacity of a soil, the greater is its buffer capacity.

Accepted Answer

A) True 
 B)False

Question 19

Which of the following comparisons of the three different classes of salt-affected soils is correct?

Accepted Answer

A)  Sodic soils generally have the lowest pH. 
B)  Saline soils are generally higher in soluble salts than saline-sodic soils. 
C)  Sodic soils generally have the highest EC levels. 
D)  The pH of saline soils is generally above 8.5. 
E)  Sodic soils are commonly formed by leaching saline-sodic soils. 
A)  Sodic soils generally have the lowest pH. 
B)  Saline soils are generally higher in soluble salts than saline-sodic soils. 
C)  Sodic soils generally have the highest EC levels. 
D)  The pH of saline soils is generally above 8.5. 
E)  Sodic soils are commonly formed by leaching saline-sodic soils.

Question 20

The cation exchange capacities of alkaline soils are commonly lower than those of comparable soils in humid regions.

Accepted Answer

A) True 
 B)False

If you want to quickly (in just a few days) increase the pH of a soil from 5.5 to 7.0, which of the following would you use?

A homeowner in New Mexico attempted to grow azaleas in a well drained soil (pH 7.5) but the plants were stunted and the leaves were yellow. What is the most likely cause of this constraint?

The presence of neutral salts in salt-affected soils helps keep the pH from rising above 8.5.

Sodic soils are sometimes referred to as white alkalis because of the white salt crusts that appear on the surface.

If you want to grow azaleas in a soil that initially has a pH of 6.5 and have been told that you should apply sulfur to reduce the soil pH, you would likely need more sulfur if the soil is a clay Vertisol than if it is an clay Ultisol.

Sodic soils generally have better physical conditions than either saline or saline-sodic soils.

Poor plant growth in a well-drained irrigated soil in an arid region (pH=8.0) is most likely due to ________.

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

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

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

Sulfur can be used to increase soil acidity and to reduce alkalinity.

Saline-sodic soils have electrical conductivities greater than 4 dS/m and a sodium adsorption ratio of less than 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.

Available phosphorus levels are constrained in alkaline and salt-affected soils because of _____.

Normal alkaline soils are characterized by all but which one of the following?

Attempts to leach the excess salts from a saline-sodic soil resulted in a marked reduction of crop yields. To what is this most likely due?

The presence of neutral salts in an alkaline soil has a tendency to increase the pH of the soil.

The higher the cation exchange capacity of a soil, the greater is its buffer capacity.

Which of the following comparisons of the three different classes of salt-affected soils is correct?

The cation exchange capacities of alkaline soils are commonly lower than those of comparable soils in humid regions.

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

Organisms and Ecology of the Soil

Soil Organic Matter Overview

Nutrient Cycles and Soil Fertility

Practical Nutrient Management

Soil Erosion and Its Control

Soils and Chemical Pollution

Filters

Exam 9: Soil Acidity, Alkalinity, Aridity and Salinity

If you want to quickly (in just a few days) increase the pH of a soil from 5.5 to 7.0, which of the following would you use?

A homeowner in New Mexico attempted to grow azaleas in a well drained soil (pH 7.5) but the plants were stunted and the leaves were yellow. What is the most likely cause of this constraint?

The presence of neutral salts in salt-affected soils helps keep the pH from rising above 8.5.

Sodic soils are sometimes referred to as white alkalis because of the white salt crusts that appear on the surface.

If you want to grow azaleas in a soil that initially has a pH of 6.5 and have been told that you should apply sulfur to reduce the soil pH, you would likely need more sulfur if the soil is a clay Vertisol than if it is an clay Ultisol.

Sodic soils generally have better physical conditions than either saline or saline-sodic soils.

Poor plant growth in a well-drained irrigated soil in an arid region (pH=8.0) is most likely due to ________.

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

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

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

Sulfur can be used to increase soil acidity and to reduce alkalinity.

Saline-sodic soils have electrical conductivities greater than 4 dS/m and a sodium adsorption ratio of less than 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.

Available phosphorus levels are constrained in alkaline and salt-affected soils because of _____.

Normal alkaline soils are characterized by all but which one of the following?

Attempts to leach the excess salts from a saline-sodic soil resulted in a marked reduction of crop yields. To what is this most likely due?

The presence of neutral salts in an alkaline soil has a tendency to increase the pH of the soil.

The higher the cation exchange capacity of a soil, the greater is its buffer capacity.

Which of the following comparisons of the three different classes of salt-affected soils is correct?

The cation exchange capacities of alkaline soils are commonly lower than those of comparable soils in humid regions.

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

Organisms and Ecology of the Soil

Soil Organic Matter Overview

Nutrient Cycles and Soil Fertility

Practical Nutrient Management

Soil Erosion and Its Control

Soils and Chemical Pollution

Filters