Section 1 - Basic Soil Fertility and Nutrient Limitations Flashcards
Human diets come from:
plants
animals
plants and animals
solar radiation
plants and animals
Fresh and saltwater food sources (all that originate in waters such as fish, salmon, etc.,) contain nutrients that ultimately originate from soluble and sediment-bound nutrients deposited in surface waters from surface and subsurface runoff.
True
False
True
The earth has plenty of arable farming lands that can adequately feed the increasing human population even if it increases unchecked at its current rate without worrying about increasing agricultural productivity.
True
False
False
According to the law of the minimum described by Sprengel and Liebig, correcting the most limiting nutrient will increase yield indefinitely.
True
False
False
The human population is predicted to be ___________ billion at 2050.
8
4
9
20
9
All aqueous solutions in plants and soil solutions must remain electronically neutral.
True
False
True
Applying limestone to soil sesquioxides and kaolinite will \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ soil CEC. increase decrease has no effect none of the above
increase
Relative adsorption strength (lyotropic series) of cations to negatively charged soil colloid can be arrayed as:
Al+3>Ca+2>Mg+2>K+1= Na+1=H+1=NH4+
True
False
False
Soil buffering capacity is generally defined as: ratio of CEC/AEC effective CEC resistance to change -log(H+)
-log(H+)
Active and passive ion transports in plants do not require ATP energy expenditure.
True
False
False
Since charge neutrality must be maintained in soil solution during leaching, one mole of NO3-1 will be counterbalanced with 1 mole of Ca+2.
True
False
False
Which of the following will produce a net mole H+ / mole of N in soil?
NH3 volatilization
N denitrification
oxidation of NH4+
fertilizing with KNO3
oxidation of NH4+
Adding CaSO4.2H2O (gypsum) to a soil does not increase soil pH because it does not have anions such as O-, OH-, CO3- and others that will neutralize the H+ in soil solution.
True
False
True
Soil testing labs use __________________ values to determine the quantity of lime that needs to be added to soil.
water pH
buffer pH
1M KCl soil solution pH
EC (electrical conductivity)
buffer pH
Which of the following is not a soil acidifying material?
S
(Al)2(SO4)3
FeSO4
CaSiO3
CaSiO3
No nitrogen, no life has merit because of the essential function of N containing in all living cells.
True
False
True
A form of N taken up by plants includes:
NH4+
NO3-
soil organic N
all of the above
all of the above
Which of the following doesn’t include N loss in the N-cycle?
NH4-fixation by clay
N2-fixation by legumes
NO3- leaching
N immobilization
N2-fixation by legumes
A nitrification inhibitor blocks the conversion of:
NH4+ to NO3-
NO3- to NH4+
NH4+ to N2
NO3- to N2
NH4+ to NO3-
Organic residues and manures have a comparable N percentage as inorganic N fertilizer, but their rate of N release is significantly less.
True
False
False
_________ worldwide are affected by famine
15-20 million
_________ worldwide affected by malnutrition
1 Billion
Malnutrition and Famine are the most predominant in ____ and ____
sub-Saharan Africa and Asia
_____ today’s world population
7.9e9
_____ world population by ____
9.0e9
2050
In the next __ years, consumption of cereal will increase by ___%.
40
50
In the next __ years, meat consumption will ______.
40
double
In the next __ years, most projected increases will occur in ____ and ____
40
China
India
Agricultural land will _______ but the population and food production will ______
stabilise
increase
__% of total world land area is cropland
12
Per capita, cropland use decreased nearly __% between ____ and ____
50
1960
2007
Global food production must increase by __% by ____ to meet our needs
70
2050
U.S. cereal exports currently represent about ___% of total world cereal production
4.3
U.S. cereal production will have to dramatically increase over the next several decades to keep pace with world demand.
True
List 5 reasons why U.S. crop yields have increased greatly over the last 50 years
- Soil and Water conservation
- Pest and Soil Management
- Development of fertilizers
- Development of plants and hybrid varieties
- Cultural practices
Growth in world fertilizer use was nearly ___ greater than that of the USA in the last decade
60X
Sprengel & Liebig’s Law of the Minimum
- Crop/production yield is proportional to the amount of the most limiting factor
- Once a nutrient has been corrected then yield will increase to the next limiting factor
3 factors Law of the Minimum can be applied to other than nutrients
- Crop variety
- Planting time and conditions
- Water availability
3 factors that determine an element is considered essential to plant growth and develop if
- The element is directly involved in the nutrition of the plant
- A deficiency makes it impossible for the plant to complete its life cycle
- A deficiency is specific to the element and can only be prevented or corrected by supplying the element.
What are the 3 factors of the Steinberg Effect?
- Under severe deficiency, rapid increases in yield with added nutrient can cause a small decrease in nutrient concentration
- When the concentration reaches the critical range, plant yield is generally maximized
- Increases in nutrient concentration above the critical range indicate that the plant is absorbing nutrients above that needed for maximum yield, commonly called luxury consumption.
Define the 4 terms used to describe the nutrient levels in plants.
- Deficient: When an element is low enough to limit yield and deficiency symptoms are visible
- Critical Range: The nutrient concentration is below which a yield response to added nutrients
- Sufficient: Nutrient concentration range in which added nutrient will not increase yield but can increase nutrient concentration
- Excessive or Toxic: When the concentration of essential or other elements is high enough to reduce plant growth or yield
(17) elements essential to plant growth
3 - Most abundant non-minerals
6 - Primary and Secondary Micronutrients
8 - Micronutrients
COH
NPK SCaMg
MnMoClB FeZnCuNi
Human diets come from plants and animals
True
Fresh and saltwater food sources (all that originate in waters such as fish, salmon, etc.,) contain nutrients that ultimately originate from soluble and sediment-bound nutrients deposited in surface waters from surface and subsurface runoff.
True
The earth does not have plenty of arable farming lands that can adequately feed the increasing human population even if it increases unchecked at its current rate without worrying about increasing agricultural productivity.
True
The human population is predicted to be 9 billion at 2050.
True
