Question 1

Application of phosphorus fertilizer usually makes plants more susceptible to diseases.

Accepted Answer

A) True 
 B)False  False

Question 2

Compared to land that is not disturbed by tillage,conventionally plowed cropland usually loses much more ______.

Accepted Answer

A) dissolved P 
B) particulate P 
C) total P 
D) both B and C are correct 
E) none of the above is correct 
A) dissolved P 
B) particulate P 
C) total P 
D) both B and C are correct 
E) none of the above is correct D

Question 3

The term,eutrophication,comes from the Greek word meaning "to suffocate" and connotes anaerobic decomposition in soils.

Accepted Answer

A) True 
 B)False  False

Question 4

The nutrient most often limiting the growth of aquatic plants and algae in unpolluted fresh water lakes is ______.

Accepted Answer

A) N 
B) S 
C) P 
D) K 
E) none of the above 
A) N 
B) S 
C) P 
D) K 
E) none of the above

Question 5

Most soils with a high phosphorus fixing capacity are inherently fertile.

Accepted Answer

A) True 
 B)False

Question 6

In acid soils the principal chemical form of potassium available for plant uptake is ____.

Accepted Answer

A) K2O 
B) H2KO2- 
C) K+ 
D) HKO22- 
E) P- 
A) K2O 
B) H2KO2- 
C) K+ 
D) HKO22- 
E) P-

Question 7

A soil with a very low equilibrium phosphorus concentration (EPC)is likely to be characterized by a very low potential buffering capacity (PBC).

Accepted Answer

A) True 
 B)False

Question 8

Other things being equal,a soil with 30% clay of the ____ type would be expected to have the greatest phosphorus -fixing capacity.

Accepted Answer

A) allophanic 
B) 2:1 
C) 1:1 
D) crystalline iron oxide 
A) allophanic 
B) 2:1 
C) 1:1 
D) crystalline iron oxide

Question 9

Approximately what percentage of the P in surface soils is typically found in organic forms?

Accepted Answer

A) 0.1 to 0.5% 
B) 1 to 5% 
C) 5 to 15% 
D) 25 to 75% 
E) 95 to 98% 
A) 0.1 to 0.5% 
B) 1 to 5% 
C) 5 to 15% 
D) 25 to 75% 
E) 95 to 98%

Question 10

Annual plants deficient in P usually flower and mature more rapidly than P-sufficient plants.

Accepted Answer

A) True 
 B)False

Question 11

The sites in certain clay minerals which fix potassium ions are also capable of fixing which other ion?

Accepted Answer

A) NO3- 
B) NH4+ 
C) H2PO4- 
D) Ca2+ 
E) H+ 
A) NO3- 
B) NH4+ 
C) H2PO4- 
D) Ca2+ 
E) H+

Question 12

For soils with significant pH dependent charge,raising the pH with limestone tends to increase the availability of potassium in the soil.

Accepted Answer

A) True 
 B)False

Question 13

Eroded sediment usually contains about half as much P per kg as does the soil remaining on the eroded site.

Accepted Answer

A) True 
 B)False

Question 14

The amount of both P and K fertilizer applied to US farmland has increased dramatically since 1980 as American farmers attempt to maximize profits and meet record demands for food.

Accepted Answer

A) True 
 B)False

Question 15

Because of the complementary ion effect,potassium is more readily leached from an acid soil than from a neutral soil.

Accepted Answer

A) True 
 B)False

Question 16

If a manager can afford only a limited amount of soluble P fertilizer for a calcareous soil with low phosphorus availability,the best plant growth is likely to be obtained if the P fertilizer is applied _____.

Accepted Answer

A) well in advance of the plant's main period of nutrient uptake 
B) evenly across the entire area to be fertilized and mixed thoroughly with the soil in the root zone 
C) in narrow bands or localized concentrations 
D) in combination with ground limestone 
E) a combination of both B and D would be best 
A) well in advance of the plant's main period of nutrient uptake 
B) evenly across the entire area to be fertilized and mixed thoroughly with the soil in the root zone 
C) in narrow bands or localized concentrations 
D) in combination with ground limestone 
E) a combination of both B and D would be best

Question 17

Compared to the same soil used for cropland,a forested soil would be expected to lose _____ total P to streams draining the watershed.

Accepted Answer

A) less 
B) about the same amount of 
C) more 
A) less 
B) about the same amount of 
C) more

Question 18

In what range of soil pH is phosphorus generally most available to plants?

Accepted Answer

A) 3.5-4.5 
B) 4.5-5.5 
C) 5.5-7.0 
D) 7.0-8.0 
E) >8.0 
A) 3.5-4.5 
B) 4.5-5.5 
C) 5.5-7.0 
D) 7.0-8.0 
E) >8.0

Question 19

Water running off from a bare field whose soil had an EPC of 0.1 mg/L would be expected to be lower in P concentration than runoff from a field whose soil had an EPC of 2 mg/L.

