The document contains 100 multiple choice questions related to soil science. Some key topics covered include soil classification, soil properties, soil texture, soil structure, soil water, soil aeration, soil biology, soil fertility, and plant nutrition. The questions assess understanding of fundamental concepts and terminology in soil science.

1. 88. The smallestvolumethat can be called a soil.
a. pedon b. horizon c. profile d. aggregate
89. The central component of terrestrial ecosystems
a. flora b. soil c. fauna d. man
90. The horizon sequence representing young soils
a. A-B b. A-C c. A-B-C d. A-E-B-C
91. Materials deposited by ice aretermed
a. eolian b. lacustrine c. colluvial d. till
92. A sequence of soilshavingsimilar factor of information except time and age
a. lithosequence b. chronosequence
c. biosequence d. toposequence
93. It refers to the finest pyroclastic material
a. lapilli b. blocks c. ash d. silt
94. The horizon with the maximum leachingof constituents
a. A horizon b. B horizon c. C horizon d E horizon
95. The type of soil erosion in which soil isuniformly removed
a. sheet erosion b. gully erosion c. rill erosion d. surfaceerosion
96.It indicates thelightness or darkness of soil color
a. hue b. value c. chroma d. all of the above
97. It indicates thepurity or intensity of soil color
a. hue b. value c. chroma d. none of the above
98. Rocks that were formed from the weathering of exposed rocks atthe surfaceof the earth
a. sedimentary rocks b. metamorphic rocks
c. igneous rocks d. volcanic rocks
99. At low moisture content in e soil,soil moisturetension is
a. low b. high c. no relation d. none of the above
100. It refers to the unsaturated zone above the water table
a. groundwater zone b. vadose zone
c. capillary fringezone d. none of the above
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1. Soil practicewhosesize is less than 1 micron.
a. soil colloids b. sand c. silt d. organic matter
2. It is an amorphous or less crystallineclay structure.
a. allophone b. iron oxide c. kaolinite d. silicate
3. The orderly arrangement of atoms in the clay crystallinestructure.
a. latticestructure b. layered structure c. octahedron d. tetrahedron
4. It belongs to the 1:1 non-expandingtype of silicateclay mineral.
a. illite b. kaolinite c. montmorillonite d. vermiculite
5. The process whereby ions absorbed on the surfaceof soil colloidsare exchanged for ions in
the soil solution.
a. anion exchange b. cation exchange
c.ion exchange d. isomorphous substitution
6. The source of permanent negative chargeof clays.
a. anion exchange b. cation exchange
c. isomorphous substitution d. protonation
7. A 25-gm soil saturated with 5 me Ca2+ has a cation exchange capacity equal to:
a. 5 me/100 gm soil b. 10 me Ca/100gm soil
c. 20 me Ca/100 gm soil d. 25 me Ca/100 gm soil
8. Compute the basesaturation of soil w/ a CEC of 100 me/100gm and whose exchange sites
are occupied by 20 me/100gm of basic cations.
a. 20% b.25% c. 60% d. 80%
9. An element which is an important component of plantcell wall.
a. calcium b. magnesium c. nitrogen d. phosphorous
10. The conversion of ammonium form of nitrogen to nitrate.
a. ammonification b. denitrification c. nitrification
d. volatilization
11. The microorganismresponsiblefor the conversion of nitrite to nitrate.
a. azotobacter b. mycorrhizae c. nitobacter d. nitrosomonas

2. 12. The conversion of organic to inorganic forms of nitrogen.
a. immobilization b. mineralization c. nitrification d. volatilization
13. The element which fixes phosphorous atlow soil pH.
a. Al b. Ca c. Mg d.K
14. The measurableexpression of soil reaction.
a. acid saturation b. CEC c.basesaturation d. pH
15. The pH of a soil containingcalciumcarbonatewill notdrop below.
a. pH 6 b. pH 8 c. pH 7 d. pH 9
16. It is also called as burned lime.
a. CaCo3 b. CaO c. CaMg(CO3)2 d. Ca(OH2)
17. The followingarethe beneficial effects of lime,except:
a. itimproves soil structure b. it decreases hydrogen-ion concentration
c. it increases availability of micronutrients d. it stimulates microbial activities
18. The bacteria which livesymbiotically with the roots of legumes and are ableto fix
atmospheric nitrogen.
