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Quiz am Soil Science Final - Quiz, erstellt von Meagan F am 10/12/2016.

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Soil Science Final - Quiz

Frage 1 von 106

1

In nature, beneficial mycorrhizae form with the roots of ____.

Wähle eine der folgenden:

  • coniferous trees

  • grasses

  • legumes

  • broad leaf trees

  • all of these

Erklärung

Frage 2 von 106

1

The second most important biological process on earth is

Wähle eine der folgenden:

  • photosynthesis

  • nitrogen volatilization

  • sulfur oxidation

  • nitrification

  • none of the above

Erklärung

Frage 3 von 106

1

The site of nutrient transfer between a plant and an ectomycorrhizal fungus is called the _____.

Wähle eine der folgenden:

  • arbuscule

  • Hartig net

  • mantle

  • absorptive hyphae

Erklärung

Frage 4 von 106

1

Nitrogenase enzyme activity is inhibited by:

Wähle eine der folgenden:

  • high oxygen

  • low available C

  • low pH

  • all of these

  • none of these

Erklärung

Frage 5 von 106

1

The site of nutrient transfer between a plant and an endomycorrhizal fungus is called the ____.

Wähle eine der folgenden:

  • arbuscule

  • Hartig net

  • mantle

  • absorptive hypphate

Erklärung

Frage 6 von 106

1

Wähle von der Dropdown-Liste, um den Text zu vervollständigen.

Nitrogen fixing bacteria move through a(n) ( root cortex, infection thread, stomate ) to the ( nodules, stem ) which are produced by the plant in the cortical cells, where they reproduce and begin to fix nitrogen.

Erklärung

Frage 7 von 106

1

During symbiotic nitrogen fixation, the plant benefits by:

Wähle eine der folgenden:

  • gaining nitrogen

  • gaining carbon

  • getting protection against pathogens

  • the acidification of the root zone

  • none of the above

Erklärung

Frage 8 von 106

1

Ectomycorrhizae:

Wähle eine der folgenden:

  • penetrate the root cortex cells and produce tree-like structures for nutrient exchange with the plant

  • create a net-like structure between root cortex cells and on the outside of the roots

  • create nodules inside root cells where nutrient exchange with the plant takes place

  • kill the roots and reduce plant nutrient uptake

Erklärung

Frage 9 von 106

1

Wähle von der Dropdown-Liste, um den Text zu vervollständigen.

( Leghemoglobin, Hemoglobin ) is produced by the ( plant, bacteria ) to maintain ( high, low ) levels of ( carbon dioxide, oxygen ) required for nitrogenase activity.

Erklärung

Frage 10 von 106

1

The main benefit for the plant of having a symbiotic relationship with mycorrhizal fungi is:

Wähle eine der folgenden:

  • increased nitrogen availability

  • increased root surface area for nutrient uptake

  • protection against root pathogens

  • increased oxygen in the root for cellular respiration

Erklärung

Frage 11 von 106

1

Nitrogen is a component of which essential plant compounds?

Wähle eine der folgenden:

  • chlorophyll

  • enzymes

  • DNA

  • all of the above

Erklärung

Frage 12 von 106

1

At low soil pH,

Wähle eine der folgenden:

  • all nutrients are at deficient levels

  • Ca, Mg, and P are at deficient levels, and Al is at toxic levels

  • Most nutrients tend to be at toxic levels

  • Ca, Mg, and P are at toxic levels, and Al is fixed in insoluble compounds

  • All nutrient elements are at levels that support good plant growth

Erklärung

Frage 13 von 106

1

Wähle von der Dropdown-Liste, um den Text zu vervollständigen.

Soils in humid climates tend to acidify ( faster___, slower ) than soils in dry climates because there is ( more, less ) leaching of ( acidic, basic ) cations.

Erklärung

Frage 14 von 106

1

Which of the following would not be a liming material?

Wähle eine der folgenden:

  • MgCO₃

  • Ca(OH)₂

  • CaSiO₂

  • CaSO₄

  • All of these are lime

Erklärung

Frage 15 von 106

1

Wähle von der Aufklappliste, um den Text zu vervollständigen.