Accepted Answer

A) True 
 B)False

Question 20

Other things being equal,a soil with 30% clay of the ____ type would be expected to have the greatest potassium -fixing capacity.

Accepted Answer

A) allophanic 
B) 2:1 
C) 1:1 
D) crystalline iron oxide 
A) allophanic 
B) 2:1 
C) 1:1 
D) crystalline iron oxide

Application of phosphorus fertilizer usually makes plants more susceptible to diseases.

Compared to land that is not disturbed by tillage,conventionally plowed cropland usually loses much more ______.

The term,eutrophication,comes from the Greek word meaning "to suffocate" and connotes anaerobic decomposition in soils.

The nutrient most often limiting the growth of aquatic plants and algae in unpolluted fresh water lakes is ______.

Most soils with a high phosphorus fixing capacity are inherently fertile.

In acid soils the principal chemical form of potassium available for plant uptake is ____.

A soil with a very low equilibrium phosphorus concentration (EPC)is likely to be characterized by a very low potential buffering capacity (PBC).

Other things being equal,a soil with 30% clay of the ____ type would be expected to have the greatest phosphorus -fixing capacity.

Approximately what percentage of the P in surface soils is typically found in organic forms?

Annual plants deficient in P usually flower and mature more rapidly than P-sufficient plants.

The sites in certain clay minerals which fix potassium ions are also capable of fixing which other ion?

For soils with significant pH dependent charge,raising the pH with limestone tends to increase the availability of potassium in the soil.

Eroded sediment usually contains about half as much P per kg as does the soil remaining on the eroded site.

The amount of both P and K fertilizer applied to US farmland has increased dramatically since 1980 as American farmers attempt to maximize profits and meet record demands for food.

Because of the complementary ion effect,potassium is more readily leached from an acid soil than from a neutral soil.

If a manager can afford only a limited amount of soluble P fertilizer for a calcareous soil with low phosphorus availability,the best plant growth is likely to be obtained if the P fertilizer is applied _____.

Compared to the same soil used for cropland,a forested soil would be expected to lose _____ total P to streams draining the watershed.

In what range of soil pH is phosphorus generally most available to plants?

Water running off from a bare field whose soil had an EPC of 0.1 mg/L would be expected to be lower in P concentration than runoff from a field whose soil had an EPC of 2 mg/L.

Other things being equal,a soil with 30% clay of the ____ type would be expected to have the greatest potassium -fixing capacity.

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

Soil Acidity

Soils of Dry Regionsalkalinity,salinity and Sodicity

Organisms and Ecology of the Soil

Soil Organic Matter

Nitrogen and Sulfur Economy of Soils

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 14: Soil Phosphorus and Potassium

Application of phosphorus fertilizer usually makes plants more susceptible to diseases.

Compared to land that is not disturbed by tillage,conventionally plowed cropland usually loses much more ______.

The term,eutrophication,comes from the Greek word meaning "to suffocate" and connotes anaerobic decomposition in soils.

The nutrient most often limiting the growth of aquatic plants and algae in unpolluted fresh water lakes is ______.

Most soils with a high phosphorus fixing capacity are inherently fertile.

In acid soils the principal chemical form of potassium available for plant uptake is ____.

A soil with a very low equilibrium phosphorus concentration (EPC)is likely to be characterized by a very low potential buffering capacity (PBC).

Other things being equal,a soil with 30% clay of the ____ type would be expected to have the greatest phosphorus -fixing capacity.

Approximately what percentage of the P in surface soils is typically found in organic forms?

Annual plants deficient in P usually flower and mature more rapidly than P-sufficient plants.

The sites in certain clay minerals which fix potassium ions are also capable of fixing which other ion?

For soils with significant pH dependent charge,raising the pH with limestone tends to increase the availability of potassium in the soil.

Eroded sediment usually contains about half as much P per kg as does the soil remaining on the eroded site.

The amount of both P and K fertilizer applied to US farmland has increased dramatically since 1980 as American farmers attempt to maximize profits and meet record demands for food.

Because of the complementary ion effect,potassium is more readily leached from an acid soil than from a neutral soil.

If a manager can afford only a limited amount of soluble P fertilizer for a calcareous soil with low phosphorus availability,the best plant growth is likely to be obtained if the P fertilizer is applied _____.

Compared to the same soil used for cropland,a forested soil would be expected to lose _____ total P to streams draining the watershed.

In what range of soil pH is phosphorus generally most available to plants?

Water running off from a bare field whose soil had an EPC of 0.1 mg/L would be expected to be lower in P concentration than runoff from a field whose soil had an EPC of 2 mg/L.

Other things being equal,a soil with 30% clay of the ____ type would be expected to have the greatest potassium -fixing capacity.

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

Soil Acidity

Soils of Dry Regionsalkalinity,salinity and Sodicity

Organisms and Ecology of the Soil

Soil Organic Matter

Nitrogen and Sulfur Economy of Soils

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