a. aspergillus b. mycorrhizae c. penicillium d.rhizobia
19. Identify which of the followingis notpart of the nitrogen cycle.
a. disintegration of minerals containingN b. mineralization
c. fixation of rhizobia and other organisms d. plantuptake
20. The most common biological testto evaluate soil fertility.
a. field fertilizer experiment b. use of deficiency symptoms
c. plantanalysis d. soil chemical analysis
21. The oldest ammoniacal sourceof nitrogen fertilizer.
a. Ammonium nitrate b. Ammonium phosphate c. ammonium sulfate d. urea
22. The guaranteed minimum amount of nutrients in a fertilizer material is referred to as:
a. Fertilizer formula b. fertilizer grade
c. fertilizer mixture d. fertilizer recommendation
23. The recommendation is to apply 90 kg N/hectare. This can be satisfied by applyingchicken
dung (2.5%N) at the rate of:
a. 360 kg/hectare b. 2250kg/hectare
c. 3000kg/hectare d. 3600kg/hectare
75. The formula of particledensity
a. Dp=Ms/Vs b. Dp=Ms/Mt c. Dp=Vs/Vt d. Dp=Vt/Ms
76. The porosity of a soil with a bulk density of 1.3 g/cc and a particledensity of 2.6 g/cc.
a. 40% b. 60% c. 50% d. 55%
77. The attraction of water for soil particles
a. cohesion b. adhesion c. surfacetension d. capillarity
78. The force resultingfrom the attraction of soil solids
a. matric force b. osmotic force c. gravitational force d. cohesion force
79. The amount of water remainingin the soil 2 to 3 days after saturation
a. maximum retentive capacity b. permanent wiltingcapacity
c. field capacity d. hydroscopic capacity
80. The matric potential in the soil atsaturation point
a. 0 bar b. 1 bar c. 1/3 bar d. 15 bars
81. The drivingforceof water flow under saturated condition
a. tension gradient b. hydraulic gradient
c. hydraulic conductivity d. gravity
82. The downward entry of water into the soil
a. percolation b. infiltration c. seepage d. hysteresis
83. If the moisture contents of the soil atfield capacity and permanent wiltingpointare40%
and 25%. The availablewater is
a. 10% b. 15% c. 20% d. 30%
84. It is higher in the atmospheric air than the soil air
a. nitrogen b. carbon dioxide c. oxygen d. moisture
85. It accumulates in soil airdueto aerobic decomposition
a. nitrogen b. oxygen c. carbon dioxide d. methane
86. The dominant spectral color in theMunsell color chart.
a. hue b. chroma c. value d. mottles
87. Darked-colored soils
a. absorb more solar radiation b. reflect more solar radiation
c. retains more solar radiation d. none of the above

3. 61. These are soilsformed from volcanic ash and youngvolcanic materials
a. Udepts b. Fluvents c. Udands d. Ustalfs
62. The name Typic Tropudults is for the category of
a. order b. great group c. subgroup d. suborder
63. A group of soilshavingthesame profilecharacteristicsand parentmaterials
a. soil type b. soil series c. soil associationd. soil phase
64. A type of soil survey which produces maps with a scaleof 1:15,000 to 1:5,000.
a. exploratory b. reconnaissance c. semi-detailed d. detailed
65. Maahas clay isan exampleof a
a. soil type b. soil series c. soil association d. soil phase
66. The firststep of soil erosion by water
a. detachment b. transportation c. deposition d. rainfall impact
67. In the USLE equation, the soil cover and management factor is represented by
a. R b. K c. P d. C
68. It is not a master horizon
a. O b. A c. B d. R
69. A type of B horizon showingsignificantclay accumulation
a. Bw b. Bt c. Bk d. Bc
70. The relativeproportion of soil separates
a. soil structure b. soil consistence c. soil texture d. soil aggregation
71. The sizerange of sand
a. 2-0.002 mm b. 2-0.02 mm c. 2-0.2 mm d. 0.02 – 0.002 mm
72. It is the chemical dispersingagentduringtextural analysis
a. sodiumphosphate b. sodiumhexametaphosphate
c. calciumphosphate d. calciumchloride
73. A method of textural analysis
a. hydrometer method b. core c. pycnometer method
d. double ringmethod
74. A basic cation which inhances aggregation
a. Ca b. Na c. K d. Mg
24. A method of fertilizers application whereby fertilizers areapplied uniformly on the soil
surface,
a. banding b. broadcasting c. foliar d. localized placement
25. A method of fertilizer application mostly adapted for orchard an ornamental tree.
a. foliar b. mudball c. seed pelleting d. trench or perforation
26. One of these groups of organisms is notinvolved in the process of ammonification.
a.actinomycetes b. algae c. bacteria d. fungi
27. This is not one of the requirements for the process of nitrification.
a. aerobic condition b. ammonium ions c. nitrate ions d. organisms
28. A method of broadcastingfertilizer materialsover a standingcrop.
a. banding b. basal c. sidedressing d. topdressing
29. Under upland condition,this is themost preferred sourceof N because it leaves less
acidity.