The type of microorganism that becomes dominant in the final stage of decomposition and breaks down chitin, cellulose, lignins, and waxes is ( Fungi, protists, actinomycetes, bacteria ).

Erklärung

Frage 16 von 106

1

Predators that help regulate decomposition rate include:

Wähle eine der folgenden:

  • Protists and nematodes

  • Bacteria and fungi

  • Actinomycetes

  • Termites

Erklärung

Frage 17 von 106

1

Humus is in which pool of organic matter?

Wähle eine der folgenden:

  • active

  • slow

  • rapid

  • passive

Erklärung

Frage 18 von 106

1

The humus pool of soil organic matter

Wähle eine oder mehr der folgenden:

  • has a C:N of about 10:1

  • decomposes within 1 to 2 years

  • is very stable

  • decomposes within 5 to 10 years

Erklärung

Frage 19 von 106

1

Which of the following statements is true about soil organic matter?

Wähle eine der folgenden:

  • It cannot be increased in the soil indefinitely

  • Application to the soil always leads to lots of immediately available nitrogen

  • It breaks down more rapidly is the soil is tilled

  • A and B only

  • A and C only

Erklärung

Frage 20 von 106

1

The rate of organic matter decomposition is fastest under which of the following set of conditions?

Wähle eine der folgenden:

  • Acid pH, moist soils, warm temperatures, good aeration, residues left on soil surface

  • Alkaline pH, dry soils, cool temperatures, good aeration, residues incorporated into soil

  • Neutral pH, moist soils, warm temperatures, poor aeration, residues left on soil surface

  • Neutral pH, moist soils, warm temperatures, good aeration, residues incorporated

Erklärung

Frage 21 von 106

1

Which of the follow C:N ratios will most likely result in a moderate rate of organic matter breakdown with no short term changes in the soil nitrogen?

Wähle eine der folgenden:

  • 5:1

  • 25:1

  • 100:1

  • 1000:1

Erklärung

Frage 22 von 106

1

Long-term tillage tends to reduce the amount of organic matter in a soil because

Wähle eine oder mehr der folgenden:

  • tillage incorporates residues into the soil

  • tillage reduces soil aeration

  • tillage reduces soil erosion

  • tillage reintroduces oxygen into the soil

Erklärung

Frage 23 von 106

1

Wähle von der Dropdown-Liste, um den Text zu vervollständigen.

In aerobic respiration by microbes, ( N₂, CO₂, O₂ ) is absorbed, and ( O₂, N₂, CO₂ ) is released.

Erklärung

Frage 24 von 106

1

Soil organisms that reproduce rapidly and degrade the simple compounds found in fresh organic matter added to the soil are the ___.

Wähle eine der folgenden:

  • fungi

  • rotifers

  • bacteria

  • earthworms

Erklärung

Frage 25 von 106

1

An important function of humus is to:

Wähle eine der folgenden:

  • help establish and maintain strong granular soil structure

  • hold onto water very tightly so that only soil microorganisms can use it

  • provide large quantities of quickly available plant nutrients

  • provide easily degradable carbon compounds for soil microorganisms

Erklärung

Frage 26 von 106

1

Which of the following management practices would most likely be necessary if growing food crops on Spodosols?

Wähle eine der folgenden:

  • frequent use of soil tillage and conservation

  • use of erosion control measures such as terracing

  • addition of liming agents

  • supplying water through irrigation

Erklärung

Frage 27 von 106

1

Gelisols:

Wähle eine der folgenden:

  • are old, deeply weathered soils developed from intrusive volcanic rock

  • contain a permafrost layer within the top 2 meters

  • contain slickensides

  • include all soils with a histic epipedon

  • none of the above

Erklärung

Frage 28 von 106

1

Slickensides may be found in:

Wähle eine der folgenden:

  • vertisols

  • mollisols

  • andisols

  • oxisols

  • none of the above

Erklärung

Frage 29 von 106

1

Andisols:

Wähle eine der folgenden:

  • are old, deeply weathered soils developed from intrusive volcanic rock

  • contain slickensides

  • form on unstable landscape positions undergoing erosion and deposition

  • contain a permafrost layer within the top 2 meters

  • none of the above

Erklärung

Frage 30 von 106

1

Ultisols:

Wähle eine der folgenden:

  • form on unstable landscape positions undergoing erosion and deposition

  • form on old, stable land surfaces in warm humid climates

  • are the most weathered soils

  • contain slickensides

Erklärung

Frage 31 von 106

1

The role of soil animals in organic matter decomposition is to:

Wähle eine oder mehr der folgenden:

  • shred and mix fresh organic matter into the soil

  • decompose waxes and lignins

  • feed on bacteria and fungi

Erklärung

Frage 32 von 106

1

The organic matter content of a loam soil declined from 5% to 2% as a result of continued cultivation/tillage. This will result in:

Wähle eine der folgenden:

  • deterioration of soil structure

  • deterioration of soil texture

  • stabilization of soil structure

  • increase in crop yield

Erklärung

Frage 33 von 106

1

The majority of nutrient release occurs during the decomposition of:

Wähle eine der folgenden:

  • humus

  • the slow pool of organic matter

  • the active pool of organic matter

  • the passive pool of organic matter

Erklärung

Frage 34 von 106

1

The pool of organic matter most impacted by organic matter additions in agriculture is:

Wähle eine der folgenden:

  • humus

  • the slow pool

  • the active pool

  • the passive pool

Erklärung

Frage 35 von 106

1

Wähle von der Aufklappliste, um den Text zu vervollständigen.

The "active" pool usually makes up less than ( 10, 1, 0.1, 0.01 ) percent of the total organic matter in a soil.

Erklärung

Frage 36 von 106

1

Which of the following are characteristics of the majority of microorganisms involved in soil organic matter decomposition?

Wähle eine der folgenden:

  • they get C from CO₂ and energy from oxidation of organic compounds

  • they get C and energy from oxidation of organic compounds

  • they get C from CO₂ and energy from oxidation of inorganic compounds

  • none of the above

Erklärung

Frage 37 von 106

1

The basic unit of soil classification is the:

Wähle eine der folgenden:

  • order

  • great group

  • family

  • series

Erklärung

Frage 38 von 106

1

Criteria for grouping soils into orders include:

Wähle eine der folgenden:

  • soil forming processes as indicated by the presence or absence of major diagnostic horizons

  • the thickness of major diagnostic horizons

  • soil temperature, mineralogy, and particle size

  • the specific location of the soil

Erklärung

Frage 39 von 106

1

The highest level of soil classification is the family.

Wähle eins der folgenden:

  • WAHR
  • FALSCH

Erklärung

Frage 40 von 106

1

The soil moisture regime that is used in regions where there are cool, moist winters and long, dry summers with drought is called:

Wähle eine der folgenden:

  • udic

  • xeric

  • aridic

  • ustic

  • aquic

Erklärung

Frage 41 von 106

1

The warmest soil temperature regime is called:

Wähle eine der folgenden:

  • thermic

  • frigid

  • mesic

  • cryic

Erklärung

Frage 42 von 106

1

The Los Osos soil is classified as an Argixeroll. To what soil Order does it belong?

Wähle eine der folgenden:

  • Mollisol

  • Vertisol

  • Gelisol

  • Spodosol

  • Alfisol

Erklärung

Frage 43 von 106

1

This soil order commonly forms out of serpentenite parent material and is characterized as having an abundance of smectite clay. It is not good for building on as it swells during wet periods and shrinks during dry periods.

Wähle eine der folgenden:

  • Mollisol

  • Aridisol

  • Alfisol

  • Ultisol

  • Vertisol

Erklärung

Frage 44 von 106

1

The State Soil of California, San Joaquin, is classified as a Durixeralf. To what soil Order does it belong?

Wähle eine der folgenden:

  • Mollisol

  • Vertisol

  • Gelisol

  • Spodosol

  • Alfisol

Erklärung

Frage 45 von 106

1

Supposing you want to grow corn, soils of which soil order would be best, based on natural fertility?

Wähle eine der folgenden:

  • Mollisol

  • Alfisol

  • Aridisol

  • Entisol

  • Ultisol

Erklärung

Frage 46 von 106

1

Which soil order is commonly found on steep backslope landscape positions or in soils where little or no weathering has taken place?

Wähle eine der folgenden:

  • Ultisol

  • Entisol

  • Andisol

  • Alfisol

  • Aridisol

Erklärung

Frage 47 von 106

1

Soils in this order are commonly sandy in texture, quite acidic and develop primarily under coniferous trees in cool to cold climates:

Wähle eine der folgenden:

  • Mollisols

  • Andisols

  • Spodosols

  • Alifisols

  • Ultisols

Erklärung

Frage 48 von 106

1

A soil on the dry slopes of the Northern Cascades of California is classified as an Xerept. To what soil Order does it belong?

Wähle eine der folgenden:

  • Inceptisol

  • Alfisol

  • Mollisol

  • Ultisol

  • Oxisol

Erklärung

Frage 49 von 106

1

Permafrost is:

Wähle eine der folgenden:

  • material that remains below 0 degrees Celsius for more than two consecutive years

  • is permanently frozen

  • a surface horizon developed by frost heaving

  • is found in soils in the Order Histosols

  • none of the above

Erklärung

Frage 50 von 106

1

Aridisols often contain which of the following horizons?

Wähle eine der folgenden:

  • mollic

  • histic

  • albic

  • calcic

  • none of the above

Erklärung

Frage 51 von 106

1

Wähle von der Aufklappliste, um den Text zu vervollständigen.

Vertisols develop from parent materials rich in ( K, Ca and Mg, Na, Na and K )

Erklärung

Frage 52 von 106

1

Which soil order, containing highly weathered soils composed mainly or iron and aluminum oxide clay, is found in the humid tropics?

Wähle eine der folgenden:

  • Histosol

  • Vertisol

  • Ultisol

  • Oxisol

  • none of the above

Erklärung

Frage 53 von 106

1

Soils that are commonly sandy in texture, quite acidic and develop primarily under coniferous trees in cool to cold climates often contain which of the following horizons?

Wähle eine der folgenden:

  • permafrost

  • argillic

  • albic

  • mollic

  • oxic

Erklärung

Frage 54 von 106

1

Wähle von der Aufklappliste, um den Text zu vervollständigen.

The most dominant soil forming factor for an Aridisol soil would be ( climate, parent material, time, topography, vegetation )

Erklärung

Frage 55 von 106

1

Characteristics of kaolinite clays include:

Wähle eine der folgenden:

  • made up of Fe or Al and O, very little net negative charge, positive charge at low pH, low plasticity, stickiness, and water holding

  • significant substitution in the octahedral, layers weakly held together by cations (highly expansible), CEC of 80-120 cmolc/kg

  • significant substitution in the tetrahedra, layers tightly bound (moderately expansible), CEC of 100-180 cmolc/kg

  • significant substitution in the tetrahedra, potassium ions hold clay layers together tightly (non-expansible), CEC of 20-40 cmolc/kg

  • limited isomorphous substitution, layers are H-bonded (non-expansible), CEC of 2-5 cmolc/kg

Erklärung

Frage 56 von 106

1

The main cations found on the cation exchange complex at a soil pH between 6 and 7 are:

Wähle eine der folgenden:

  • Ca, Al, H

  • Ca, Mg, K

  • K, Al(OH), Mg

  • Al, H, K

Erklärung

Frage 57 von 106

1

Which of the following will be readily leached from soils because of the properties it has that influence how tightly they are held on the exchange complex of clay?

Wähle eine der folgenden:

  • Al

  • H

  • Ca

  • Na

Erklärung

Frage 58 von 106

1

Two major types of soil colloids are:

Wähle eine der folgenden:

  • crystalline silicate clays and humus

  • basic cations and humus

  • crystalline silicate clays and quartz sands

  • primary minerals and secondary minerals

  • quartz sands and humus

Erklärung

Frage 59 von 106

1

Cation exchange capacity is

Wähle eine der folgenden:

  • the amount of exchangeable negatively charged ions per unit weight of dry soil

  • the amount of exchangeable negatively charged and neutral ions per unit weight of soil

  • the amount of exchangeable positively charged ions held per unit weight of dry soil

  • the amount of exchangeable H ions per unit weight of dry soil

Erklärung

Frage 60 von 106

1

Which cation would you expect to find tightly held in a soil at pH 4.5?