a. ammonium nitrate b. ammonium sulfate
c. ammonium nitrate d. urea
30. The mineral which is the only important natural sourceof phosphorous.
A. apatite b. guano c. feldspar d. mica
31. A method of broadcastingfertilizes whereby the materials areincorporated into the soil
before plantingthe crop.
a. banding b. basal c. sidedressing d. topdressing
32. The level of nutrient in the soil when plants experience luxury consumption.
a. deficient b. excessive c. sufficient d. toxic
33. It states that the yield of the plantis regulated by the nutrient present in the lowest
amount relativeto its optimum requirement.
a. Mineral theory b. Humus theory
c. Law of minimum d. Stokes law
34. The form of sulfur taken up by plants.
A. H2S B. H2SO4 C. S2 d. SO4
35. The pH of the soil atwhich the soil colloidsposses no net charge.
a. neutrality b. alkaline c. acidic d. zero point at change

4. 36. The relativeneutralizingpower of a limingmaterial whosemolecular weight is 84 gm? The
molecular weight of calciumcarbonateis 100 gm.
a. 1.19% b. 84% c. 119% d. 184%
37. The most prominent and numerous soil microorganisms.
a. algae b. actinomycetes c. bacteria d. fungi
38. Soil conditions which can reducethe ferric to ferrous, hence, makingthe iron –phosphate
complex more soluble.
a. continuous tillage b. liming
c. organic matter application d. prolonged anaerobic conditions
39. It is not a function of organic matter in the soil.
a. increases CEC b. provides carbon and energy sourceto soil organisms
c. provideessential elements d. provides soil air
40. The trade name of potassiumchloridefertilizer.
a. ammophos b. muriate of potash c. solophos d.sulfateof potash
41. It belongs to 2:1 silicateminerals.
a. dickite b. halloysite c. kaolinite d. montmorillonite
42. The mineral nutrient needed by the plantin the smallestamount.
a. copper b. molybdenum c. iron d. silicon
43. The most common iron oxidein soil.
a. gibbsite b. hematite c. goethite d. lepidocrocite
44. It is a soil chemical condition thatis common in dry regions.
a. soil acidity b. soil alkalinity c. soil salinity d. all of the above
45. A dynamic natural body composed of mineral and organic materials.
a. clay b. humus c. sediments d. soil
46. The percentage of mineral matter in the soil.
a. 5% b. 25% c. 45% d. 35%
47. The sand fraction is composed mainly of
a. secondary minerals b. primary minerals
c. mineral matter d. organic matter
48. Organic matter decomposition is an example of
a. transformation b. translocation c. addition d. losses
49. The removal of materials in solution fromthe soil
a. percolation b. eluviations c. leaching d. infiltration
50. The parent material that has been deposited by the gravity.
a. alluvial b. colluvial c. marine d. lacustrine
51. The parent material that has been deposited by the wind.
a. alluvial b. colluvial c. till d. eolian
52. The collectiveterm given to accumulated plantdebris.
a. fibric b. muck c. peat d. humus
53. The physical weatheringprocess involvingthepeeling away of rock layers.
a. hydrolysis b. chelation c. exfoliation d. freezing and thawing
54. The reaction between water and the elements of the rock or mineral
a. hydration b. hydrolysis c. carbonation d. oxidation
55. Horizons havingspecific soil characteristicsthatarethe resultof predogenesis.
a. master horizons b. genetic horizons
c. diagnostic horizons d. transition horizons
56. It is likethe mollic epipedon except that ithas lowbase saturation.
a. umbric b. ochric c. melanic d. histic
57. A highly watered subsurfacehorizon consistingof an accumulation of Fe and Al oxides.
a. argillic b. spodic c. cambic d. oxic
58. A hardpan strongly cemented by silica.
a. duripan b. calcic c. fragipan d. gypsic
59. The soil temperature regime when the average annual temperature is more than 220 C
and the difference between mean summer and mean winter is less than 50C.
a. isothermic b. isohyperthermic c. isomesic d. isofrigid
60. These are soilswith littleor no profiledevelopment
a. Udepts b. Fluvents c. Udands d. Ustalfs