Wähle eine der folgenden:

  • K

  • Ca

  • Na

  • Mg

  • Al

Erklärung

Frage 61 von 106

1

The swelling/shrinking tendency of some silicate clay minerals is due primarily to:

Wähle eine der folgenden:

  • the presence of cations attracted by the negative charges on the internal surfaces

  • the movement of water molecules in and out of the interlayers of the crystal

  • varying thickness of the film of water covering the external surface of the particles

  • expansion in the width of the interlayers due to movement of larger ions such as K+

  • the high Mg^2+ contents in the octahedral layers

Erklärung

Frage 62 von 106

1

The accumulation or loss of what compounds result in the formation of hydric soil indicators?

Wähle eine der folgenden:

  • iron, manganese, sulfur, or carbon

  • nitrogen, phosphorus, or potassium

  • iron, carbon, sulfur, or nitrogen

  • iron, manganese, sulfur, or arsenic

Erklärung

Frage 63 von 106

1

Which of the follow is not a characteristic of soil colloids?

Wähle eine der folgenden:

  • very small size

  • high external surfaces

  • electronegativity charges

  • ability to exchange ions with the soil solution

  • low water holding capacity

Erklärung

Frage 64 von 106

1

Wähle von der Aufklappliste, um den Text zu vervollständigen.

The criteria required to define wetlands are wetland hydrology, hydric soils, and ( water standing on the surface, clay subsoils, hydrophytic vegetation )

Erklärung

Frage 65 von 106

1

Wähle von der Aufklappliste, um den Text zu vervollständigen.

Conditions required to form hydric soil indicators are elements that reduce, seasonal or permanent water saturation, microorganisms, and ( water standing on the surface, an organic carbon source, hydrophytic vegetation, clay subsoils )

Erklärung

Frage 66 von 106

1

Wähle von der Aufklappliste, um den Text zu vervollständigen.

The diffusion rate of oxygen in water is 10,000 times ( faster, slower ) than in air.

Erklärung

Frage 67 von 106

1

Possible ecological consequences of poor soil aeration include:

Wähle eine oder mehr der folgenden:

  • slow organic matter decomposition

  • release of greenhouse gases into the atmosphere

  • reduced plant photosynthesis

Erklärung

Frage 68 von 106

1

A major determinant of the aeration status of soils is:

Wähle eine der folgenden:

  • dominant type of clay present

  • pore size and continuity

  • types of wetland plants present

  • presence or absence of carbonates

Erklärung

Frage 69 von 106

1

Which type of water includes that which is available to plants?

Wähle eine der folgenden:

  • hygroscopic water

  • capillary water

  • gravitational water

  • free water

Erklärung

Frage 70 von 106

1

Water moves through soil to plant roots by:

Wähle eine der folgenden:

  • capillary flow from high to low water potential

  • hygroscopic flow

  • transpiration

  • capillary flow from low to high water potential

  • gravitational flow

Erklärung

Frage 71 von 106

1

Water moves further in finer textured soils because:

Wähle eine der folgenden:

  • the granular structure in fine textured soils allows for stronger attraction between water and particles

  • more space between particles causes the bonds of cohesion between water molecules to be stronger

  • there is less space between the particles and the water film is unbroken for longer distances

  • more water is lost by plant transpiration in fine textured soils

Erklärung

Frage 72 von 106

1

The bulk of gaseous interchange in soils takes place by:

Wähle eine der folgenden:

  • mass flow

  • differences in the pressure of N gas

  • diffusion of individual gases along their concentration gradients

  • moving as dissolved ions in soil water

  • aerobic respiration

Erklärung

Frage 73 von 106

1

Clay soils hold more water but have less PAW than loamy soils because:

Wähle eine der folgenden:

  • there is less gravitational water in clay

  • plant roots cannot grow as well in clay soils

  • more hygroscopic water is held on clay particles

  • loamy soils have smaller pores

Erklärung

Frage 74 von 106

1

Sandy soils have less PAW than loamy soils because:

Wähle eine der folgenden:

  • there is less gravitational water in sandy soil

  • plant roots grow better in sandy soils so they use the water faster

  • more hygroscopic water is held on sand particles

  • sandy soils have less surface area

Erklärung

Frage 75 von 106

1

Which type of water is not "held" in soils?

Wähle eine der folgenden:

  • hygroscopic

  • gravitational

  • capillary

  • water of cohesion

Erklärung

Frage 76 von 106

1

Capillarity in soils:

Wähle eine der folgenden:

  • involves both adhesion and cohesion

  • is enhanced by the symmetrical nature of the water molecule

  • is independent of the matric potential in soils

  • does not account for unsaturated water movement in soils

Erklärung

Frage 77 von 106

1

Which type of bond controls retention and movement of water in soils?

Wähle eine der folgenden:

  • capillary

  • covalent

  • pH-dependent

  • hydrogen

Erklärung

Frage 78 von 106

1

PAW is highest in soils with the following texture:

Wähle eine der folgenden:

  • sand

  • sandy loam

  • silty clay loam

  • clay

Erklärung

Frage 79 von 106

1

The electronegative charge on 2:1 type silicate clays is due primarily to:

Wähle eine der folgenden:

  • ionization of surface OH groups

  • substitution of one metallic atom for another in the crystal structure

  • extremely small size of the individual colloid particles

  • the effect of pH on the presence of H+ ions in the exchange complex

  • the preponderance of tetrahedron sheets compared to octahedron sheets

Erklärung

Frage 80 von 106

1

Formation of granular aggregates is aided by:

Wähle eine oder mehr der folgenden:

  • fungal hyphae

  • fine roots

  • microbial and plant exudates

Erklärung

Frage 81 von 106

1

Soils developed from accumulated organic material have which of the following characteristics?

Wähle eine der folgenden:

  • flat, high in clay, and fertile

  • coarse, stony, with fast drainage

  • light, porous, and productive

  • clayey and poorly drained

Erklärung

Frage 82 von 106

1

Secondary minerals are not found in:

Wähle eine der folgenden:

  • metamorphic and sedimentary rocks

  • soils and lacustrine sediments

  • soils and sedimentary rocks

  • igneous rocks and the atmosphere

  • soils and metamorphic rocks

Erklärung

Frage 83 von 106

1

Compared to silt, clay-sized particles are characterized by:

Wähle eine der folgenden:

  • greater attraction for water

  • greater proportion of primarily minerals

  • less attraction for water

  • less capacity to hold nutrients in plant-available forms

Erklärung

Frage 84 von 106

1

Fine sand and smaller particles move parallel to the ground and upward by:

Wähle eine der folgenden:

  • Creep

  • Flow

  • Suspension

  • Turbulence

  • Saltation

Erklärung

Frage 85 von 106

1

Which of the following would NOT reduce water erosion by controlling soil detachment?

Wähle eine der folgenden:

  • barriers

  • stubble mulching

  • conservation tillage

  • cover crops

  • no-till farming practices

Erklärung

Frage 86 von 106

1

Causes of soil erosion include:

Wähle eine oder mehr der folgenden:

  • over-harvesting timberland

  • overgrazing rangeland

  • fire

  • poor farming practices

Erklärung

Frage 87 von 106

1

Wähle von der Aufklappliste, um den Text zu vervollständigen.

Terracing is a means of reducing ( soil transport by wind, soil detachment, soil transport by water, soil saltation in wind )

Erklärung

Frage 88 von 106

1

Wähle von der Aufklappliste, um den Text zu vervollständigen.

When water concentrates in small channels as it runs from the soil surface, it is called ( gully, wind, rill, sheet ) erosion.

Erklärung

Frage 89 von 106

1

The majority of soil particle movement during wind erosion occurs as:

Wähle eine der folgenden:

  • Creep

  • Flow

  • Suspension

  • Turbulence

  • Saltation

Erklärung

Frage 90 von 106

1

Wähle von der Aufklappliste, um den Text zu vervollständigen.

The total global soil lost through erosion is generally greater from ( gully, rill, sheet, wind ) erosion.

Erklärung

Frage 91 von 106

1

Land degradation includes which of the following effects on soil?

Wähle eine oder mehr der folgenden:

  • decline in soil structure

  • reduced microbial biomass

  • salinization

Erklärung

Frage 92 von 106

1

Sulfuric acid can be used instead of gypsum to reclaim sodic soils that contain:

Wähle eine der folgenden:

  • a high buffering capacity

  • free NaCO₃

  • free CaCO₃

  • a high CEC

Erklärung

Frage 93 von 106

1

The exchangeable sodium percentage (ESP):

Wähle eine der folgenden:

  • predicts soil pH by indicating the amount of sodium there is in the soil in relation to the H ions on the exchange complex

  • predicts soil CEC by calculating the amount of sodium there is on the exchange complex

  • expresses the ratio of sodium to aluminum in the octahedral sheet of 2:1 clays

  • indicates the hazard of sodium-induced soil dispersion

Erklärung

Frage 94 von 106

1

Under what precipitation-to-ET conditions would the most severe soil salinization develop?

Wähle eine der folgenden:

  • Ratio of 0.25

  • Ratio of 0.75

  • Ratio of 1.25

  • Ratio of 2.25

Erklärung

Frage 95 von 106

1

Your soil begins to disperse and crop yields decline several years after you start irrigating your garden plot. Which of the following would most likely account for this situation?

Wähle eine der folgenden:

  • high content of Ca and Mg in the irrigation water

  • high content of Na in the irrigation water

  • excessive drainage of the soil

  • high gypsum content in the soil

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Frage 96 von 106

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Sodic soils generally have a poor physical condition. This is most likely due to:

Wähle eine der folgenden:

  • low OM content

  • dispersal of the Na saturated soil colloids

  • impact of raindrops on the soil surface

  • precipitation of the Ca and Mg ions as carbonates

  • high content of smectite in the soils

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Frage 97 von 106

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Techniques for managing saline soils include:

Wähle eine oder mehr der folgenden:

  • keeping the plant root zone wet during sensitive crop stages

  • adding CaCO₃ to replace the Na on the exchange complex

  • applying excess water to increase leaching

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Frage 98 von 106

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Overliming:

Wähle eine oder mehr der folgenden:

  • may occur on coarse-textured soils with low OM

  • may result in NH₃ volatilization if NH₄ is present

  • may result in Fe, Mn, Cu, Zn, P, and B deficiencies

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Frage 99 von 106

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The major role of potassium in plants is:

Wähle eine der folgenden:

  • as part of the chlorophyll molecule

  • regulating cellular respiration

  • energy storage

  • regulating the opening and closing of stomates

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Frage 100 von 106

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Wähle von der Aufklappliste, um den Text zu vervollständigen.

Organic forms of P make up about ( 98%, 50%, 25%, 1% ) of total P in the soil.

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Frage 101 von 106

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Wähle von der Aufklappliste, um den Text zu vervollständigen.

Available forms of potassium in the soil usually make up about ( 95-98%, 25-50%, 10%, 0.1-2% ) of total potassium.

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Frage 102 von 106

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The process of ( nitrification, denitrification, symbiosis, volatilization, mineralization ) releases soluble nitrogen as the result of the breakdown of nitrogen-rich organic compounds.

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Frage 103 von 106

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( Nitrification, Denitrification, Volatilization, Mineralization ) is the process of reduction of NO₃₋ to nitrogen gas by microorganisms under ( aerobic, anaerobic, acidic, alkaline ) soil conditions.

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Frage 104 von 106

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A pH in the range of ( 3.5-4.5, 4.5-5.5, 5.5-7.0, 7.0-8.0, >8.0 ) is when phosphorus is most available to plants.

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Frage 105 von 106

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The highly mobile form of N, which is the main source of N for plants, is:

Wähle eine der folgenden:

  • NH₃

  • NH₄

  • NO₃

  • N₂

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Frage 106 von 106

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The nutrient most limiting for growing food crops in the world is ( phosphorus, carbon, nitrogen, potassium ).

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